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Searching for Hidden Neutrons with a Reactor Neutrino Experiment: Constraints from the STEREO Experiment
Authors:
H. Almazán,
L. Bernard,
A. Blanchet,
A. Bonhomme,
C. Buck,
P. del Amo Sanchez,
I. El Atmani,
L. Labit,
J. Lamblin,
A. Letourneau,
D. Lhuillier,
M. Licciardi,
M. Lindner,
T. Materna,
O. Méplan,
H. Pessard,
G. Pignol,
J. -S. Réal,
J. -S. Ricol,
C. Roca,
R. Rogly,
T. Salagnac,
M. Sarrazin,
V. Savu,
S. Schoppmann
, et al. (3 additional authors not shown)
Abstract:
Different extensions of the standard model of particle physics, such as braneworld or mirror matter models, predict the existence of a neutron sterile state, possibly as a dark matter candidate. This Letter reports a new experimental constraint on the probability $p$ for neutron conversion into a hidden neutron, set by the STEREO experiment at the high flux reactor of the Institut Laue-Langevin. T…
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Different extensions of the standard model of particle physics, such as braneworld or mirror matter models, predict the existence of a neutron sterile state, possibly as a dark matter candidate. This Letter reports a new experimental constraint on the probability $p$ for neutron conversion into a hidden neutron, set by the STEREO experiment at the high flux reactor of the Institut Laue-Langevin. The limit is $p<3.1\times 10^{-11}$ at $95 \%$ C.L. improving the previous limit by a factor 13. This result demonstrates that short-baseline neutrino experiments can be used as competitive passing-through-walls neutron experiments to search for hidden neutrons.
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Submitted 21 January, 2022; v1 submitted 2 November, 2021;
originally announced November 2021.
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Probing neutron-hidden neutron transitions with the MURMUR experiment
Authors:
C. Stasser,
G. Terwagne,
J. Lamblin,
O. Méplan,
G. Pignol,
B. Coupé,
S. Kalcheva,
S. Van Dyck,
M. Sarrazin
Abstract:
MURMUR is a new passing-through-walls neutron experiment designed to constrain neutron/hidden neutron transitions allowed in the context of braneworld scenarios or mirror matter models. A nuclear reactor can act as a hidden neutron source, such that neutrons travel through a hidden world or sector. Hidden neutrons can propagate out of the nuclear core and far beyond the biological shielding. Howev…
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MURMUR is a new passing-through-walls neutron experiment designed to constrain neutron/hidden neutron transitions allowed in the context of braneworld scenarios or mirror matter models. A nuclear reactor can act as a hidden neutron source, such that neutrons travel through a hidden world or sector. Hidden neutrons can propagate out of the nuclear core and far beyond the biological shielding. However, hidden neutrons can weakly interact with usual matter, making possible for their detection in the context of low-noise measurements. In the present work, the novelty rests on a better background discrimination and the use of a mass of a material - here lead - able to enhance regeneration of hidden neutrons into visible ones to improve detection. The input of this new setup is studied using both modelizations and experiments, thanks to tests currently performed with the experiment at the BR2 research nuclear reactor (SCK$\cdot$CEN, Mol, Belgium). A new limit on the neutron swapping probability p has been derived thanks to the measurements taken during the BR2 Cycle 02/2019A: $p < 4.0 \ \times 10^{-10}$ at 95% CL. This constraint is better than the bound from the previous passing-through-wall neutron experiment made at ILL in 2015, despite BR2 is less efficient to generate hidden neutrons by a factor 7.4, thus raising the interest of such experiment using regenerating materials.
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Submitted 7 January, 2021; v1 submitted 22 July, 2020;
originally announced July 2020.
