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Final assessment of radioactive impurities in the JUNO detector
Authors:
Thomas Adam,
Fengpeng An,
Costas Andreopoulos,
Giuseppe Andronico,
Nikolay Anfimov,
Vito Antonelli,
Tatiana Antoshkina,
João Pedro Athayde Marcondes de André,
Didier Auguste,
Nikita Balashov,
Andrea Barresi,
Davide Basilico,
Eric Baussan,
Marco Beretta,
Antonio Bergnoli,
Nikita Bessonov,
Daniel Bick,
Lukas Bieger,
Svetlana Biktemerova,
Thilo Birkenfeld,
Simon Blyth,
Manuel Böhles,
Anastasia Bolshakova,
Mathieu Bongrand,
Matteo Borghesi
, et al. (549 additional authors not shown)
Abstract:
The Jiangmen Underground Neutrino Observatory (JUNO) collaboration has completed the construction of the 20,000-ton liquid scintillator detector and the associated muon veto detector system. To meet the physics objectives, the materials used in the detector must exhibit low radioactive contamination. The single-event rate in the fiducial volume (R $<$ 17.2 m) of the scintillator is required to be…
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The Jiangmen Underground Neutrino Observatory (JUNO) collaboration has completed the construction of the 20,000-ton liquid scintillator detector and the associated muon veto detector system. To meet the physics objectives, the materials used in the detector must exhibit low radioactive contamination. The single-event rate in the fiducial volume (R $<$ 17.2 m) of the scintillator is required to be approximately 7 Hz for energies above 0.7 MeV, resulting in an accidental coincidence background of about 1 event per day for reactor neutrino physics analyses. Since the beginning of the construction phase, we have screened the natural radioactivity content of thousands of materials, to select those that meet the design background budget. The radioactive impurity concentrations of the materials ultimately used in the JUNO detector are summarized in this paper. The construction of the entire detector and the subsequent filling of the liquid scintillator were completed in August 2025. From the initial data, the total count rate of natural radioactivity within the detector's fiducial volume has met the requirements and is sufficient to support the reactor antineutrino analysis.
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Submitted 19 July, 2026;
originally announced July 2026.
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Operation and performance of ProtoDUNE Dual Phase liquid argon time projection chamber
Authors:
DUNE Collaboration,
S. Abbaslu,
F. Abd Alrahman,
A. Abed Abud,
R. Acciarri,
L. P. Accorsi,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
K. Adhikari,
C. Adriano,
K. Agudelo-Jaramillo,
F. Akbar,
F. Alemanno,
N. S. Alex,
L. Aliaga Soplin,
A. Alqaisi,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
A. Aman,
H. Amar,
R. Amarinei
, et al. (1341 additional authors not shown)
Abstract:
ProtoDUNE-DP was the largest ever built Liquid Argon Time Projection Chamber (LArTPC) operating in Dual-Phase (DP) mode, with a liquid target and charge read-out placed in the gas. It had an active volume of $6\times6\times6$\,m$^3$ corresponding to an active mass of 300\,t (total LAr mass of 720\,t), constructed at the CERN Neutrino Platform and took data from 2019 to 2020 with cosmic muons. In P…
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ProtoDUNE-DP was the largest ever built Liquid Argon Time Projection Chamber (LArTPC) operating in Dual-Phase (DP) mode, with a liquid target and charge read-out placed in the gas. It had an active volume of $6\times6\times6$\,m$^3$ corresponding to an active mass of 300\,t (total LAr mass of 720\,t), constructed at the CERN Neutrino Platform and took data from 2019 to 2020 with cosmic muons. In ProtoDUNE-DP the electric drift field is oriented in the vertical direction, causing the electrons to drift vertically towards the anode at the top. The ionization charge is then extracted into the gaseous argon above the liquid surface, amplified by Townsend avalanches, and collected by the charge readout planes. The detector experienced significant technical problems affecting the long-term operation of the Charge Readout Planes, formed by the Large Electron Multipliers, but other critical segments demonstrated required performance including the delivery of -300 kV to the TPC cathode, verification of replaceable charge read-out electronics, and operation of the photon detection system. ProtoDUNE-DP experience resulted in improved designs of the Vertical Drift LArTPC.
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Submitted 21 July, 2026; v1 submitted 17 July, 2026;
originally announced July 2026.
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Reassessment of Ionospheric Responses to GRB~221009A: Disentangling Instrumental, Illumination and Geophysical Effects
Authors:
Maosheng He,
Quanhan Li,
Shun-Rong Zhang,
Jeffrey M. Forbes,
Jiuhou Lei,
Libo Liu,
Jiankui Shi,
Chi Wang
Abstract:
Gamma-ray bursts (GRBs) have long been proposed to perturb Earth's ionosphere, with occasional reports of disruptions in ultra- and extremely-low-frequency radio signals. The exceptionally bright GRB~221009A was recently claimed to induce multi-altitude ionospheric responses, including perturbations in satellite electric fields, regional total electron content (TEC), and the equatorial electrojet…
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Gamma-ray bursts (GRBs) have long been proposed to perturb Earth's ionosphere, with occasional reports of disruptions in ultra- and extremely-low-frequency radio signals. The exceptionally bright GRB~221009A was recently claimed to induce multi-altitude ionospheric responses, including perturbations in satellite electric fields, regional total electron content (TEC), and the equatorial electrojet (EEJ). These claims have renewed interest in the potential near-Earth impacts of astrophysical transients. Here we perform an independent reassessment using expanded datasets spanning multiple altitudes. We find no coherent, burst-like TEC enhancement, show that the reported electric-field anomalies recur under specific illumination conditions each orbit, and demonstrate that the EEJ fluctuations preceded the burst and coincide with solar-wind variability. Together, these results indicate that the reported GRB-induced ionospheric responses are fully attributable to other natural geophysical processes and instrumental artefacts, thereby resolving a high-profile controversy and clarifying the true limits of GRBs'ionospheric effects.
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Submitted 19 May, 2026;
originally announced May 2026.
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Lattice-Spring Analogy for Isotropic Elasticity
Authors:
D. M. LI,
Meng-Cheng HE
Abstract:
This study introduces an innovative Isotropic Elastic Lattice Spring Model (IELSM) that addresses the fundamental limitation of classical lattice spring models: the constraint of fixed Poisson's ratio. By amending the total strain energy within the Lattice Spring Model (LSM), IELSM provides a self-consistent formulation for simulating isotropic elastic materials with arbitrary Poisson's ratios. Th…
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This study introduces an innovative Isotropic Elastic Lattice Spring Model (IELSM) that addresses the fundamental limitation of classical lattice spring models: the constraint of fixed Poisson's ratio. By amending the total strain energy within the Lattice Spring Model (LSM), IELSM provides a self-consistent formulation for simulating isotropic elastic materials with arbitrary Poisson's ratios. The model's core innovation lies in augmenting classical axial spring frameworks with additional volumetric constraints, establishing a direct and exact mapping between IELSM's parameters and macroscopic elastic constants. This enables simulation across the full admissible Poisson's ratio: -1 < ν < 1 under plane stress and -1 < ν< 0.5 under plane strain conditions. Eigenvalue analysis indicates that the IELSM has better numerical stability compared to the standard bilinear quadrilateral element and the constant strain triangular element. The characteristic of the numerical implementation lies in directly decomposing the additional volumetric constraints into an equivalent combination of standard mechanical components (axial, shear and rotational springs), laying the foundation for the realization of fracture simulation based on discrete methods. Comprehensive validation through uniaxial tension, pure shear, stress concentration around a circular hole, and stress singularity analyses for central and crucifix-shaped cracks demonstrates IELSM's exceptional accuracy, convergence and computational robustness. The model exhibits excellent performance in stress intensity factor calculations at crack tips, validating its effectiveness for singular stress field analysis. This work bridges the gap between LSM and continuum mechanics, establishing an analog framework that maintains theoretical consistency while offering computational accuracy for the solution of elastic boundary value problems.
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Submitted 3 May, 2026;
originally announced May 2026.
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Embedded underwater front-end electronics for the 3-inch photomultipliers in the JUNO experiment
Authors:
Cédric Cerna,
Miao He,
Xiaoshan Jiang,
Juan Pedro Ochoa-Ricoux,
Frédéric Perrot,
Angel Abusleme,
Thomas Adam,
Fengpeng An,
Costas Andreopoulos,
Giuseppe Andronico,
João Pedro Athayde Marcondes de André,
Nikolay Anfimov,
Vito Antonelli,
Tatiana Antoshkina,
Didier Auguste,
Nikita Balashov,
Andrea Barresi,
Davide Basilico,
Eric Baussan,
Marco Beretta,
Antonio Bergnoli,
Nikita Bessonov,
Daniel Bick,
Lukas Bieger,
Svetlana Biktemerova
, et al. (576 additional authors not shown)
Abstract:
The Jiangmen Underground Neutrino Observatory (JUNO) is a 20-kton liquid scintillator-based, low-radioactivity, multi-purpose neutrino detector located 693 meters (1800 m.w.e.) underground in the Guangdong province, China. To detect scintillation light produced in the target, the detector is equipped with 17,612 20-inch photomultipliers (PMTs), forming the Large PMT system (LPMT). In addition, 25,…
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The Jiangmen Underground Neutrino Observatory (JUNO) is a 20-kton liquid scintillator-based, low-radioactivity, multi-purpose neutrino detector located 693 meters (1800 m.w.e.) underground in the Guangdong province, China. To detect scintillation light produced in the target, the detector is equipped with 17,612 20-inch photomultipliers (PMTs), forming the Large PMT system (LPMT). In addition, 25,600 3-inch photomultipliers (the Small Photomultiplier System or SPMT) are deployed in the gaps between the LPMTs.
This paper presents the design and performance of the underwater front-end electronics developed for the SPMT system. It details the individual electronics boards and their key components, the inter-board interfaces, the system-level design, and the firmware architecture that supports data acquisition and control. It also outlines mechanical and thermal integration, board validation procedures, and system performance metrics. The readout chain includes digitization of 128 PMT channels per unit, synchronized time-stamping, charge measurement, event packaging, and bandwidth management. Comprehensive validation confirms the system's readiness to meet JUNO's stringent physics goals. The underwater electronics achieve noise levels as low as 0.04 photoelectrons with minimal crosstalk (below 0.4%) and a bandwidth of 57 MB/s, ensuring reliable single photo-electron detection and operation under high-rate conditions. The SPMT system has now been fully integrated and installed in JUNO. Its commissioning and physics performance will be reported in a future publication.
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Submitted 1 June, 2026; v1 submitted 28 April, 2026;
originally announced April 2026.
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Wave-number-dependent closure condition for fluid moment equations
Authors:
Yong Sun,
Shijia Chen,
Minqing He,
Sizhong Wu,
Rui Cheng,
Jie Yang,
Lei Yang,
Zhiyu Sun,
Liangwen Chen,
Hua Zhang
Abstract:
Fluid models offer crucial computational efficiency for plasma simulations, yet accurately capturing kinetic effects like Landau damping remains a fundamental challenge. While conventional closures (e.g., Hammett-Perkins and Hunana) are widely used, their fidelity relative to exact kinetic response degrades significantly depending on the perturbation wave number. Here, we propose a novel wave-numb…
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Fluid models offer crucial computational efficiency for plasma simulations, yet accurately capturing kinetic effects like Landau damping remains a fundamental challenge. While conventional closures (e.g., Hammett-Perkins and Hunana) are widely used, their fidelity relative to exact kinetic response degrades significantly depending on the perturbation wave number. Here, we propose a novel wave-number-dependent closure condition for the three-moment fluid equations that explicitly preserves the primary dispersion relation. By mapping Padé approximant coefficients directly to the kinetic roots of the collisionless Vlasov-Poisson system, we derive an analytical closure that rigorously embeds exact kinetic scaling across all spatial scales. We further demonstrate that this framework readily extends to collisional plasmas via the BGK model. This deterministic approach precisely captures the long-term macroscopic evolution of fluid moments and field energy, offering a rigorous foundation for high-fidelity fluid modeling.
