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Author Adhikari, R. et al; Pastor, S.; Valle, J.W.F.
Title A White Paper on keV sterile neutrino Dark Matter Type Journal Article
Year 2017 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 01 Issue (down) 1 Pages 025 - 247pp
Keywords cosmological neutrinos; dark matter experiments; dark matter theory; particle physics – cosmology connection
Abstract We present a comprehensive review of keV-scale sterile neutrino Dark Matter, collecting views and insights from all disciplines involved – cosmology, astrophysics, nuclear, and particle physics – in each case viewed from both theoretical and experimental/observational perspectives. After reviewing the role of active neutrinos in particle physics, astrophysics, and cosmology, we focus on sterile neutrinos in the context of the Dark Matter puzzle. Here, we first review the physics motivation for sterile neutrino Dark Matter, based on challenges and tensions in purely cold Dark Matter scenarios. We then round out the discussion by critically summarizing all known constraints on sterile neutrino Dark Matter arising from astrophysical observations, laboratory experiments, and theoretical considerations. In this context, we provide a balanced discourse on the possibly positive signal from X-ray observations. Another focus of the paper concerns the construction of particle physics models, aiming to explain how sterile neutrinos of keV-scale masses could arise in concrete settings beyond the Standard Model of elementary particle physics. The paper ends with an extensive review of current and future astrophysical and laboratory searches, highlighting new ideas and their experimental challenges, as well as future perspectives for the discovery of sterile neutrinos.
Address [Drewes, M.; Ibarra, A.; Lasserre, T.; Oberauer, L.; Schoenert, S.] Tech Univ Munich, Phys Dept & Excellence Cluster Univ, James Franck Str 1, D-85748 Garching, Germany, Email: marcodrewes@gmail.com;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000399409800025 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3109
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Author NEXT Collaboration (Henriques, C.A.O. et al); Alvarez, V.; Benlloch-Rodriguez, J.M.; Botas, A.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Kekic, M.; Laing, A.; Lopez-March, N.; Martinez, A.; Martinez-Lema, G.; Muñoz Vidal, J.; Musti, M.; Nebot-Guinot, M.; Novella, P.; Palmeiro, B.; Perez, J.; Querol, M.; Renner, J.; Rodriguez, J.; Romo-Luque, C.; Simon, A.; Sorel, M.; Yahlali, N.
Title Electroluminescence TPCs at the thermal diffusion limit Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue (down) 1 Pages 027 - 23pp
Keywords Dark Matter and Double Beta Decay (experiments); Photon production; Particle correlations and fluctuations; Rare decay
Abstract The NEXT experiment aims at searching for the hypothetical neutrinoless double-beta decay from the Xe-136 isotope using a high-purity xenon TPC. Efficient discrimination of the events through pattern recognition of the topology of primary ionisation tracks is a major requirement for the experiment. However, it is limited by the diffusion of electrons. It is known that the addition of a small fraction of a molecular gas to xenon reduces electron diffusion. On the other hand, the electroluminescence (EL) yield drops and the achievable energy resolution may be compromised. We have studied the effect of adding several molecular gases to xenon (CO2, CH4 and CF4) on the EL yield and energy resolution obtained in a small prototype of driftless gas proportional scintillation counter. We have compared our results on the scintillation characteristics (EL yield and energy resolution) with a microscopic simulation, obtaining the diffusion coefficients in those conditions as well. Accordingly, electron diffusion may be reduced from about 10 for pure xenon down to 2.5 using additive concentrations of about 0.05%, 0.2% and 0.02% for CO2, CH4 and CF4, respectively. Our results show that CF4 admixtures present the highest EL yield in those conditions, but very poor energy resolution as a result of huge fluctuations observed in the EL formation. CH4 presents the best energy resolution despite the EL yield being the lowest. The results obtained with xenon admixtures are extrapolated to the operational conditions of the NEXT-100 TPC. CO2 and CH4 show potential as molecular additives in a large xenon TPC. While CO2 has some operational constraints, making it difficult to be used in a large TPC, CH4 shows the best performance and stability as molecular additive to be used in the NEXT-100 TPC, with an extrapolated energy resolution of 0.4% at 2.45 MeV for concentrations below 0.4%, which is only slightly worse than the one obtained for pure xenon. We demonstrate the possibility to have an electroluminescence TPC operating very close to the thermal diffusion limit without jeopardizing the TPC performance, if CO2 or CH4 are chosen as additives.