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Search for neutron-hidden neutron interbrane transitions with MURMUR, a low-noise neutron passing-through-walls experiment
Authors:
Coraline Stasser,
Michaël Sarrazin,
Guy Terwagne
Abstract:
Multi-braneworld universe is at the heart of many scenarios of physics beyond the Standard Model and the cosmological model $ΛCDM$. It is thus an important concern to constrain these scenarios which also allow for experiments below the GeV scale. MURMUR is a new neutron-passing-through-walls experiment designed to constrain neutron-hidden neutron transitions in the context of braneworlds scenarios…
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Multi-braneworld universe is at the heart of many scenarios of physics beyond the Standard Model and the cosmological model $ΛCDM$. It is thus an important concern to constrain these scenarios which also allow for experiments below the GeV scale. MURMUR is a new neutron-passing-through-walls experiment designed to constrain neutron-hidden neutron transitions in the context of braneworlds scenarios. As our visible universe could be a 3-brane embedded in a multidimensional bulk, adjacent hidden 3-branes are often expected. Their existence can be constrained as matter exchange between braneworlds must occur with a swapping probability $p$. A neutron $n$ can convert into a hidden neutron $n'$ when scattered by a nucleus with cross section $σ(n \to n')$ $\propto$ $σ_E (n \to n)\ p$, where $σ_E$ is the usual elastic cross-section. Hidden neutrons could therefore be generated in the moderator medium of a nuclear reactor, where high-flux neutrons undergo many elastic collisions. All the theoretical and technological keys of this experiment soon to be installed at the nuclear research reactor BR2 (SCK.CEN, Mol, Belgium) are introduced.
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Submitted 15 February, 2019; v1 submitted 30 October, 2018;
originally announced October 2018.
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Bounds on ortho-positronium and $J/ψ$-$Υ$ quarkonia invisible decays and constraints on hidden braneworlds in a $SO(3,1)$-broken 5D bulk
Authors:
Michael Sarrazin,
Coraline Stasser
Abstract:
While our visible Universe could be a 3-brane, some cosmological scenarios consider that other 3-branes could be hidden in the extra-dimensional bulk. Matter disappearance toward a hidden brane is mainly discussed for neutron - both theoretically and experimentally - but other particles are poorly studied. Recent experimental results offer new constraints on positronium or quarkonium invisible dec…
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While our visible Universe could be a 3-brane, some cosmological scenarios consider that other 3-branes could be hidden in the extra-dimensional bulk. Matter disappearance toward a hidden brane is mainly discussed for neutron - both theoretically and experimentally - but other particles are poorly studied. Recent experimental results offer new constraints on positronium or quarkonium invisible decays. In the present work, we show how a two-brane Universe allows for such invisible decays. We put this result in the context of the recent experimental data to constrain the brane energy scale $M_B$ (or effective brane thickness $M_B^{-1}$) and the interbrane distance $d$ for a relevant two-brane Universe in a $SO(3,1)$-broken 5D bulk. Quarkonia present poor bounds compared to results deduced from previous passing-through-walls-neutron experiments for which scenarios with $M_B < 2.5 \times 10^{17}$ GeV and $d > 0.5$ fm are excluded. By contrast, positronium experiments can compete with neutron experiments depending on the matter content of each brane. To constrain scenarios up to the Planck scale, positronium experiments in vacuum cavity should be able to reach $\text{Br}(\text{o-Ps} \rightarrow \text{invisible}) \approx 10^{-6}$.
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Submitted 26 February, 2020; v1 submitted 20 October, 2018;
originally announced October 2018.
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Search for passing-through-walls neutrons constrains hidden braneworlds
Authors:
Michael Sarrazin,
Guillaume Pignol,
Jacob Lamblin,
Jonhathan Pinon,
Olivier Meplan,
Guy Terwagne,
Paul-Louis Debarsy,
Fabrice Petit,
Valery V. Nesvizhevsky
Abstract:
In many theoretical frameworks our visible world is a $3$-brane, embedded in a multidimensional bulk, possibly coexisting with hidden braneworlds. Some works have also shown that matter swapping between braneworlds can occur. Here we report the results of an experiment - at the Institut Laue-Langevin (Grenoble, France) - designed to detect thermal neutron swapping to and from another braneworld, t…
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In many theoretical frameworks our visible world is a $3$-brane, embedded in a multidimensional bulk, possibly coexisting with hidden braneworlds. Some works have also shown that matter swapping between braneworlds can occur. Here we report the results of an experiment - at the Institut Laue-Langevin (Grenoble, France) - designed to detect thermal neutron swapping to and from another braneworld, thus constraining the probability $p^2$ of such an event. The limit, $p<4.6\times 10^{-10}$ at $95 \%$ C.L., is $4$ orders of magnitude better than the previous bound based on the disappearance of stored ultracold neutrons. In the simplest braneworld scenario, for two parallel Planck-scale branes separated by a distance $d$, we conclude that $d>87$ in Planck length units.