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Submitted 28 April, 2026; v1 submitted 27 April, 2026;
originally announced April 2026.
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Charge readout electronics for the DUNE horizontal drift far detector: design and performance in ProtoDUNE-HD
Authors:
DUNE Collaboration,
S. Abbaslu,
F. Abd Alrahman,
A. Abed Abud,
R. Acciarri,
L. P. Accorsi,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
K. Adhikari,
C. Adriano,
K. Agudelo-Jaramillo,
F. Akbar,
F. Alemanno,
N. S. Alex,
L. Aliaga Soplin,
A. Alqaisi,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
A. Aman,
H. Amar,
R. Amarinei
, et al. (1346 additional authors not shown)
Abstract:
DUNE (Deep Underground Neutrino Experiment) is a long-baseline neutrino oscillation experiment currently under construction, whose far detectors will be the largest liquid argon time projection chambers ever built. This detector design calls for custom-built cryogenic front-end electronics to meet its performance requirements. This paper describes the charge readout electronics that will be used i…
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DUNE (Deep Underground Neutrino Experiment) is a long-baseline neutrino oscillation experiment currently under construction, whose far detectors will be the largest liquid argon time projection chambers ever built. This detector design calls for custom-built cryogenic front-end electronics to meet its performance requirements. This paper describes the charge readout electronics that will be used in the DUNE horizontal drift (HD) far detector and presents performance results using data from the ProtoDUNE-HD detector, a 770 ton liquid argon time projection chamber operated at the CERN Neutrino Platform in 2024 that served as the final prototype of the DUNE HD design.
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Submitted 12 August, 2026; v1 submitted 26 April, 2026;
originally announced April 2026.
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Realistic Detector Geometry Modeling and Its Impact on Event Reconstruction in JUNO
Authors:
Zhaoxiang Wu,
Miao He,
Wuming Luo,
Ziyan Deng,
Wei He,
Yuekun Heng,
Xiaoping Jing,
Bo Li,
Xiaoyan Ma,
Xiaohui Qian,
Zhonghua Qin,
Yifang Wang,
Peidong Yu
Abstract:
JUNO is designed to determine the neutrino mass ordering with an energy resolution of 3% at 1 MeV. In the real detector, however, deformations of the central stainless-steel structure during installation lead to deviations of the photomultiplier tube (PMT) positions from their design values. Based on the limited survey data of the PMTs and the stainless-steel truss, we perform a correlation analys…
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JUNO is designed to determine the neutrino mass ordering with an energy resolution of 3% at 1 MeV. In the real detector, however, deformations of the central stainless-steel structure during installation lead to deviations of the photomultiplier tube (PMT) positions from their design values. Based on the limited survey data of the PMTs and the stainless-steel truss, we perform a correlation analysis of the measured points and propose a method to predict the positions of all PMTs. Using the resulting realistic geometry, we demonstrate that the detector deformation has a negligible effect on the energy reconstruction. In contrast, inaccuracies in the assumed geometry can introduce vertex biases of up to 40 mm. Incorporating the realistic geometry into the calibration-based PMT response model removes this bias and preserves the stability of the reconstruction algorithms.
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Submitted 15 April, 2026;
originally announced April 2026.
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Broadband terahertz comb with sub-Hz comb linewidth
Authors:
Min Li,
Yu Xia,
Yuan Chen,
Sinan Tao,
Mingyang He,
Kun Huang,
Hua Li,
Ming Yan,
Heping Zeng
Abstract:
Terahertz (THz) frequency combs are increasingly essential for spectroscopy, metrology, and quantum science. However, generating a dense array of evenly spaced ultra-narrow THz comb lines is challenging. Here, we demonstrate broadband THz comb generation using a photoconductive antenna that transfers a noise-suppressed near-infrared electro-optical (EO) comb into the THz domain. Our noise-suppress…
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Terahertz (THz) frequency combs are increasingly essential for spectroscopy, metrology, and quantum science. However, generating a dense array of evenly spaced ultra-narrow THz comb lines is challenging. Here, we demonstrate broadband THz comb generation using a photoconductive antenna that transfers a noise-suppressed near-infrared electro-optical (EO) comb into the THz domain. Our noise-suppression strategy, leveraging soliton self-frequency shift and spectral filtering, effectively suppresses EO comb phase noise without requiring active stabilization. The resulting THz comb exhibits broad spectral coverage (0.05-4 THz), narrow comb linewidths (0.3 Hz at the Fourier-transform limit), and excellent frequency stability (8.6*10^-14 at 1-second integration). We further demonstrate asynchronous THz time-domain spectroscopy, resolving ~36,000 comb lines with 50 MHz spacing. Crucially, the inherent frequency agility of the EO comb enables rapid and wide-range tuning of the THz comb line spacing. These attributes position our THz comb as a versatile tool for high-resolution molecular spectroscopy and precision THz metrology.
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Submitted 6 February, 2026;
originally announced February 2026.
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Electrically pumped AlGaN edge-emitting UV-B laser diodes grown by molecular beam epitaxy
Authors:
Huabin Yu,
Shubham Mondal,
Rui Shen,
Md Tanvir Hasan,
David He,
Jiangnan Liu,
Samuel Yang,
Minming He,
Omar Alkhazragi,
Danhao Wang,
Mackillo Kira,
Parag Deotare,
Di Liang,
Zetian Mi
Abstract:
Mid and deep ultraviolet (UV) laser diodes remain among the least explored devices in semiconductor optoelectronics, despite their importance for spectroscopy, biochemical sensing, disinfection, and emerging quantum photonics. Here, we demonstrate an electrically pumped AlGaN-based laser diode operating in the UV-B band (280-315 nm). The device is grown by molecular beam epitaxy (MBE) on single-cr…
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Mid and deep ultraviolet (UV) laser diodes remain among the least explored devices in semiconductor optoelectronics, despite their importance for spectroscopy, biochemical sensing, disinfection, and emerging quantum photonics. Here, we demonstrate an electrically pumped AlGaN-based laser diode operating in the UV-B band (280-315 nm). The device is grown by molecular beam epitaxy (MBE) on single-crystal AlN substrate and fabricated in a ridge-waveguide geometry. The laser diode operates at 298.5 nm and exhibits a relatively low threshold current density of 3.4 kA/cm$^2$. Clear nonlinear light-current characteristics and pronounced spectral narrowing with a full-width-at-half-maximum (FWHM) of 0.2 nm are measured above threshold.
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Submitted 27 January, 2026;
originally announced January 2026.
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Probing Anharmonic Lattice Dynamics and Thermal Transport in Layered Perovskite LiYTiO4 Anode
Authors:
Lin Zhang,
Wen Liu,
Mingquan He,
Jun Huang
Abstract:
Layered perovskite lithium yttrium titanate ($\rm LiYTiO_4$) has recently emerged as a promising low-potential, ultrahigh-rate intercalation-type anode material for lithium-ion batteries; however, its lattice dynamics and thermal transport properties remain poorly understood, limiting a complete evaluation of its practical potential. Here, we combine experimental measurements with theoretical mode…
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Layered perovskite lithium yttrium titanate ($\rm LiYTiO_4$) has recently emerged as a promising low-potential, ultrahigh-rate intercalation-type anode material for lithium-ion batteries; however, its lattice dynamics and thermal transport properties remain poorly understood, limiting a complete evaluation of its practical potential. Here, we combine experimental measurements with theoretical modeling to systematically investigate the anharmonic lattice dynamics and heat transport in $\rm LiYTiO_4$. We employ a neural evolution potential (NEP)-based framework that integrates the temperature-dependent effective potential method with the Wigner thermal transport (WTT) formalism, explicitly including both diagonal and off-diagonal terms of the heat-flux operator. Zero-temperature phonon calculations reveal dynamical instabilities associated with $\rm TiO_6$ octahedral rotation, which are stabilized at finite temperatures through anharmonic renormalization. Using the WTT approach with contributions from phonon propagation and coherence contributions, we predict a room-temperature lattice thermal conductivity ($κ_{\rm L}$) of 3.8 $\rm Wm^{-1}K^{-1}$ averaged over all crystal orientations, in close agreement with the measured value of 3.2 \pm 0.08 $\rm Wm^{-1}K^{-1}$ for polycrystalline samples. To further examine the possible influence of ionic motion on high-temperature thermal transport, we compute $κ_{\rm L}$ using a Green-Kubo equilibrium molecular dynamics approach based on the same NEP, which yields consistent results with both experiment and WTT predictions, confirming the negligible role of Li-ion mobility in heat conduction. Our study not only identifies the ultralow thermal conductivity of $\rm LiYTiO_4$ as a key limitation for its practical application but also establishes a reliable computational framework for studying thermal properties in battery materials.
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Submitted 7 December, 2025;
originally announced December 2025.
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Optical diffraction neural networks assisted computational ghost imaging through dynamic scattering media
Authors:
Yue-Gang Li,
Ze Zheng,
Jun-jie Wang,
Ming He,
Jianping Fan,
Tailong Xiao,
Guihua Zeng
Abstract:
Ghost imaging leverages a single-pixel detector with no spatial resolution to acquire object echo intensity signals, which are correlated with illumination patterns to reconstruct an image. This architecture inherently mitigates scattering interference between the object and the detector but sensitive to scattering between the light source and the object. To address this challenge, we propose an o…
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Ghost imaging leverages a single-pixel detector with no spatial resolution to acquire object echo intensity signals, which are correlated with illumination patterns to reconstruct an image. This architecture inherently mitigates scattering interference between the object and the detector but sensitive to scattering between the light source and the object. To address this challenge, we propose an optical diffraction neural networks (ODNNs) assisted ghost imaging method for imaging through dynamic scattering media. In our scheme, a set of fixed ODNNs, trained on simulated datasets, is incorporated into the experimental optical path to actively correct random distortions induced by dynamic scattering media. Experimental validation using rotating single-layer and double-layer ground glass confirms the feasibility and effectiveness of our approach. Furthermore, our scheme can also be combined with physics-prior-based reconstruction algorithms, enabling high-quality imaging under undersampled conditions. This work demonstrates a novel strategy for imaging through dynamic scattering media, which can be extended to other imaging systems.
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Submitted 28 November, 2025;
originally announced November 2025.
