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Monte Carlo method for constructing confidence intervals with unconstrained and constrained nuisance parameters in the NOvA experiment
Authors:
M. A. Acero,
B. Acharya,
P. Adamson,
L. Aliaga,
N. Anfimov,
A. Antoshkin,
E. Arrieta-Diaz,
L. Asquith,
A. Aurisano,
A. Back,
C. Backhouse,
M. Baird,
N. Balashov,
P. Baldi,
B. A. Bambah,
S. Bashar,
A. Bat,
K. Bays,
R. Bernstein,
V. Bhatnagar,
D. Bhattarai,
B. Bhuyan,
J. Bian,
A. C. Booth,
R. Bowles
, et al. (196 additional authors not shown)
Abstract:
Measuring observables to constrain models using maximum-likelihood estimation is fundamental to many physics experiments. Wilks' theorem provides a simple way to construct confidence intervals on model parameters, but it only applies under certain conditions. These conditions, such as nested hypotheses and unbounded parameters, are often violated in neutrino oscillation measurements and other expe…
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Measuring observables to constrain models using maximum-likelihood estimation is fundamental to many physics experiments. Wilks' theorem provides a simple way to construct confidence intervals on model parameters, but it only applies under certain conditions. These conditions, such as nested hypotheses and unbounded parameters, are often violated in neutrino oscillation measurements and other experimental scenarios. Monte Carlo methods can address these issues, albeit at increased computational cost. In the presence of nuisance parameters, however, the best way to implement a Monte Carlo method is ambiguous. This paper documents the method selected by the NOvA experiment, the profile construction. It presents the toy studies that informed the choice of method, details of its implementation, and tests performed to validate it. It also includes some practical considerations which may be of use to others choosing to use the profile construction.
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Submitted 24 January, 2025; v1 submitted 28 July, 2022;
originally announced July 2022.
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Search for Slow Magnetic Monopoles with the NOvA Detector on the Surface
Authors:
NOvA Collaboration,
M. A. Acero,
P. Adamson,
L. Aliaga,
T. Alion,
V. Allakhverdian,
N. Anfimov,
A. Antoshkin,
E. Arrieta-Diaz,
L. Asquith,
A. Aurisano,
A. Back,
C. Backhouse,
M. Baird,
N. Balashov,
P. Baldi,
B. A. Bambah,
S. Bashar,
K. Bays,
S. Bending,
R. Bernstein,
V. Bhatnagar,
B. Bhuyan,
J. Bian,
J. Blair
, et al. (174 additional authors not shown)
Abstract:
We report a search for a magnetic monopole component of the cosmic-ray flux in a 95-day exposure of the NOvA experiment's Far Detector, a 14 kt segmented liquid scintillator detector designed primarily to observe GeV-scale electron neutrinos. No events consistent with monopoles were observed, setting an upper limit on the flux of $2\times 10^{-14} \mathrm{cm^{-2}s^{-1}sr^{-1}}$ at 90% C.L. for mon…
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We report a search for a magnetic monopole component of the cosmic-ray flux in a 95-day exposure of the NOvA experiment's Far Detector, a 14 kt segmented liquid scintillator detector designed primarily to observe GeV-scale electron neutrinos. No events consistent with monopoles were observed, setting an upper limit on the flux of $2\times 10^{-14} \mathrm{cm^{-2}s^{-1}sr^{-1}}$ at 90% C.L. for monopole speed $6\times 10^{-4} < β< 5\times 10^{-3}$ and mass greater than $5\times 10^{8}$ GeV. Because of NOvA's small overburden of 3 meters-water equivalent, this constraint covers a previously unexplored low-mass region.
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Submitted 5 January, 2021; v1 submitted 10 September, 2020;
originally announced September 2020.