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Submitted 26 April, 2016;
originally announced April 2016.
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Probing the braneworld hypothesis with a neutron-shining-through-a-wall experiment
Authors:
Michael Sarrazin,
Guillaume Pignol,
Jacob Lamblin,
Fabrice Petit,
Guy Terwagne,
Valery V. Nesvizhevsky
Abstract:
The possibility for our visible world to be a 3-brane embedded in a multidimensional bulk is at the heart of many theoretical edifices in high-energy physics. Probing the braneworld hypothesis is thus a major experimental challenge. Following recent theoretical works showing that matter swapping between braneworlds can occur, we propose a neutron-shining-through-a-wall experiment. We first show th…
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The possibility for our visible world to be a 3-brane embedded in a multidimensional bulk is at the heart of many theoretical edifices in high-energy physics. Probing the braneworld hypothesis is thus a major experimental challenge. Following recent theoretical works showing that matter swapping between braneworlds can occur, we propose a neutron-shining-through-a-wall experiment. We first show that an intense neutron source such as a nuclear reactor core can induce a hidden neutron flux in an adjacent hidden braneworld. We then describe how a low-background detector can detect neutrons arising from the hidden world and quantify the expected sensitivity to the swapping probability. As a proof of concept, a constraint is derived from previous experiments.
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Submitted 20 April, 2015; v1 submitted 26 January, 2015;
originally announced January 2015.
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Testing baryon number conservation in braneworld models with cold neutrons
Authors:
Michael Sarrazin
Abstract:
In the context of multi-brane Universe models, matter swapping between two braneworlds is allowed leading to a baryon number violation in our visible world. An experimental framework is described to test such a phenomenology with cold neutrons thanks to a neutron-shining-through-a-wall experiment.
In the context of multi-brane Universe models, matter swapping between two braneworlds is allowed leading to a baryon number violation in our visible world. An experimental framework is described to test such a phenomenology with cold neutrons thanks to a neutron-shining-through-a-wall experiment.
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Submitted 26 October, 2013;
originally announced October 2013.
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Experimental limits on neutron disappearance into another braneworld
Authors:
Michael Sarrazin,
Guillaume Pignol,
Fabrice Petit,
Valery V. Nesvizhevsky
Abstract:
Recent theoretical works have shown that matter swapping between two parallel braneworlds could occur under the influence of magnetic vector potentials. In our visible world, galactic magnetism possibly produces a huge magnetic potential. As a consequence, this paper discusses the possibility to observe neutron disappearance into another braneworld in certain circumstances. The setup under conside…
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Recent theoretical works have shown that matter swapping between two parallel braneworlds could occur under the influence of magnetic vector potentials. In our visible world, galactic magnetism possibly produces a huge magnetic potential. As a consequence, this paper discusses the possibility to observe neutron disappearance into another braneworld in certain circumstances. The setup under consideration involves stored ultracold neutrons - in a vessel - which should exhibit a non-zero probability p to disappear into an invisible brane at each wall collision. An upper limit of p is assessed based on available experimental results. This value is then used to constrain the parameters of the theoretical model. Possible improvements of the experiments are discussed, including enhanced stimulated swapping by artificial means.
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Submitted 14 May, 2012; v1 submitted 18 January, 2012;
originally announced January 2012.