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Initial performance results of the JUNO detector
Authors:
Angel Abusleme,
Thomas Adam,
Kai Adamowicz,
David Adey,
Shakeel Ahmad,
Rizwan Ahmed,
Timo Ahola,
Sebastiano Aiello,
Fengpeng An,
Guangpeng An,
Costas Andreopoulos,
Giuseppe Andronico,
João Pedro Athayde Marcondes de André,
Nikolay Anfimov,
Vito Antonelli,
Tatiana Antoshkina,
Burin Asavapibhop,
Didier Auguste,
Margherita Buizza Avanzini,
Andrej Babic,
Jingzhi Bai,
Weidong Bai,
Nikita Balashov,
Roberto Barbera,
Andrea Barresi
, et al. (1114 additional authors not shown)
Abstract:
The Jiangmen Underground Neutrino Observatory (JUNO) started physics data taking on 26 August 2025. JUNO consists of a 20-kton liquid scintillator central detector, surrounded by a 35 kton water pool serving as a Cherenkov veto, and almost 1000 m$^2$ of plastic scintillator veto on top. The detector is located in a shallow underground laboratory with an overburden of 1800 m.w.e. This paper present…
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The Jiangmen Underground Neutrino Observatory (JUNO) started physics data taking on 26 August 2025. JUNO consists of a 20-kton liquid scintillator central detector, surrounded by a 35 kton water pool serving as a Cherenkov veto, and almost 1000 m$^2$ of plastic scintillator veto on top. The detector is located in a shallow underground laboratory with an overburden of 1800 m.w.e. This paper presents the performance results of the detector, extensively studied during the commissioning of the water phase, the subsequent liquid scintillator filling phase, and the first physics runs. The liquid scintillator achieved an attenuation length of 20.6 m at 430 nm, while the high coverage PMT system and scintillator together yielded about 1785 photoelectrons per MeV of energy deposit at the detector centre, measured using the 2.223 MeV $γ$ from neutron captures on hydrogen with an Am-C calibration source. The reconstructed energy resolution is 3.4% for two 0.511 MeV $γ$ at the detector centre and 2.9% for the 0.93 MeV quenched Po-214 alpha decays from natural radioactive sources. The energy nonlinearity is calibrated to better than 1%. Intrinsic contaminations of U-238 and Th-232 in the liquid scintillator are below 10$^{-16}$ g/g, assuming secular equilibrium. The water Cherenkov detector achieves a muon detection efficiency better than 99.9% for muons traversing the liquid scintillator volume. During the initial science runs, the data acquisition duty cycle exceeded 97.8%, demonstrating the excellent stability and readiness of JUNO for high-precision neutrino physics.
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Submitted 18 November, 2025;
originally announced November 2025.
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Prospects for geoneutrino detection with JUNO
Authors:
Thomas Adam,
Shakeel Ahmad,
Rizwan Ahmed,
Fengpeng An,
João Pedro Athayde Marcondes de André,
Costas Andreopoulos,
Giuseppe Andronico,
Nikolay Anfimov,
Vito Antonelli,
Tatiana Antoshkina,
Didier Auguste,
Marcel Büchner,
Weidong Bai,
Nikita Balashov,
Andrea Barresi,
Davide Basilico,
Eric Baussan,
Marco Beretta,
Antonio Bergnoli,
Nikita Bessonov,
Daniel Bick,
Lukas Bieger,
Svetlana Biktemerova,
Thilo Birkenfeld,
Simon Blyth
, et al. (605 additional authors not shown)
Abstract:
Geoneutrinos, which are antineutrinos emitted during the decay of long-lived radioactive elements inside Earth, serve as a unique tool for studying the composition and heat budget of our planet. The Jiangmen Underground Neutrino Observatory (JUNO) experiment in China, which has recently completed construction, is expected to collect a sample comparable in size to the entire existing world geoneutr…
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Geoneutrinos, which are antineutrinos emitted during the decay of long-lived radioactive elements inside Earth, serve as a unique tool for studying the composition and heat budget of our planet. The Jiangmen Underground Neutrino Observatory (JUNO) experiment in China, which has recently completed construction, is expected to collect a sample comparable in size to the entire existing world geoneutrino dataset in less than a year. This paper presents an updated estimation of sensitivity to geoneutrinos of JUNO using the best knowledge available to date about the experimental site, the surrounding nuclear reactors, the detector response uncertainties, and the constraints expected from the TAO satellite detector. To facilitate comparison with present and future geological models, our results cover a wide range of predicted signal strengths. Despite the significant background from reactor antineutrinos, the experiment will measure the total geoneutrino flux with a precision comparable to that of existing experiments within its first few years, ultimately achieving a world-leading precision of about 8% over ten years. The large statistics of JUNO will also allow separation of the Uranium-238 and Thorium-232 contributions with unprecedented precision, providing crucial constraints on models of formation and composition of Earth. Observation of the mantle signal above the lithospheric flux will be possible but challenging. For models with the highest predicted mantle concentrations of heat-producing elements, a 3-sigma detection over six years requires knowledge of the lithospheric flux to within 15%. Together with complementary measurements from other locations, the geoneutrino results of JUNO will offer cutting-edge, high-precision insights into the interior of Earth, of fundamental importance to both the geoscience and neutrino physics communities.
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Submitted 10 November, 2025;
originally announced November 2025.
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Design, waterproofing, and mass production of the 3-inch PMT frontend system of JUNO
Authors:
Jilei Xu,
Miao He,
Cédric Cerna,
Yongbo Huang,
Thomas Adam,
Shakeel Ahmad,
Rizwan Ahmed,
Fengpeng An,
Costas Andreopoulos,
Giuseppe Andronico,
João Pedro Athayde Marcondes de André,
Nikolay Anfimov,
Vito Antonelli,
Tatiana Antoshkina,
Didier Auguste,
Weidong Bai,
Nikita Balashov,
Andrea Barresi,
Davide Basilico,
Eric Baussan,
Marco Beretta,
Antonio Bergnoli,
Nikita Bessonov,
Daniel Bick,
Lukas Bieger
, et al. (609 additional authors not shown)
Abstract:
Over 25,600 3-inch photomultiplier tubes (PMTs) have been instrumented for the central detector of the Jiangmen Underground Neutrino Observatory. Each PMT is equipped with a high-voltage divider and a frontend cable with waterproof sealing. Groups of sixteen PMTs are connected to the underwater frontend readout electronics via specialized multi-channel waterproof connectors. This paper outlines th…
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Over 25,600 3-inch photomultiplier tubes (PMTs) have been instrumented for the central detector of the Jiangmen Underground Neutrino Observatory. Each PMT is equipped with a high-voltage divider and a frontend cable with waterproof sealing. Groups of sixteen PMTs are connected to the underwater frontend readout electronics via specialized multi-channel waterproof connectors. This paper outlines the design and mass production processes for the high-voltage divider, the cable and connector, as well as the waterproof potting of the PMT bases. The results of the acceptance tests of all the integrated PMTs are also presented.
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Submitted 22 January, 2026; v1 submitted 7 October, 2025;
originally announced October 2025.
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Finite elements and moving asymptotes accelerate quantum optimal control -- FEMMA
Authors:
Mengjia He,
Yongbo Deng,
Burkhard Luy,
Jan G. Korvink
Abstract:
Quantum optimal control is central to designing spin manipulation pulses. Gradient-based pulse optimization can be facilitated by either accelerating gradient evaluation or enhancing the convergence rate. In this work, we accelerated single-spin optimal control by combining the finite element method with the method of moving asymptotes. By treating discretized time as spatial coordinates, the Liou…
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Quantum optimal control is central to designing spin manipulation pulses. Gradient-based pulse optimization can be facilitated by either accelerating gradient evaluation or enhancing the convergence rate. In this work, we accelerated single-spin optimal control by combining the finite element method with the method of moving asymptotes. By treating discretized time as spatial coordinates, the Liouville - von Neumann equation was reformulated as a linear system, efficiently yielding a joint solution of the spin trajectory and control gradient. The method of moving asymptotes, relying on the ensemble fidelities and gradients, achieves rapid convergence for a target fidelity of 0.995.
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Submitted 20 January, 2026; v1 submitted 6 October, 2025;
originally announced October 2025.
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Operation of a Modular 3D-Pixelated Liquid Argon Time-Projection Chamber in a Neutrino Beam
Authors:
DUNE Collaboration,
S. Abbaslu,
A. Abed Abud,
R. Acciarri,
L. P. Accorsi,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
C. Adriano,
F. Akbar,
F. Alemanno,
N. S. Alex,
K. Allison,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
A. Aman,
H. Amar,
P. Amedo,
J. Anderson,
D. A. Andrade,
C. Andreopoulos,
M. Andreotti
, et al. (1299 additional authors not shown)
Abstract:
The 2x2 Demonstrator, a prototype for the Deep Underground Neutrino Experiment (DUNE) liquid argon (LAr) Near Detector, was exposed to the Neutrinos from the Main Injector (NuMI) neutrino beam at Fermi National Accelerator Laboratory (Fermilab). This detector prototypes a new modular design for a liquid argon time-projection chamber (LArTPC), comprised of a two-by-two array of four modules, each f…
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The 2x2 Demonstrator, a prototype for the Deep Underground Neutrino Experiment (DUNE) liquid argon (LAr) Near Detector, was exposed to the Neutrinos from the Main Injector (NuMI) neutrino beam at Fermi National Accelerator Laboratory (Fermilab). This detector prototypes a new modular design for a liquid argon time-projection chamber (LArTPC), comprised of a two-by-two array of four modules, each further segmented into two optically-isolated LArTPCs. The 2x2 Demonstrator features a number of pioneering technologies, including a low-profile resistive field shell to establish drift fields, native 3D ionization pixelated imaging, and a high-coverage dielectric light readout system. The 2.4 tonne active mass detector is flanked upstream and downstream by supplemental solid-scintillator tracking planes, repurposed from the MINERvA experiment, which track ionizing particles exiting the argon volume. The antineutrino beam data collected by the detector over a 4.5 day period in 2024 include over 30,000 neutrino interactions in the LAr active volume-the first neutrino interactions reported by a DUNE detector prototype. During its physics-quality run, the 2x2 Demonstrator operated at a nominal drift field of 500 V/cm and maintained good LAr purity, with a stable electron lifetime of approximately 1.25 ms. This paper describes the detector and supporting systems, summarizes the installation and commissioning, and presents the initial validation of collected NuMI beam and off-beam self-triggers. In addition, it highlights observed interactions in the detector volume, including candidate muon anti-neutrino events.
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Submitted 17 June, 2026; v1 submitted 6 September, 2025;
originally announced September 2025.
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Real-time imaging through dynamic scattering media enabled by fixed optical modulations
Authors:
Yuegang Li,
Junjie Wang,
Tailong Xiao,
Ze Zheng,
Jingzheng Huang,
Ming He,
Jianping Fan,
Guihua Zeng
Abstract:
Dynamic scattering remains a significant challenge to the practical deployment of anti-scattering imaging. Existing methods, such as transmission matrix measurements, iterative wavefront shaping, and optical phase conjugation, depend on a quasi-static assumption, requiring the object and scattering medium to remain stable during a single imaging process to enable one-to-one compensation. However,…
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Dynamic scattering remains a significant challenge to the practical deployment of anti-scattering imaging. Existing methods, such as transmission matrix measurements, iterative wavefront shaping, and optical phase conjugation, depend on a quasi-static assumption, requiring the object and scattering medium to remain stable during a single imaging process to enable one-to-one compensation. However, image reconstruction becomes unattainable when this assumption is violated. Here, we propose a novel imaging strategy that counteracts time-dependent scattering perturbations through a fixed modulation module. This one-to-many compensation mechanism is realized via optical diffraction neural networks (ODNNs) trained on simulated datasets. For the first time, we reveal that its feasibility stems from the optical shower-curtain effect, and its effectiveness typically within 1-2 transport mean free paths. Our approach is not only immune to speckle decorrelation but also leverages it to enhance image quality. ODNNs generalize effectively to real-world scattering medium scenarios via multi-simulated scattering media learning and reconstruct images in real time with light-speed processing. We achieve 80 Hz imaging of moving objects in dynamic scattering media with decorrelation times < 1 ms, demonstrating applicability in large-field-of-view imaging and incoherent illumination scenarios. This work lays the foundation for high-speed, intelligent optical imaging, advancing practical anti-dynamic scattering techniques.