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Supernova neutrino detection in NOvA
Authors:
NOvA Collaboration,
M. A. Acero,
P. Adamson,
G. Agam,
L. Aliaga,
T. Alion,
V. Allakhverdian,
N. Anfimov,
A. Antoshkin,
E. Arrieta-Diaz,
L. Asquith,
A. Aurisano,
A. Back,
C. Backhouse,
M. Baird,
N. Balashov,
P. Baldi,
B. A. Bambah,
S. Bashar,
K. Bays,
S. Bending,
R. Bernstein,
V. Bhatnagar,
B. Bhuyan,
J. Bian
, et al. (177 additional authors not shown)
Abstract:
The NOvA long-baseline neutrino experiment uses a pair of large, segmented, liquid-scintillator calorimeters to study neutrino oscillations, using GeV-scale neutrinos from the Fermilab NuMI beam. These detectors are also sensitive to the flux of neutrinos which are emitted during a core-collapse supernova through inverse beta decay interactions on carbon at energies of…
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The NOvA long-baseline neutrino experiment uses a pair of large, segmented, liquid-scintillator calorimeters to study neutrino oscillations, using GeV-scale neutrinos from the Fermilab NuMI beam. These detectors are also sensitive to the flux of neutrinos which are emitted during a core-collapse supernova through inverse beta decay interactions on carbon at energies of $\mathcal{O}(10~\text{MeV})$. This signature provides a means to study the dominant mode of energy release for a core-collapse supernova occurring in our galaxy. We describe the data-driven software trigger system developed and employed by the NOvA experiment to identify and record neutrino data from nearby galactic supernovae. This technique has been used by NOvA to self-trigger on potential core-collapse supernovae in our galaxy, with an estimated sensitivity reaching out to 10~kpc distance while achieving a detection efficiency of 23\% to 49\% for supernovae from progenitor stars with masses of 9.6M$_\odot$ to 27M$_\odot$, respectively.
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Submitted 29 July, 2020; v1 submitted 14 May, 2020;
originally announced May 2020.
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Observation of seasonal variation of atmospheric multiple-muon events in the NOvA Near Detector
Authors:
M. A. Acero,
P. Adamson,
L. Aliaga,
T. Alion,
V. Allakhverdian,
S. Altakarli,
N. Anmov,
A. Antoshkin,
A. Aurisano,
A. Back,
C. Backhouse,
M. Baird,
N. Balashov,
P. Baldi,
B. A. Bambah,
S. Bashar,
K. Bays,
S. Bending,
R. Bernstein,
V. Bhatnagar,
B. Bhuyan,
J. Bian,
J. Blair,
A. C. Booth,
P. Bour
, et al. (166 additional authors not shown)
Abstract:
Using two years of data from the NOvA Near Detector at Fermilab, we report a seasonal variation of cosmic ray induced multiple-muon event rates which has an opposite phase to the seasonal variation in the atmospheric temperature. The strength of the seasonal multipl$ increase as a function of the muon multiplicity. However, no significant dependence of the strength of the seasonal variation of the…
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Using two years of data from the NOvA Near Detector at Fermilab, we report a seasonal variation of cosmic ray induced multiple-muon event rates which has an opposite phase to the seasonal variation in the atmospheric temperature. The strength of the seasonal multipl$ increase as a function of the muon multiplicity. However, no significant dependence of the strength of the seasonal variation of the multiple-muon variation is seen as a function of the muon zenith angle, or the spatial or angular separation between the correlated muons.
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Submitted 8 July, 2019; v1 submitted 29 April, 2019;
originally announced April 2019.
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Neutrino Flux Predictions for the NuMI Beam
Authors:
MINERvA Collaboration,
L. Aliaga,
M. Kordosky,
T. Golan,
O. Altinok,
L. Bellantoni,
A. Bercellie,
M. Betancourt,
A. Bravar,
H. Budd,
M. F. Carneiro,
G. A. Diaz,
E. Endress,
J. Felix,
L. Fields,
R. Fine,
A. M. Gago,
R. Galindo,
H. Gallagher,
R. Gran,
D. A. Harris,
A. Higuera,
K. Hurtado,
M. Kiveni,
J. Kleykamp
, et al. (36 additional authors not shown)
Abstract:
Knowledge of the neutrino flux produced by the Neutrinos at the Main Injector (NuMI) beamline is essential to the neutrino oscillation and neutrino interaction measurements of the MINERvA, MINOS+, NOvA and MicroBooNE experiments at Fermi National Accelerator Laboratory. We have produced a flux prediction which uses all available and relevant hadron production data, incorporating measurements of pa…
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Knowledge of the neutrino flux produced by the Neutrinos at the Main Injector (NuMI) beamline is essential to the neutrino oscillation and neutrino interaction measurements of the MINERvA, MINOS+, NOvA and MicroBooNE experiments at Fermi National Accelerator Laboratory. We have produced a flux prediction which uses all available and relevant hadron production data, incorporating measurements of particle production off of thin targets as well as measurements of particle yields from a spare NuMI target exposed to a 120 GeV proton beam. The result is the most precise flux prediction achieved for a neutrino beam in the one to tens of GeV energy region. We have also compared the prediction to in situ measurements of the neutrino flux and find good agreement.