Address [Henriques, C. A. O.; Monteiro, C. M. B.; Freitas, E. D. C.; Mano, R. D. P.; Jorge, M. R.; Fernandes, A. F. M.; Fernandes, L. M. P.; dos Santos, J. M. F.] Univ Coimbra, Phys Dept, LIBPhys, Rua Larga, P-3004516 Coimbra, Portugal, Email: pancho@gian.fis.uc.pt
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000455157300002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3873
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Author Beacham, J. et al; Martinez-Vidal, F.
Title Physics beyond colliders at CERN: beyond the Standard Model working group report Type Journal Article
Year 2020 Publication Journal of Physics G Abbreviated Journal J. Phys. G
Volume 47 Issue (down) 1 Pages 010501 - 114pp
Keywords beyond standard Model; dark matter; dark sector; axions; particle physics; accelerators
Abstract The Physics Beyond Colliders initiative is an exploratory study aimed at exploiting the full scientific potential of the CERN's accelerator complex and scientific infrastructures through projects complementary to the LHC and other possible future colliders. These projects will target fundamental physics questions in modern particle physics. This document presents the status of the proposals presented in the framework of the Beyond Standard Model physics working group, and explore their physics reach and the impact that CERN could have in the next 10-20 years on the international landscape.
Address [Beacham, J.] Duke Univ, Durham, NC 27708 USA, Email: Gaia.Lanfranchi@lnf.infn.it
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0954-3899 ISBN Medium
Area Expedition Conference
Notes WOS:000521343200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4341
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Author Villanueva-Domingo, P.; Villaescusa-Navarro, F.
Title Removing Astrophysics in 21 cm Maps with Neural Networks Type Journal Article
Year 2021 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.
Volume 907 Issue (down) 1 Pages 44 - 14pp
Keywords Cosmology; Cold dark matter; Dark matter; Dark matter distribution; H I line emission; Intergalactic medium; Cosmological evolution; Convolutional neural networks; Large-scale structure of the universe
Abstract Measuring temperature fluctuations in the 21 cm signal from the epoch of reionization and the cosmic dawn is one of the most promising ways to study the universe at high redshifts. Unfortunately, the 21 cm signal is affected by both cosmology and astrophysics processes in a nontrivial manner. We run a suite of 1000 numerical simulations with different values of the main astrophysical parameters. From these simulations we produce tens of thousands of 21 cm maps at redshifts 10 <= z <= 20. We train a convolutional neural network to remove the effects of astrophysics from the 21 cm maps and output maps of the underlying matter field. We show that our model is able to generate 2D matter fields not only that resemble the true ones visually but whose statistical properties agree with the true ones within a few percent down to scales 2 Mpc(-1). We demonstrate that our neural network retains astrophysical information that can be used to constrain the value of the astrophysical parameters. Finally, we use saliency maps to try to understand which features of the 21 cm maps the network is using in order to determine the value of the astrophysical parameters.
Address [Villanueva-Domingo, Pablo] Univ Valencia, Inst Fis Corpuscular IFIC, CSIC, Apartado Correos 22085, E-46071 Valencia, Spain, Email: Pablo.Villanueva@ific.uv.es;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-637x ISBN Medium
Area Expedition Conference
Notes WOS:000612333400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4698
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Author NEXT Collaboration (Kekic, M. et al); Benlloch-Rodriguez, J.M.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Lopez-March, N.; Martin-Albo, J.; Martinez, A.; Martinez-Lema, G.; Martinez-Vara, M.; Muñoz Vidal, J.; Novella, P.; Palmeiro, B.; Querol, M.; Renner, J.; Romo-Luque, C.; Sorel, M.; Uson, A.; Yahlali, N.
Title Demonstration of background rejection using deep convolutional neural networks in the NEXT experiment Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue (down) 1 Pages 189 - 22pp
Keywords Dark Matter and Double Beta Decay (experiments)
Abstract Convolutional neural networks (CNNs) are widely used state-of-the-art computer vision tools that are becoming increasingly popular in high-energy physics. In this paper, we attempt to understand the potential of CNNs for event classification in the NEXT experiment, which will search for neutrinoless double-beta decay in Xe-136. To do so, we demonstrate the usage of CNNs for the identification of electron-positron pair production events, which exhibit a topology similar to that of a neutrinoless double-beta decay event. These events were produced in the NEXT-White high-pressure xenon TPC using 2.6 MeV gamma rays from a Th-228 calibration source. We train a network on Monte Carlo-simulated events and show that, by applying on-the-fly data augmentation, the network can be made robust against differences between simulation and data. The use of CNNs offers significant improvement in signal efficiency and background rejection when compared to previous non-CNN-based analyses.
Address [Hauptman, J.; Nygren, D. R.] Iowa State Univ, Dept Phys & Astron, 12 Phys Hall, Ames, IA 50011 USA, Email: marija.kekic@usc.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000616730800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4729
Permanent link to this record