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Submitted 21 August, 2025;
originally announced August 2025.
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Topologically Protected Polaritonic Bound State in the Continuum
Authors:
Harsh Gupta,
Tatiana Contino,
Mingze He,
Eli Janzen,
James H. Edgar,
Andrea Alu,
Michele Tamagnone
Abstract:
Bound states in the continuum (BICs) have emerged as powerful tools to realize ultra-high-Q resonances in nanophotonics. While previous implementations have primarily relied on dielectric metasurfaces, their optical confinement remains fundamentally limited by diffraction. In this work, we theoretically and numerically demonstrate and experimentally validate the existence of topologically protecte…
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Bound states in the continuum (BICs) have emerged as powerful tools to realize ultra-high-Q resonances in nanophotonics. While previous implementations have primarily relied on dielectric metasurfaces, their optical confinement remains fundamentally limited by diffraction. In this work, we theoretically and numerically demonstrate and experimentally validate the existence of topologically protected phonon-polaritonic BICs in periodic arrays of cylindrical nanoresonators composed of isotopically enriched hexagonal boron nitride (h11BN), which support two restrahlen bands (lower (type-I) and upper (type II)), with the present work focusing on the lower Reststrahlen band (RB-1). Owing to the uniaxial anisotropy of hBN and the rotational symmetry of the structure, these systems support topologically symmetry-protected BICs at the Γ-point, where radiative losses are suppressed. The total quality factor is ultimately bounded by the intrinsic phonon damping of h11BN, enabling high-Q polaritonic modes with minimal radiation leakage. When cylindrical symmetry is broken via angular tilting of incident light away from normal incidence, these BICs transition into quasi-BICs (q-BICs), with strong field confinement and tunable radiation leakage. Their topological features enable robust control over mode lifetimes and confinement, paving the way towards scalable polaritonic platforms for mid-infrared optoelectronics, sensing and quantum nanophotonics.
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Submitted 25 May, 2026; v1 submitted 20 August, 2025;
originally announced August 2025.
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Spatial and Temporal Evaluations of the Liquid Argon Purity in ProtoDUNE-SP
Authors:
DUNE Collaboration,
S. Abbaslu,
A. Abed Abud,
R. Acciarri,
L. P. Accorsi,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
C. Adriano,
F. Akbar,
F. Alemanno,
N. S. Alex,
K. Allison,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
A. Aman,
H. Amar,
P. Amedo,
J. Anderson,
D. A. Andrade,
C. Andreopoulos,
M. Andreotti
, et al. (1301 additional authors not shown)
Abstract:
Liquid argon time projection chambers (LArTPCs) rely on highly pure argon to ensure that ionization electrons produced by charged particles reach readout arrays. ProtoDUNE Single-Phase (ProtoDUNE-SP) was an approximately 700-ton liquid argon detector intended to prototype the Deep Underground Neutrino Experiment (DUNE) Far Detector Horizontal Drift module. It contains two drift volumes bisected by…
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Liquid argon time projection chambers (LArTPCs) rely on highly pure argon to ensure that ionization electrons produced by charged particles reach readout arrays. ProtoDUNE Single-Phase (ProtoDUNE-SP) was an approximately 700-ton liquid argon detector intended to prototype the Deep Underground Neutrino Experiment (DUNE) Far Detector Horizontal Drift module. It contains two drift volumes bisected by the cathode plane assembly, which is biased to create an almost uniform electric field in both volumes. The DUNE Far Detector modules must have robust cryogenic systems capable of filtering argon and supplying the TPC with clean liquid. This paper will explore comparisons of the argon purity measured by the purity monitors with those measured using muons in the TPC from October 2018 to November 2018. A new method is introduced to measure the liquid argon purity in the TPC using muons crossing both drift volumes of ProtoDUNE-SP. For extended periods on the timescale of weeks, the drift electron lifetime was measured to be above 30 ms using both systems. A particular focus will be placed on the measured purity of argon as a function of position in the detector.
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Submitted 27 August, 2025; v1 submitted 11 July, 2025;
originally announced July 2025.
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A highly sensitive SF$_6$-based leak test system for JUNO 3-inch PMT underwater electronics boxes
Authors:
Ziliang Chu,
Diru Wu,
Miao He,
Jilei Xu,
Xiaoping Jing,
Jian Wang
Abstract:
A total of 25600 3-inch photomultiplier tubes (PMTs), along with their corresponding frontend electronics, have been installed at the Jiangmen Underground Neutrino Observatory (JUNO). These electronics are housed in 200 stainless steel boxes that operate underwater. To verify the sealing integrity of the underwater boxes following integration, we developed an SF$_6$-based leak test system, opting…
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A total of 25600 3-inch photomultiplier tubes (PMTs), along with their corresponding frontend electronics, have been installed at the Jiangmen Underground Neutrino Observatory (JUNO). These electronics are housed in 200 stainless steel boxes that operate underwater. To verify the sealing integrity of the underwater boxes following integration, we developed an SF$_6$-based leak test system, opting against the typical helium-based system due to helium's ability to penetrate the PMT glass. After a few hours of accumulating leaking SF$_6$ from the underwater boxes, a leak rate detection limit of $2.3\times{10}^{-9}$~Pa$\cdot$m$^3$/s in terms of SF$_6$ was achieved, corresponding to $1.65\times{10}^{-8}$~Pa$\cdot$ m$^3$/s helium equivalent. This meets the sensitivity requirement of 1$\times$10$^{-7}$~Pa$\cdot$m$^3$/s. This system was critical in identifying and replacing a few cases of leaking underwater boxes before installation.
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Submitted 29 May, 2025;
originally announced May 2025.
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Harnessing self-sensitized scintillation by supramolecular engineering of CsPbBr3 nanocrystals in dense mesoporous template nanospheres
Authors:
Xiaohe Zhou,
Matteo L. Zaffalon,
Emanuele Mazzola,
Andrea Fratelli,
Francesco Carulli,
Chenger Wang,
Mengda He,
Francesco Bruni,
Saptarshi Chakraborty,
Leonardo Poletti,
Francesca Rossi,
Luca Gironi,
Francesco Meinardi,
Liang Li,
Sergio Brovelli
Abstract:
Perovskite-based nanoscintillators, such as CsPbBr3 nanocrystals (NCs), are emerging as promising candidates for ionizing radiation detection, thanks to their high emission efficiency, rapid response, and facile synthesis. However, their nanoscale dimensions - smaller than the mean free path of secondary carriers - and relatively low emitter density per unit volume, limited by their high molecular…
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Perovskite-based nanoscintillators, such as CsPbBr3 nanocrystals (NCs), are emerging as promising candidates for ionizing radiation detection, thanks to their high emission efficiency, rapid response, and facile synthesis. However, their nanoscale dimensions - smaller than the mean free path of secondary carriers - and relatively low emitter density per unit volume, limited by their high molecular weight and reabsorption losses, restrict efficient secondary carrier conversion and hamper their practical deployment. In this work, we introduce a strategy to enhance scintillation performance by organizing NCs into densely packed domains within porous SiO2 mesospheres (MSNs). This engineered architecture achieves up to a 40-fold increase in radioluminescence intensity compared to colloidal NCs, driven by improved retention and conversion of secondary charges, as corroborated by electron release measurements. This approach offers a promising pathway toward developing next-generation nanoscintillators with enhanced performance, with potential applications in high-energy physics, medical imaging, and space technologies.
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Submitted 14 May, 2025;
originally announced May 2025.
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The High Voltage Splitter board for the JUNO SPMT system
Authors:
Pablo Walker,
Juan Pedro Ochoa-Ricoux,
Angel Abusleme,
Agustin Campeny,
Mathieu Bongrand,
Clément Bordereau,
José Busto,
Anatael Cabrera,
Stéphane Callier,
Steven Calvez,
Cédric Cerna,
Thomas Chabot,
Po-An Chen,
Guoming Chen,
Ziliang Chu,
Gérard Claverie,
Christophe De La Taille,
Charles-Edouard Demonchy,
Selma Conforti Di Lorenzo,
Frédéric Druillole,
Lei Fan,
Amélie Fournier,
Yang Han,
Miao He,
Patrick Hellmuth
, et al. (52 additional authors not shown)
Abstract:
The Jiangmen Underground Neutrino Observatory (JUNO) in southern China is designed to study neutrinos from nuclear reactors and natural sources to address fundamental questions in neutrino physics. Achieving its goals requires continuous operation over a 20-year period. The small photomultiplier tube (small PMT or SPMT) system is a subsystem within the experiment composed of 25600 3-inch PMTs and…
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The Jiangmen Underground Neutrino Observatory (JUNO) in southern China is designed to study neutrinos from nuclear reactors and natural sources to address fundamental questions in neutrino physics. Achieving its goals requires continuous operation over a 20-year period. The small photomultiplier tube (small PMT or SPMT) system is a subsystem within the experiment composed of 25600 3-inch PMTs and their associated readout electronics. The High Voltage Splitter (HVS) is the first board on the readout chain of the SPMT system and services the PMTs by providing high voltage for biasing and by decoupling the generated physics signal from the high-voltage bias for readout, which is then fed to the front-end board. The necessity to handle high voltage, manage a large channel count, and operate stably for 20 years imposes significant constraints on the physical design of the HVS. This paper serves as a comprehensive documentation of the HVS board: its role in the SPMT readout system, the challenges in its design, performance and reliability metrics, and the methods employed for production and quality control.
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Submitted 8 May, 2025;
originally announced May 2025.
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Diffuse Optical Ptychography
Authors:
Mingwei He,
Sujit K. Sahoo,
Chengyuan Xiao,
Cuong Dang
Abstract:
Various imaging techniques have significantly enhanced our ability to visualize objects embedded within complex media such as biological tissues, fog, atmosphere, or various turbid media. Optical imaging, in particular, offers multiple advantages, including non-invasive capabilities, absence of ionizing radiation, and high contrast for many biological tissues. However, optical imaging through subs…
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Various imaging techniques have significantly enhanced our ability to visualize objects embedded within complex media such as biological tissues, fog, atmosphere, or various turbid media. Optical imaging, in particular, offers multiple advantages, including non-invasive capabilities, absence of ionizing radiation, and high contrast for many biological tissues. However, optical imaging through substantially thick scattering media remains challenging due to extensive photon diffusion, significantly restricting reconstruction quality and achievable resolution. To address these limitations, we introduce Diffuse Optical Ptychography (DOP), a novel imaging method inspired by ptychography technique, which exploits additional spatial information gained from multiple overlapping illumination patterns. The primary technical innovation of DOP lies in its effective use of overlapping yet minimally correlated illuminations, significantly enhancing reconstruction accuracy and image quality. Compared to existing optical imaging methods through thick diffusive media, DOP achieves superior resolution (down to 1 mm) and reliably reconstructs both binary and grayscale objects embedded within media thicker than 100 transport mean free paths. Importantly, DOP demonstrates robust reconstruction performance both with accurately calibrated diffusion properties and even without prior calibration. Furthermore, the experimental setup for DOP remains straightforward, utilizing only a conventional camera and scanning illumination spots. Our demonstrations underscore the broad potential impact of DOP in applications ranging from medical diagnostics to non-destructive testing, thus opening promising avenues for high-resolution imaging in highly scattering environments.