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Submitted 11 July, 2016; v1 submitted 3 July, 2016;
originally announced July 2016.
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Measurement of $K^{+}$ production in charged-current $ν_μ$ interactions
Authors:
C. M. Marshall,
L. Aliaga,
O. Altinok,
L. Bellantoni,
A. Bercellie,
M. Betancourt,
A. Bodek,
A. Bravar,
H. Budd,
T. Cai,
M. F. Carneiro,
J. Chvojka,
H. da Motta,
J. Devan,
S. A. Dytman,
G. A. Díaz,
B. Eberly,
E. Endress,
J. Felix,
L. Fields,
A. Filkins,
R. Fine,
A. M. Gago,
R. Galindo,
H. Gallagher
, et al. (57 additional authors not shown)
Abstract:
Production of K^{+} mesons in charged-current ν_μ interactions on plastic scintillator (CH) is measured using MINERvA exposed to the low-energy NuMI beam at Fermilab. Timing information is used to isolate a sample of 885 charged-current events containing a stopping K^{+} which decays at rest. The differential cross section in K^{+} kinetic energy, dσ/dT_{K}, is observed to be relatively flat betwe…
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Production of K^{+} mesons in charged-current ν_μ interactions on plastic scintillator (CH) is measured using MINERvA exposed to the low-energy NuMI beam at Fermilab. Timing information is used to isolate a sample of 885 charged-current events containing a stopping K^{+} which decays at rest. The differential cross section in K^{+} kinetic energy, dσ/dT_{K}, is observed to be relatively flat between 0 and 500 MeV. Its shape is in good agreement with the prediction by the \textsc{genie} neutrino event generator when final-state interactions are included, however the data rate is lower than the prediction by 15\%.
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Submitted 25 July, 2016; v1 submitted 13 April, 2016;
originally announced April 2016.
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Evidence for neutral-current diffractive neutral pion production from hydrogen in neutrino interactions on hydrocarbon
Authors:
MINERvA Collaboration,
J. Wolcott,
L. Aliaga,
O. Altinok,
A. Bercellie,
M. Betancourt,
A. Bodek,
A. Bravar,
H. Budd,
T. Cai,
M. F. Carneiro,
J. Chvojka,
H. da Motta,
J. Devan,
S. A. Dytman,
G. A. Díaz,
B. Eberly,
E. Endress,
J. Felix,
L. Fields,
R. Fine,
R. Galindo,
H. Gallagher,
T. Golan,
R. Gran
, et al. (46 additional authors not shown)
Abstract:
The MINERvA experiment observes an excess of events containing electromagnetic showers relative to the expectation from Monte Carlo simulations in neutral-current neutrino interactions with mean beam energy of 4.5 GeV on a hydrocarbon target. The excess is characterized and found to be consistent with neutral-current neutral pion production with a broad energy distribution peaking at 7 GeV and a t…
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The MINERvA experiment observes an excess of events containing electromagnetic showers relative to the expectation from Monte Carlo simulations in neutral-current neutrino interactions with mean beam energy of 4.5 GeV on a hydrocarbon target. The excess is characterized and found to be consistent with neutral-current neutral pion production with a broad energy distribution peaking at 7 GeV and a total cross section of 0.26 +- 0.02 (stat) +- 0.08 (sys) x 10^{-39} cm^{2}. The angular distribution, electromagnetic shower energy, and spatial distribution of the energy depositions of the excess are consistent with expectations from neutrino neutral-current diffractive neutral pion production from hydrogen in the hydrocarbon target. These data comprise the first direct experimental observation and constraint for a reaction that poses an important background process in neutrino oscillation experiments searching for muon neutrino to electron neutrino oscillations.
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Submitted 28 July, 2016; v1 submitted 6 April, 2016;
originally announced April 2016.
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Measurement of Neutrino Flux from Neutrino-Electron Elastic Scattering
Authors:
MINERvA Collaboration,
J. Park,
L. Aliaga,
O. Altinok,
L. Bellantoni,
A. Bercellie,
M. Betancourt,
A. Bodek,
A. Bravar,
H. Budd,
T. Cai,
M. F. Carneiro,
M. E. Christy,
J. Chvojka,
H. da Motta,
S. A. Dytman,
G. A. Diaz,
B. Eberly,
J. Felix,
L. Fields,
R. Fine,
A. M. Gago,
R. Galindo,
A. Ghosh,
T. Golan
, et al. (44 additional authors not shown)
Abstract:
Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently a measurement of this process in an accelerator-based $ν_μ$ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to $\sim$ 10% due to uncertainties in hadron production and focusing. We have iso…
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Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently a measurement of this process in an accelerator-based $ν_μ$ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to $\sim$ 10% due to uncertainties in hadron production and focusing. We have isolated a sample of 135 $\pm$ 17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI $ν_μ$ flux from 9% to 6%. Our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies.