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Submitted 2 May, 2025;
originally announced May 2025.
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Controlling Droplets at the Tips of Fibers
Authors:
Mengfei He,
Samay Hulikal,
Marianna Marquardt,
Hao Jiang,
Anupam Pandey,
Teng Zhang,
Christian D. Santangelo,
Joseph D. Paulsen
Abstract:
Many complex wetting behaviors of fibrous materials are rooted in the behaviors of individual droplets attached to pairs of fibers. Here, we study the splitting of a droplet held between the tips of two cylindrical fibers. We discover a sharp transition between two post-rupture states, navigated by changing the angle between the rods, in agreement with our bifurcation analysis. Depinning of the br…
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Many complex wetting behaviors of fibrous materials are rooted in the behaviors of individual droplets attached to pairs of fibers. Here, we study the splitting of a droplet held between the tips of two cylindrical fibers. We discover a sharp transition between two post-rupture states, navigated by changing the angle between the rods, in agreement with our bifurcation analysis. Depinning of the bridge contact line can lead to a much larger asymmetry between the volume of liquid left on each rod. This second scenario enables the near-complete transfer of an aqueous glycerol droplet between two identical vinylpolysiloxane fibers. We leverage this response in a device that uses a ruck to pass a droplet along a train of fibers, a proof-of-concept for the geometric control of droplets on deformable, architected surfaces.
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Submitted 12 April, 2025;
originally announced April 2025.
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Stochastic elastohydrodynamics of soft valves
Authors:
Mengfei He,
Sungkyu Cho,
Gianna Dafflisio,
Sitaram Emani,
L. Mahadevan
Abstract:
Soft valves serve to modulate and rectify flows in complex vasculatures across the tree of life, e.g. in the heart of every human reading this. Here we consider a minimal physical model of the heart mitral valve modeled as a flexible conical shell capable of flow rectification via collapse and coaptation in an impinging (reverse) flow. Our experiments show that the complex elastohydrodynamics of c…
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Soft valves serve to modulate and rectify flows in complex vasculatures across the tree of life, e.g. in the heart of every human reading this. Here we consider a minimal physical model of the heart mitral valve modeled as a flexible conical shell capable of flow rectification via collapse and coaptation in an impinging (reverse) flow. Our experiments show that the complex elastohydrodynamics of closure features a noise-activated rectification mechanism. A minimal theoretical model allows us to rationalize our observations while illuminating a dynamical bifurcation driven by stochastic hydrodynamic forces. Our theory also suggests a way to trigger the coaptation of soft valves on demand, which we corroborate using experiments, suggesting a design principle for their efficient operation.
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Submitted 14 April, 2025; v1 submitted 11 April, 2025;
originally announced April 2025.
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Engineering thermal emission with enhanced emissivity and quality factor using bound states in the continuum and electromagnetically-induced absorption
Authors:
Guodong Zhu,
Ikjun Hong,
Theodore Anyika,
Maxwell T. Ugwu,
J. Ryan Nolen,
Mingze He,
Joshua D. Caldwell,
Justus C. Ndukaife
Abstract:
Metal-based thermal metasurfaces exhibit stable spectral characteristics under temperature fluctuations, in contrast to more traditional gray- and near black-bodies, as well as some dielectric metasurfaces, whose emission spectra shift with changing temperatures. However, they often suffer from limited quality (Q) factors due to significant non-radiative ohmic losses. In this study, we address the…
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Metal-based thermal metasurfaces exhibit stable spectral characteristics under temperature fluctuations, in contrast to more traditional gray- and near black-bodies, as well as some dielectric metasurfaces, whose emission spectra shift with changing temperatures. However, they often suffer from limited quality (Q) factors due to significant non-radiative ohmic losses. In this study, we address the challenge of achieving high emissivity and Q-factors in metal-based thermal emitters. By leveraging the coupling between a magnetic dipole resonance and two bound-state-in-continuum (BIC) resonances to achieve electromagnetically induced absorption (EIA) in an asymmetric metallic ring structure, we design a metal-based thermal metasurface with a near-unity emissivity (0.96) and a Q factor as high as 320 per simulations. Experimental validation yields an emissivity of 0.82 and a Q factor of 202, representing an approximately five-fold improvement in the experimentally measured Q factor compared to the state-of-the-art metal-based thermal metasurfaces. Our work offers a promising approach for developing efficient, narrow-band, directional thermal emitters with stable emission spectra across a wide temperature range.
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Submitted 1 April, 2025;
originally announced April 2025.
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European Contributions to Fermilab Accelerator Upgrades and Facilities for the DUNE Experiment
Authors:
DUNE Collaboration,
A. Abed Abud,
R. Acciarri,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
D. Adams,
M. Adinolfi,
C. Adriano,
A. Aduszkiewicz,
J. Aguilar,
F. Akbar,
F. Alemanno,
N. S. Alex,
K. Allison,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
A. Aman,
H. Amar,
P. Amedo,
J. Anderson,
D. A. Andrade
, et al. (1322 additional authors not shown)
Abstract:
The Proton Improvement Plan (PIP-II) to the FNAL accelerator chain and the Long-Baseline Neutrino Facility (LBNF) will provide the world's most intense neutrino beam to the Deep Underground Neutrino Experiment (DUNE) enabling a wide-ranging physics program. This document outlines the significant contributions made by European national laboratories and institutes towards realizing the first phase o…
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The Proton Improvement Plan (PIP-II) to the FNAL accelerator chain and the Long-Baseline Neutrino Facility (LBNF) will provide the world's most intense neutrino beam to the Deep Underground Neutrino Experiment (DUNE) enabling a wide-ranging physics program. This document outlines the significant contributions made by European national laboratories and institutes towards realizing the first phase of the project with a 1.2 MW neutrino beam. Construction of this first phase is well underway. For DUNE Phase II, this will be closely followed by an upgrade of the beam power to > 2 MW, for which the European groups again have a key role and which will require the continued support of the European community for machine aspects of neutrino physics. Beyond the neutrino beam aspects, LBNF is also responsible for providing unique infrastructure to install and operate the DUNE neutrino detectors at FNAL and at the Sanford Underground Research Facility (SURF). The cryostats for the first two Liquid Argon Time Projection Chamber detector modules at SURF, a contribution of CERN to LBNF, are central to the success of the ongoing execution of DUNE Phase I. Likewise, successful and timely procurement of cryostats for two additional detector modules at SURF will be critical to the success of DUNE Phase II and the overall physics program. The DUNE Collaboration is submitting four main contributions to the 2026 Update of the European Strategy for Particle Physics process. This paper is being submitted to the 'Accelerator technologies' and 'Projects and Large Experiments' streams. Additional inputs related to the DUNE science program, DUNE detector technologies and R&D, and DUNE software and computing, are also being submitted to other streams.
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Submitted 31 March, 2025;
originally announced March 2025.
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DUNE Software and Computing Research and Development
Authors:
DUNE Collaboration,
A. Abed Abud,
R. Acciarri,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
D. Adams,
M. Adinolfi,
C. Adriano,
A. Aduszkiewicz,
J. Aguilar,
F. Akbar,
F. Alemanno,
N. S. Alex,
K. Allison,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
A. Aman,
H. Amar,
P. Amedo,
J. Anderson,
D. A. Andrade
, et al. (1322 additional authors not shown)
Abstract:
The international collaboration designing and constructing the Deep Underground Neutrino Experiment (DUNE) at the Long-Baseline Neutrino Facility (LBNF) has developed a two-phase strategy toward the implementation of this leading-edge, large-scale science project. The ambitious physics program of Phase I and Phase II of DUNE is dependent upon deployment and utilization of significant computing res…
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The international collaboration designing and constructing the Deep Underground Neutrino Experiment (DUNE) at the Long-Baseline Neutrino Facility (LBNF) has developed a two-phase strategy toward the implementation of this leading-edge, large-scale science project. The ambitious physics program of Phase I and Phase II of DUNE is dependent upon deployment and utilization of significant computing resources, and successful research and development of software (both infrastructure and algorithmic) in order to achieve these scientific goals. This submission discusses the computing resources projections, infrastructure support, and software development needed for DUNE during the coming decades as an input to the European Strategy for Particle Physics Update for 2026. The DUNE collaboration is submitting four main contributions to the 2026 Update of the European Strategy for Particle Physics process. This submission to the 'Computing' stream focuses on DUNE software and computing. Additional inputs related to the DUNE science program, DUNE detector technologies and R&D, and European contributions to Fermilab accelerator upgrades and facilities for the DUNE experiment, are also being submitted to other streams.
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Submitted 31 March, 2025;
originally announced March 2025.
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The DUNE Phase II Detectors
Authors:
DUNE Collaboration,
A. Abed Abud,
R. Acciarri,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
D. Adams,
M. Adinolfi,
C. Adriano,
A. Aduszkiewicz,
J. Aguilar,
F. Akbar,
F. Alemanno,
N. S. Alex,
K. Allison,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
A. Aman,
H. Amar,
P. Amedo,
J. Anderson,
D. A. Andrade
, et al. (1322 additional authors not shown)
Abstract:
The international collaboration designing and constructing the Deep Underground Neutrino Experiment (DUNE) at the Long-Baseline Neutrino Facility (LBNF) has developed a two-phase strategy for the implementation of this leading-edge, large-scale science project. The 2023 report of the US Particle Physics Project Prioritization Panel (P5) reaffirmed this vision and strongly endorsed DUNE Phase I and…
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The international collaboration designing and constructing the Deep Underground Neutrino Experiment (DUNE) at the Long-Baseline Neutrino Facility (LBNF) has developed a two-phase strategy for the implementation of this leading-edge, large-scale science project. The 2023 report of the US Particle Physics Project Prioritization Panel (P5) reaffirmed this vision and strongly endorsed DUNE Phase I and Phase II, as did the previous European Strategy for Particle Physics. The construction of DUNE Phase I is well underway. DUNE Phase II consists of a third and fourth far detector module, an upgraded near detector complex, and an enhanced > 2 MW beam. The fourth FD module is conceived as a 'Module of Opportunity', aimed at supporting the core DUNE science program while also expanding the physics opportunities with more advanced technologies. The DUNE collaboration is submitting four main contributions to the 2026 Update of the European Strategy for Particle Physics process. This submission to the 'Detector instrumentation' stream focuses on technologies and R&D for the DUNE Phase II detectors. Additional inputs related to the DUNE science program, DUNE software and computing, and European contributions to Fermilab accelerator upgrades and facilities for the DUNE experiment, are also being submitted to other streams.
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Submitted 29 March, 2025;
originally announced March 2025.