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Submitted 15 June, 2016; v1 submitted 23 December, 2015;
originally announced December 2015.
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MINERvA neutrino detector response measured with test beam data
Authors:
MINERvA Collaboration,
L. Aliaga,
O. Altinok,
C. Araujo Del Castillo,
L. Bagby,
L. Bellantoni,
W. F. Bergan,
A. Bodek,
R. Bradford,
A. Bravar,
H. Budd,
A. Butkevich,
D. A. Martinez Caicedo,
M. F. Carneiro,
M. E. Christy,
J. Chvojka,
H. da Motta,
J. Devan,
G. A. Diaz,
S. A. Dytman,
B. Eberly,
J. Felix,
L. Fields,
R. Fine,
R. Flight
, et al. (63 additional authors not shown)
Abstract:
The MINERvA collaboration operated a scaled-down replica of the solid scintillator tracking and sampling calorimeter regions of the MINERvA detector in a hadron test beam at the Fermilab Test Beam Facility. This article reports measurements with samples of protons, pions, and electrons from 0.35 to 2.0 GeV/c momentum. The calorimetric response to protons, pions, and electrons are obtained from the…
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The MINERvA collaboration operated a scaled-down replica of the solid scintillator tracking and sampling calorimeter regions of the MINERvA detector in a hadron test beam at the Fermilab Test Beam Facility. This article reports measurements with samples of protons, pions, and electrons from 0.35 to 2.0 GeV/c momentum. The calorimetric response to protons, pions, and electrons are obtained from these data. A measurement of the parameter in Birks' law and an estimate of the tracking efficiency are extracted from the proton sample. Overall the data are well described by a Geant4-based Monte Carlo simulation of the detector and particle interactions with agreements better than 4%, though some features of the data are not precisely modeled. These measurements are used to tune the MINERvA detector simulation and evaluate systematic uncertainties in support of the MINERvA neutrino cross section measurement program.
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Submitted 7 April, 2015; v1 submitted 26 January, 2015;
originally announced January 2015.
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Design, Calibration, and Performance of the MINERvA Detector
Authors:
L. Aliaga,
L. Bagby,
B. Baldin,
A. Baumbaugh,
A. Bodek,
R. Bradford,
W. K. Brooks,
D. Boehnlein,
S. Boyd,
H. Budd,
A. Butkevich,
D. A. Martinez Caicedo,
C. M. Castromonte,
M. E. Christy,
J. Chvojka,
H. da Motta,
D. S. Damiani,
I. Danko,
M. Datta,
R. DeMaat,
J. Devan,
E. Draeger,
S. A. Dytman,
G. A. Diaz,
B. Eberly
, et al. (80 additional authors not shown)
Abstract:
The MINERvA experiment is designed to perform precision studies of neutrino-nucleus scattering using $ν_μ$ and ${\barν}_μ$ neutrinos incident at 1-20 GeV in the NuMI beam at Fermilab. This article presents a detailed description of the \minerva detector and describes the {\em ex situ} and {\em in situ} techniques employed to characterize the detector and monitor its performance. The detector is co…
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The MINERvA experiment is designed to perform precision studies of neutrino-nucleus scattering using $ν_μ$ and ${\barν}_μ$ neutrinos incident at 1-20 GeV in the NuMI beam at Fermilab. This article presents a detailed description of the \minerva detector and describes the {\em ex situ} and {\em in situ} techniques employed to characterize the detector and monitor its performance. The detector is comprised of a finely-segmented scintillator-based inner tracking region surrounded by electromagnetic and hadronic sampling calorimetry. The upstream portion of the detector includes planes of graphite, iron and lead interleaved between tracking planes to facilitate the study of nuclear effects in neutrino interactions. Observations concerning the detector response over sustained periods of running are reported. The detector design and methods of operation have relevance to future neutrino experiments in which segmented scintillator tracking is utilized.
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Submitted 22 May, 2013;
originally announced May 2013.