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Simulation of the Background from $^{13}$C$(α, n)^{16}$O Reaction in the JUNO Scintillator
Authors:
JUNO Collaboration,
Thomas Adam,
Kai Adamowicz,
Shakeel Ahmad,
Rizwan Ahmed,
Sebastiano Aiello,
Fengpeng An,
Costas Andreopoulos,
Giuseppe Andronico,
Nikolay Anfimov,
Vito Antonelli,
Tatiana Antoshkina,
João Pedro Athayde Marcondes de André,
Didier Auguste,
Weidong Bai,
Nikita Balashov,
Andrea Barresi,
Davide Basilico,
Eric Baussan,
Marco Beretta,
Antonio Bergnoli,
Nikita Bessonov,
Daniel Bick,
Lukas Bieger,
Svetlana Biktemerova
, et al. (608 additional authors not shown)
Abstract:
Large-scale organic liquid scintillator detectors are highly efficient in the detection of MeV-scale electron antineutrinos. These signal events can be detected through inverse beta decay on protons, which produce a positron accompanied by a neutron. A noteworthy background for antineutrinos coming from nuclear power reactors and from the depths of the Earth (geoneutrinos) is generated by ($α, n$)…
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Large-scale organic liquid scintillator detectors are highly efficient in the detection of MeV-scale electron antineutrinos. These signal events can be detected through inverse beta decay on protons, which produce a positron accompanied by a neutron. A noteworthy background for antineutrinos coming from nuclear power reactors and from the depths of the Earth (geoneutrinos) is generated by ($α, n$) reactions. In organic liquid scintillator detectors, $α$ particles emitted from intrinsic contaminants such as $^{238}$U, $^{232}$Th, and $^{210}$Pb/$^{210}$Po, can be captured on $^{13}$C nuclei, followed by the emission of a MeV-scale neutron. Three distinct interaction mechanisms can produce prompt energy depositions preceding the delayed neutron capture, leading to a pair of events correlated in space and time within the detector. Thus, ($α, n$) reactions represent an indistinguishable background in liquid scintillator-based antineutrino detectors, where their expected rate and energy spectrum are typically evaluated via Monte Carlo simulations. This work presents results from the open-source SaG4n software, used to calculate the expected energy depositions from the neutron and any associated de-excitation products. Also simulated is a detailed detector response to these interactions, using a dedicated Geant4-based simulation software from the JUNO experiment. An expected measurable $^{13}$C$(α, n)^{16}$O event rate and reconstructed prompt energy spectrum with associated uncertainties, are presented in the context of JUNO, however, the methods and results are applicable and relevant to other organic liquid scintillator neutrino detectors.
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Submitted 2 May, 2025; v1 submitted 2 March, 2025;
originally announced March 2025.
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Spatial Optical Simulator for Classical Statistical Models
Authors:
Song-Tao Yu,
Ming-Gen He,
Sheng Fang,
Youjin Deng,
Zhen-Sheng Yuan
Abstract:
Optical simulators for the Ising model have demonstrated great promise for solving challenging problems in physics and beyond. Here, we develop a spatial optical simulator for a variety of classical statistical systems, including the clock, $XY$, Potts, and Heisenberg models, utilizing a digital micromirror device composed of a large number of tiny mirrors. Spins, with desired amplitudes or phases…
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Optical simulators for the Ising model have demonstrated great promise for solving challenging problems in physics and beyond. Here, we develop a spatial optical simulator for a variety of classical statistical systems, including the clock, $XY$, Potts, and Heisenberg models, utilizing a digital micromirror device composed of a large number of tiny mirrors. Spins, with desired amplitudes or phases of the statistical models, are precisely encoded by a patch of mirrors with a superpixel approach. Then, by modulating the light field in a sequence of designed patterns, the spin-spin interaction is realized in such a way that the Hamiltonian symmetries are preserved. We successfully simulate statistical systems on a fully connected network, with ferromagnetic or Mattis-type random interactions, and observe the corresponding phase transitions between the paramagnetic, and the ferromagnetic or spin-glass phases. Our results largely extend the research scope of spatial optical simulators and their versatile applications.
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Submitted 17 December, 2024;
originally announced December 2024.
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On-demand Quick Metasurface Design with Neighborhood Attention Transformer
Authors:
Zhi Sun,
Tianyue Li,
Shiqi Kuang,
Xue Yun,
Minru He,
Boyan Fu,
Yunlai Fu,
Tianyu Zhao,
Shaowei Wang,
Yansheng Liang,
Shuming Wang,
Ming Lei
Abstract:
Metasurfaces are reshaping traditional optical paradigms and are increasingly required in complex applications that demand substantial computational resources to numerically solve Maxwell's equations-particularly for large-scale systems, inhomogeneous media, and densely packed metadevices. Conventional forward design using electromagnetic solvers is based on specific approximations, which may not…
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Metasurfaces are reshaping traditional optical paradigms and are increasingly required in complex applications that demand substantial computational resources to numerically solve Maxwell's equations-particularly for large-scale systems, inhomogeneous media, and densely packed metadevices. Conventional forward design using electromagnetic solvers is based on specific approximations, which may not effectively address complex problems. In contrast, existing inverse design methods are a stepwise process that is often time-consuming and involves repetitive computations. Here, we present an inverse design approach utilizing a surrogate Neighborhood Attention Transformer, MetaE-former, to predict the performance of metasurfaces with ultrafast speed and high accuracy. This method achieves global solutions for hundreds of nanostructures simultaneously, providing up to a 250,000-fold speedup compared with solving for individual meta-atoms based on the FDTD method. As examples, we demonstrate a binarized high-numerical-aperture (about 1.31) metalens and several optimized structured-light meta-generators. Our method significantly improves the beam shaping adaptability with metasurfaces and paves the way for fast designing of large-scale metadevices for shaping extreme light fields with high accuracy.
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Submitted 11 December, 2024;
originally announced December 2024.
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Constructing accurate machine-learned potentials and performing highly efficient atomistic simulations to predict structural and thermal properties
Authors:
Junlan Liu,
Qian Yin,
Mengshu He,
Jun Zhou
Abstract:
The $\text{Cu}_7\text{P}\text{S}_6$ compound has garnered significant attention due to its potential in thermoelectric applications. In this study, we introduce a neuroevolution potential (NEP), trained on a dataset generated from ab initio molecular dynamics (AIMD) simulations, using the moment tensor potential (MTP) as a reference. The low root mean square errors (RMSEs) for total energy and ato…
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The $\text{Cu}_7\text{P}\text{S}_6$ compound has garnered significant attention due to its potential in thermoelectric applications. In this study, we introduce a neuroevolution potential (NEP), trained on a dataset generated from ab initio molecular dynamics (AIMD) simulations, using the moment tensor potential (MTP) as a reference. The low root mean square errors (RMSEs) for total energy and atomic forces demonstrate the high accuracy and transferability of both the MTP and NEP. We further calculate the phonon density of states (DOS) and radial distribution function (RDF) using both machine learning potentials, comparing the results to density functional theory (DFT) calculations. While the MTP potential offers slightly higher accuracy, the NEP achieves a remarkable 41-fold increase in computational speed. These findings provide detailed microscopic insights into the dynamics and rapid Cu-ion diffusion, paving the way for future studies on Cu-based solid electrolytes and their applications in energy devices.
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Submitted 16 November, 2024;
originally announced November 2024.
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Cities Reconceptualized: Unveiling Hidden Uniform Urban Shape through Commute Flow Modeling in Major US Cities
Authors:
Margarita Mishina,
Mingyi He,
Venu Garikapati,
Stanislav Sobolevsky
Abstract:
Urban development is shaped by historical, geographical, and economic factors, presenting challenges for planners in understanding urban form. This study models commute flows across multiple U.S. cities, uncovering consistent patterns in urban population distributions and commuting behaviors. By embedding urban locations to reflect mobility networks, we observe that population distributions across…
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Urban development is shaped by historical, geographical, and economic factors, presenting challenges for planners in understanding urban form. This study models commute flows across multiple U.S. cities, uncovering consistent patterns in urban population distributions and commuting behaviors. By embedding urban locations to reflect mobility networks, we observe that population distributions across redefined urban spaces tend to approximate log-normal distributions, in contrast to the often irregular distributions found in geographical space. This divergence suggests that natural and historical constraints shape spatial population patterns, while, under ideal conditions, urban organization may naturally align with log-normal distribution. A theoretical model using preferential attachment and random walks supports the emergence of this distribution in urban settings. These findings reveal a fundamental organizing principle in urban systems that, while not always visible geographically, consistently governs population flows and distributions. This insight into the underlying urban structure can inform planners seeking to design efficient, resilient cities.
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Submitted 8 November, 2024;
originally announced November 2024.
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Molecular Dynamics and Machine Learning Unlock Possibilities in Beauty Design -- A Perspective
Authors:
Yuzhi Xu,
Haowei Ni,
Qinhui Gao,
Chia-Hua Chang,
Yanran Huo,
Fanyu Zhao,
Shiyu Hu,
Wei Xia,
Yike Zhang,
Radu Grovu,
Min He,
John. Z. H. Zhang,
Yuanqing Wang
Abstract:
Computational molecular design -- the endeavor to design molecules, with various missions, aided by machine learning and molecular dynamics approaches, has been widely applied to create valuable new molecular entities, from small molecule therapeutics to protein biologics. In the small data regime, physics-based approaches model the interaction between the molecule being designed and proteins of k…
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Computational molecular design -- the endeavor to design molecules, with various missions, aided by machine learning and molecular dynamics approaches, has been widely applied to create valuable new molecular entities, from small molecule therapeutics to protein biologics. In the small data regime, physics-based approaches model the interaction between the molecule being designed and proteins of key physiological functions, providing structural insights into the mechanism. When abundant data has been collected, a quantitative structure-activity relationship (QSAR) can be more directly constructed from experimental data, from which machine learning can distill key insights to guide the design of the next round of experiment design. Machine learning methodologies can also facilitate physical modeling, from improving the accuracy of force fields and extending them to unseen chemical spaces, to more directly enhancing the sampling on the conformational spaces. We argue that these techniques are mature enough to be applied to not just extend the longevity of life, but the beauty it manifests. In this perspective, we review the current frontiers in the research \& development of skin care products, as well as the statistical and physical toolbox applicable to addressing the challenges in this industry. Feasible interdisciplinary research projects are proposed to harness the power of machine learning tools to design innovative, effective, and inexpensive skin care products.
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Submitted 28 October, 2024; v1 submitted 8 October, 2024;
originally announced October 2024.
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The track-length extension fitting algorithm for energy measurement of interacting particles in liquid argon TPCs and its performance with ProtoDUNE-SP data
Authors:
DUNE Collaboration,
A. Abed Abud,
B. Abi,
R. Acciarri,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
D. Adams,
M. Adinolfi,
C. Adriano,
A. Aduszkiewicz,
J. Aguilar,
F. Akbar,
N. S. Alex,
K. Allison,
S. Alonso Monsalve,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
H. Amar,
P. Amedo,
J. Anderson,
C. Andreopoulos
, et al. (1348 additional authors not shown)
Abstract:
This paper introduces a novel track-length extension fitting algorithm for measuring the kinetic energies of inelastically interacting particles in liquid argon time projection chambers (LArTPCs). The algorithm finds the most probable offset in track length for a track-like object by comparing the measured ionization density as a function of position with a theoretical prediction of the energy los…
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This paper introduces a novel track-length extension fitting algorithm for measuring the kinetic energies of inelastically interacting particles in liquid argon time projection chambers (LArTPCs). The algorithm finds the most probable offset in track length for a track-like object by comparing the measured ionization density as a function of position with a theoretical prediction of the energy loss as a function of the energy, including models of electron recombination and detector response. The algorithm can be used to measure the energies of particles that interact before they stop, such as charged pions that are absorbed by argon nuclei. The algorithm's energy measurement resolutions and fractional biases are presented as functions of particle kinetic energy and number of track hits using samples of stopping secondary charged pions in data collected by the ProtoDUNE-SP detector, and also in a detailed simulation. Additional studies describe the impact of the dE/dx model on energy measurement performance. The method described in this paper to characterize the energy measurement performance can be repeated in any LArTPC experiment using stopping secondary charged pions.
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Submitted 26 December, 2024; v1 submitted 26 September, 2024;
originally announced September 2024.
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DUNE Phase II: Scientific Opportunities, Detector Concepts, Technological Solutions
Authors:
DUNE Collaboration,
A. Abed Abud,
B. Abi,
R. Acciarri,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
D. Adams,
M. Adinolfi,
C. Adriano,
A. Aduszkiewicz,
J. Aguilar,
F. Akbar,
K. Allison,
S. Alonso Monsalve,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
H. Amar,
P. Amedo,
J. Anderson,
C. Andreopoulos,
M. Andreotti
, et al. (1347 additional authors not shown)
Abstract:
The international collaboration designing and constructing the Deep Underground Neutrino Experiment (DUNE) at the Long-Baseline Neutrino Facility (LBNF) has developed a two-phase strategy toward the implementation of this leading-edge, large-scale science project. The 2023 report of the US Particle Physics Project Prioritization Panel (P5) reaffirmed this vision and strongly endorsed DUNE Phase I…
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The international collaboration designing and constructing the Deep Underground Neutrino Experiment (DUNE) at the Long-Baseline Neutrino Facility (LBNF) has developed a two-phase strategy toward the implementation of this leading-edge, large-scale science project. The 2023 report of the US Particle Physics Project Prioritization Panel (P5) reaffirmed this vision and strongly endorsed DUNE Phase I and Phase II, as did the European Strategy for Particle Physics. While the construction of the DUNE Phase I is well underway, this White Paper focuses on DUNE Phase II planning. DUNE Phase-II consists of a third and fourth far detector (FD) module, an upgraded near detector complex, and an enhanced 2.1 MW beam. The fourth FD module is conceived as a "Module of Opportunity", aimed at expanding the physics opportunities, in addition to supporting the core DUNE science program, with more advanced technologies. This document highlights the increased science opportunities offered by the DUNE Phase II near and far detectors, including long-baseline neutrino oscillation physics, neutrino astrophysics, and physics beyond the standard model. It describes the DUNE Phase II near and far detector technologies and detector design concepts that are currently under consideration. A summary of key R&D goals and prototyping phases needed to realize the Phase II detector technical designs is also provided. DUNE's Phase II detectors, along with the increased beam power, will complete the full scope of DUNE, enabling a multi-decadal program of groundbreaking science with neutrinos.
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Submitted 22 August, 2024;
originally announced August 2024.
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Imaginary Poynting momentum driven particle rotation by cylindrically polarized Gaussian beams
Authors:
Xue Yun,
Yansheng Liang,
Linquan Guo,
Minru He,
Tianyu Zhao,
Shaowei Wang,
Ming Lei
Abstract:
Imaginary Poynting momentum (IPM) provides a new degree of freedom for particle manipulation. However, the application of IPM in experiments has been largely unexplored. Here, we demonstrate the IPM driven particle rotation by cylindrically polarized Gaussian beams with no spin or orbital angular momentum. Theoretical analysis and experimental measurements demonstrate that gold microparticles will…
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Imaginary Poynting momentum (IPM) provides a new degree of freedom for particle manipulation. However, the application of IPM in experiments has been largely unexplored. Here, we demonstrate the IPM driven particle rotation by cylindrically polarized Gaussian beams with no spin or orbital angular momentum. Theoretical analysis and experimental measurements demonstrate that gold microparticles will be rotated in the azimuthal direction while confined in the radial direction. We achieved controllable rotation of the particle by tuning the cylindrical polarization state. Interestingly, the transfer of IPM to a gold particle is demonstrated to be competitive with that of spin angular momentum. These findings hold promising in light-matter interactions and particle manipulations.
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Submitted 14 August, 2024;
originally announced August 2024.
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First Measurement of the Total Inelastic Cross-Section of Positively-Charged Kaons on Argon at Energies Between 5.0 and 7.5 GeV
Authors:
DUNE Collaboration,
A. Abed Abud,
B. Abi,
R. Acciarri,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
D. Adams,
M. Adinolfi,
C. Adriano,
A. Aduszkiewicz,
J. Aguilar,
F. Akbar,
K. Allison,
S. Alonso Monsalve,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
H. Amar,
P. Amedo,
J. Anderson,
C. Andreopoulos,
M. Andreotti
, et al. (1341 additional authors not shown)
Abstract:
ProtoDUNE Single-Phase (ProtoDUNE-SP) is a 770-ton liquid argon time projection chamber that operated in a hadron test beam at the CERN Neutrino Platform in 2018. We present a measurement of the total inelastic cross section of charged kaons on argon as a function of kaon energy using 6 and 7 GeV/$c$ beam momentum settings. The flux-weighted average of the extracted inelastic cross section at each…
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ProtoDUNE Single-Phase (ProtoDUNE-SP) is a 770-ton liquid argon time projection chamber that operated in a hadron test beam at the CERN Neutrino Platform in 2018. We present a measurement of the total inelastic cross section of charged kaons on argon as a function of kaon energy using 6 and 7 GeV/$c$ beam momentum settings. The flux-weighted average of the extracted inelastic cross section at each beam momentum setting was measured to be 380$\pm$26 mbarns for the 6 GeV/$c$ setting and 379$\pm$35 mbarns for the 7 GeV/$c$ setting.
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Submitted 1 August, 2024;
originally announced August 2024.
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Supernova Pointing Capabilities of DUNE
Authors:
DUNE Collaboration,
A. Abed Abud,
B. Abi,
R. Acciarri,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
D. Adams,
M. Adinolfi,
C. Adriano,
A. Aduszkiewicz,
J. Aguilar,
B. Aimard,
F. Akbar,
K. Allison,
S. Alonso Monsalve,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
H. Amar,
P. Amedo,
J. Anderson,
D. A. Andrade
, et al. (1340 additional authors not shown)
Abstract:
The determination of the direction of a stellar core collapse via its neutrino emission is crucial for the identification of the progenitor for a multimessenger follow-up. A highly effective method of reconstructing supernova directions within the Deep Underground Neutrino Experiment (DUNE) is introduced. The supernova neutrino pointing resolution is studied by simulating and reconstructing electr…
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The determination of the direction of a stellar core collapse via its neutrino emission is crucial for the identification of the progenitor for a multimessenger follow-up. A highly effective method of reconstructing supernova directions within the Deep Underground Neutrino Experiment (DUNE) is introduced. The supernova neutrino pointing resolution is studied by simulating and reconstructing electron-neutrino charged-current absorption on 40Ar and elastic scattering of neutrinos on electrons. Procedures to reconstruct individual interactions, including a newly developed technique called ``brems flipping'', as well as the burst direction from an ensemble of interactions are described. Performance of the burst direction reconstruction is evaluated for supernovae happening at a distance of 10 kpc for a specific supernova burst flux model. The pointing resolution is found to be 3.4 degrees at 68% coverage for a perfect interaction-channel classification and a fiducial mass of 40 kton, and 6.6 degrees for a 10 kton fiducial mass respectively. Assuming a 4% rate of charged-current interactions being misidentified as elastic scattering, DUNE's burst pointing resolution is found to be 4.3 degrees (8.7 degrees) at 68% coverage.
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Submitted 24 December, 2025; v1 submitted 14 July, 2024;
originally announced July 2024.
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A response to commenter Ke Lan's comment on our paper published in Nature Communications (2023)14:5782 by J. Yan et al
Authors:
Ji Yan,
Jiwei Li,
X. T. He,
Lifeng Wang,
Yaohua Chen,
Feng Wang,
Xiaoying Han,
Kaiqiang Pan,
Juxi Liang,
Yulong Li,
Zanyang Guan,
Xiangming Liu,
Xingsen Che,
Zhongjing Chen,
Xing Zhang,
Yan Xu,
Bin Li,
Minging He,
Hongbo Cai,
Liang. Hao,
Zhanjun Liu,
Chunyang Zheng,
Zhensheng Dai,
Zhengfeng Fan,
Bin Qiao
, et al. (4 additional authors not shown)
Abstract:
A response to commenter Ke Lan's comment on our paper published in Nature Communications (2023)14:5782 by J. Yan et al
A response to commenter Ke Lan's comment on our paper published in Nature Communications (2023)14:5782 by J. Yan et al
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Submitted 25 June, 2024;
originally announced June 2024.
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Nonlinear Interactions of Planetary-Scale Waves in Mesospheric Winds Observed at 52°N Latitude and Two Longitudes
Authors:
Maosheng He,
Jeffrey M. Forbes,
Gunter Stober,
Christoph Jacobi,
Guozhu Li,
Libo Liu,
Jiyao Xu
Abstract:
Nine years of mesospheric wind data from two meteor radars at 52°N latitude were analyzed to investigate planetary waves (PWs) and tides by estimating their zonal wavenumber through longitudinal phase differences. Our results reveal that PW normal modes (NMs) primarily drive multi-day oscillations, showing seasonal variability and statistical associations with Sudden Stratospheric Warming (SSW) ev…
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Nine years of mesospheric wind data from two meteor radars at 52°N latitude were analyzed to investigate planetary waves (PWs) and tides by estimating their zonal wavenumber through longitudinal phase differences. Our results reveal that PW normal modes (NMs) primarily drive multi-day oscillations, showing seasonal variability and statistical associations with Sudden Stratospheric Warming (SSW) events. Specifically, a significant 6-day NM emerges in April, followed by predominant 4- and 2-day NMs until June, with peaks of 2-, 4-, and 6-day NMs spanning July to October. Furthermore, our study provides the first observational verification of frequency and zonal wavenumber of over ten secondary waves from nonlinear interactions among planetary-scale waves. One notable finding is the prevalence of non-migrating components in winter 24-hour and summer 8-hour tides, attributed to these nonlinear interactions. Our findings underscore the diverse nonlinear dynamics of planetary-scale waves, triggering a variety of periodic oscillations.
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Submitted 11 June, 2024; v1 submitted 9 June, 2024;
originally announced June 2024.
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Realization of cold atom gyroscope in space
Authors:
Jinting Li,
Xi Chen,
Danfang Zhang,
Wenzhang Wang,
Yang Zhou,
Meng He,
Jie Fang,
Lin Zhou,
Chuan He,
Junjie Jiang,
Huanyao Sun,
Qunfeng Chen,
Lei Qin,
Xiao Li,
Yibo Wang,
Xiaowei Zhang,
Jiaqi Zhong,
Runbing Li,
Meizhen An,
Long Zhang,
Shuquan Wang,
Zongfeng Li,
Jin Wang,
Mingsheng Zhan
Abstract:
High-precision gyroscopes in space are essential for fundamental physics research and navigation. Due to its potential high precision, the cold atom gyroscope is expected to be the next generation of gyroscopes in space. Here, we report the first realization of a cold atom gyroscope, which was demonstrated by the atom interferometer installed in the China Space Station (CSS) as a payload. By compe…
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High-precision gyroscopes in space are essential for fundamental physics research and navigation. Due to its potential high precision, the cold atom gyroscope is expected to be the next generation of gyroscopes in space. Here, we report the first realization of a cold atom gyroscope, which was demonstrated by the atom interferometer installed in the China Space Station (CSS) as a payload. By compensating for CSS's high dynamic rotation rate using a built-in piezoelectric mirror, spatial interference fringes in the interferometer are successfully obtained. Then, the optimized ratio of the Raman laser's angles is derived, the coefficients of the piezoelectric mirror are self-calibrated in orbit, and various systemic effects are corrected. We achieve a rotation measurement resolution of 50*10^-6 rad/s for a single shot and 17*10^-6 rad/s for an average number of 32. The measured rotation is (-1142+/-29)*10^-6 rad/s and is compatible with that recorded by the classical gyroscope of the CSS. This study paves the way for developing high-precision cold atom gyroscopes in space.
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Submitted 14 September, 2024; v1 submitted 31 May, 2024;
originally announced May 2024.
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A critical comparison of the implementation of granular pressure gradient term in Euler-Euler simulation of gas-solid flows
Authors:
Yige Liu,
Mingming He,
Jianhua Chen,
Wen Li,
Bidan Zhao,
Ji Xu,
Junwu Wang
Abstract:
Numerical solution of Euler-Euler model using different in-house, open source and commercial software can generate significantly different results, even when the governing equations and the initial and boundary conditions are exactly same. Unfortunately, the underlying reasons have not been identified yet. In this article, three methods for calculating the granular pressure gradient term are prese…
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Numerical solution of Euler-Euler model using different in-house, open source and commercial software can generate significantly different results, even when the governing equations and the initial and boundary conditions are exactly same. Unfortunately, the underlying reasons have not been identified yet. In this article, three methods for calculating the granular pressure gradient term are presented for two-fluid model of gas-solid flows and implemented implicitly or explicitly into the solver in OpenFOAM: Method I assumes that the granular pressure gradient is equal to the elastic modulus plus the solid concentration gradient; Method II directly calculates the gradient using a difference scheme; Method III, which is proposed in this work, calculates the gradient as the sum of two partial derivatives: one related to the solid volume fraction and the other related to the granular energy. Obviously, only Methods II and III are consistent with kinetic theory of granular flow. It was found that the difference between all methods is small for bubbling fluidization. While for circulating fluidization, both methods II and III are capable of capturing non-uniform structures and producing superior results over Method I. The contradictory conclusions made from the simulation of different fluidization regimes is due to the different contribution of the term related to the granular energy gradient. Present study concludes that the implementation method of granular pressure gradient may have a significant impact on hydrodynamics and is probably a key factor contributing to the observed differences between different simulation software.
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Submitted 31 May, 2024;
originally announced May 2024.
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Prediction of Energy Resolution in the JUNO Experiment
Authors:
JUNO Collaboration,
Angel Abusleme,
Thomas Adam,
Kai Adamowicz,
Shakeel Ahmad,
Rizwan Ahmed,
Sebastiano Aiello,
Fengpeng An,
Qi An,
Giuseppe Andronico,
Nikolay Anfimov,
Vito Antonelli,
Tatiana Antoshkina,
João Pedro Athayde Marcondes de André,
Didier Auguste,
Weidong Bai,
Nikita Balashov,
Wander Baldini,
Andrea Barresi,
Davide Basilico,
Eric Baussan,
Marco Bellato,
Marco Beretta,
Antonio Bergnoli,
Daniel Bick
, et al. (629 additional authors not shown)
Abstract:
This paper presents an energy resolution study of the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3\% at 1~MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components o…
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This paper presents an energy resolution study of the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3\% at 1~MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of the liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The results of study reveal an energy resolution of 2.95\% at 1~MeV. Furthermore, this study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data collection. Moreover, it provides a guideline for comprehending the energy resolution characteristics of liquid scintillator-based detectors.
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Submitted 9 January, 2025; v1 submitted 28 May, 2024;
originally announced May 2024.
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Identifying L-H transition in HL-2A through deep learning
Authors:
Meihuizi He,
Songfen Liu,
Fan Xia,
Zongyu Yang,
Wulyu Zhong
Abstract:
During the operation of tokamak devices, addressing the thermal load issues caused by Edge Localized Modes (ELMs) eruption is crucial. Ideally, mitigation and suppression measures for ELMs should be promptly initiated as soon as the first low-to-high confinement (L-H) transition occurs, which necessitates the real-time monitoring and accurate identification of the L-H transition process. Motivated…
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During the operation of tokamak devices, addressing the thermal load issues caused by Edge Localized Modes (ELMs) eruption is crucial. Ideally, mitigation and suppression measures for ELMs should be promptly initiated as soon as the first low-to-high confinement (L-H) transition occurs, which necessitates the real-time monitoring and accurate identification of the L-H transition process. Motivated by this, and by recent deep learning boom, we propose a deep learning-based L-H transition identification algorithm on HL-2A tokamak. In this work, we have constructed a neural network comprising layers of Residual Long Short-Term Memory (LSTM) and Temporal Convolutional Network (TCN). Unlike previous work based on recognition for ELMs by slice, this method implements recognition on L-H transition process before the first ELMs crash. Therefore the mitigation techniques can be triggered in time to suppress the initial ELMs bursts. In order to further explain the effectiveness of the algorithm, we developed a series of evaluation indicators by shots, and the results show that this algorithm can provide necessary reference for the mitigation and suppression system.
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Submitted 17 May, 2024;
originally announced May 2024.
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Constraints on the Blazar-Boosted Dark Matter from the CDEX-10 Experiment
Authors:
R. Xu,
L. T. Yang,
Q. Yue,
K. J. Kang,
Y. J. Li,
H. P. An,
Greeshma C.,
J. P. Chang,
Y. H. Chen,
J. P. Cheng,
W. H. Dai,
Z. Deng,
C. H. Fang,
X. P. Geng,
H. Gong,
Q. J. Guo,
T. Guo,
X. Y. Guo,
L. He,
S. M. He,
J. W. Hu,
H. X. Huang,
T. C. Huang,
L. Jiang,
S. Karmakar
, et al. (59 additional authors not shown)
Abstract:
We report new constraints on light dark matter (DM) boosted by blazars using the 205.4 kg day data from the CDEX-10 experiment located at the China Jinping Underground Laboratory. Two representative blazars, TXS 0506+56 and BL Lacertae are studied. The results derived from TXS 0506+56 exclude DM-nucleon elastic scattering cross sections from $4.6\times 10^{-33}\ \rm cm^2$ to…
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We report new constraints on light dark matter (DM) boosted by blazars using the 205.4 kg day data from the CDEX-10 experiment located at the China Jinping Underground Laboratory. Two representative blazars, TXS 0506+56 and BL Lacertae are studied. The results derived from TXS 0506+56 exclude DM-nucleon elastic scattering cross sections from $4.6\times 10^{-33}\ \rm cm^2$ to $1\times10^{-26}\ \rm cm^2$ for DM masses between 10 keV and 1 GeV, and the results derived from BL Lacertae exclude DM-nucleon elastic scattering cross sections from $2.4\times 10^{-34}\ \rm cm^2$ to $1\times10^{-26}\ \rm cm^2$ for the same range of DM masses. The constraints correspond to the best sensitivities among solid-state detector experiments in the sub-MeV mass range.
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Submitted 29 March, 2024;
originally announced March 2024.
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Probing Dark Matter Particles from Evaporating Primordial Black Holes via Electron Scattering in the CDEX-10 Experiment
Authors:
Z. H. Zhang,
L. T. Yang,
Q. Yue,
K. J. Kang,
Y. J. Li,
H. P. An,
Greeshma C.,
J. P. Chang,
Y. H. Chen,
J. P. Cheng,
W. H. Dai,
Z. Deng,
C. H. Fang,
X. P. Geng,
H. Gong,
Q. J. Guo,
T. Guo,
X. Y. Guo,
L. He,
S. M. He,
J. W. Hu,
H. X. Huang,
T. C. Huang,
L. Jiang,
S. Karmakar
, et al. (59 additional authors not shown)
Abstract:
Dark matter (DM) is a major constituent of the Universe. However, no definite evidence of DM particles (denoted as ``$χ$") has been found in DM direct detection (DD) experiments to date. There is a novel concept of detecting $χ$ from evaporating primordial black holes (PBHs). We search for $χ$ emitted from PBHs by investigating their interaction with target electrons. The examined PBH masses range…
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Dark matter (DM) is a major constituent of the Universe. However, no definite evidence of DM particles (denoted as ``$χ$") has been found in DM direct detection (DD) experiments to date. There is a novel concept of detecting $χ$ from evaporating primordial black holes (PBHs). We search for $χ$ emitted from PBHs by investigating their interaction with target electrons. The examined PBH masses range from 1$\times$10$^{15}$ to 7$\times$10$^{16}$ g under the current limits of PBH abundance $f_{PBH}$. Using 205.4 kg$\cdot$day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory, we exclude the $χ$--electron ($χ$--$e$) elastic-scattering cross section $σ_{χe} \sim 5\times10^{-29}$ cm$^2$ for $χ$ with a mass $m_χ\lesssim$ 0.1 keV from our results. With the higher radiation background but lower energy threshold (160 eV), CDEX-10 fill a part of the gap in the previous work. If ($m_χ$, $σ_{χe}$) can be determined in the future, DD experiments are expected to impose strong constraints on $f_{PBH}$ for large $M_{PBH}$s.
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Submitted 22 September, 2024; v1 submitted 29 March, 2024;
originally announced March 2024.
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Performance of a modular ton-scale pixel-readout liquid argon time projection chamber
Authors:
DUNE Collaboration,
A. Abed Abud,
B. Abi,
R. Acciarri,
M. A. Acero,
M. R. Adames,
G. Adamov,
M. Adamowski,
D. Adams,
M. Adinolfi,
C. Adriano,
A. Aduszkiewicz,
J. Aguilar,
B. Aimard,
F. Akbar,
K. Allison,
S. Alonso Monsalve,
M. Alrashed,
A. Alton,
R. Alvarez,
T. Alves,
H. Amar,
P. Amedo,
J. Anderson,
D. A. Andrade
, et al. (1340 additional authors not shown)
Abstract:
The Module-0 Demonstrator is a single-phase 600 kg liquid argon time projection chamber operated as a prototype for the DUNE liquid argon near detector. Based on the ArgonCube design concept, Module-0 features a novel 80k-channel pixelated charge readout and advanced high-coverage photon detection system. In this paper, we present an analysis of an eight-day data set consisting of 25 million cosmi…
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The Module-0 Demonstrator is a single-phase 600 kg liquid argon time projection chamber operated as a prototype for the DUNE liquid argon near detector. Based on the ArgonCube design concept, Module-0 features a novel 80k-channel pixelated charge readout and advanced high-coverage photon detection system. In this paper, we present an analysis of an eight-day data set consisting of 25 million cosmic ray events collected in the spring of 2021. We use this sample to demonstrate the imaging performance of the charge and light readout systems as well as the signal correlations between the two. We also report argon purity and detector uniformity measurements, and provide comparisons to detector simulations.
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Submitted 5 March, 2024;
originally announced March 2024.