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Author Gammaldi, V.; Zaldivar, B.; Sanchez-Conde, M.A.; Coronado-Blazquez, J. url  doi
openurl 
  Title A search for dark matter among Fermi-LAT unidentified sources with systematic features in machine learning Type Journal Article
  Year 2023 Publication (down) Monthly Notices of the Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.  
  Volume 520 Issue 1 Pages 1348-1361  
  Keywords astroparticle physics – methods; data analysis – methods; observational – methods; statistical – dark matter – gamma-rays; general  
  Abstract Around one-third of the point-like sources in the Fermi-LAT catalogues remain as unidentified sources (unIDs) today. Indeed, these unIDs lack a clear, univocal association with a known astrophysical source. If dark matter (DM) is composed of weakly interacting massive particles (WIMPs), there is the exciting possibility that some of these unIDs may actually be DM sources, emitting gamma-rays from WIMPs annihilation. We propose a new approach to solve the standard, machine learning (ML) binary classification problem of disentangling prospective DM sources (simulated data) from astrophysical sources (observed data) among the unIDs of the 4FGL Fermi-LAT catalogue. We artificially build two systematic features for the DM data which are originally inherent to observed data: the detection significance and the uncertainty on the spectral curvature. We do it by sampling from the observed population of unIDs, assuming that the DM distributions would, if any, follow the latter. We consider different ML models: Logistic Regression, Neural Network (NN), Naive Bayes, and Gaussian Process, out of which the best, in terms of classification accuracy, is the NN, achieving around 93 . 3 per cent +/- 0 . 7 per cent performance. Other ML evaluation parameters, such as the True Ne gativ e and True Positive rates, are discussed in our work. Applying the NN to the unIDs sample, we find that the de generac y between some astrophysical and DM sources can be partially solved within this methodology. None the less, we conclude that there are no DM source candidates among the pool of 4FGL Fermi-LAT unIDs.  
  Address [Gammaldi, V; Sanchez-Conde, M. A.; Coronado-Blazquez, J.] Univ Autonoma Madrid, Departamentode Fis Teor, E-28049 Madrid, Spain, Email: viviana.gammaldi@uam.es;  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000937053400014 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 5489  
Permanent link to this record
 

 
Author Aggarwal, N. et al; Figueroa, D.G. url  doi
openurl 
  Title Challenges and opportunities of gravitational-wave searches at MHz to GHz frequencies Type Journal Article
  Year 2021 Publication (down) Living Reviews in Relativity Abbreviated Journal Living Rev. Relativ.  
  Volume 24 Issue 1 Pages 4 - 74pp  
  Keywords Ultra-high-frequency gravitational waves; Cosmological gravitational waves; Gravitational wave detectors; Fundamental physics with gavitational waves  
  Abstract The first direct measurement of gravitational waves by the LIGO and Virgo collaborations has opened up new avenues to explore our Universe. This white paper outlines the challenges and gains expected in gravitational-wave searches at frequencies above the LIGO/Virgo band, with a particular focus on Ultra High-Frequency Gravitational Waves (UHF-GWs), covering the MHz to GHz range. The absence of known astrophysical sources in this frequency range provides a unique opportunity to discover physics beyond the Standard Model operating both in the early and late Universe, and we highlight some of the most promising gravitational sources. We review several detector concepts that have been proposed to take up this challenge, and compare their expected sensitivity with the signal strength predicted in various models. This report is the summary of the workshop “Challenges and opportunities of high-frequency gravitational wave detection” held at ICTP Trieste, Italy in October 2019, that set up the stage for the recently launched Ultra-High-Frequency Gravitational Wave (UHF-GW) initiative.  
  Address [Aggarwal, Nancy] Northwestern Univ, Dept Phys & Astron, Ctr Interdisciplinary Explorat & Res Astrophys CI, Ctr Fundamental Phys, Evanston, IL 60208 USA, Email: nancy.aggarwal@northwestern.edu;  
  Corporate Author Thesis  
  Publisher Springer Int Publ Ag Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2367-3613 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000727359500002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5074  
Permanent link to this record
 

 
Author Tain, J.L. et al; Algora, A.; Estevez, E.; Rubio, B.; Valencia, E.; Jordan, D. doi  openurl
  Title Beta Decay Studies of Neutron Rich Nuclei Using Total Absorption Gamma-ray Spectroscopy and Delayed Neutron Measurements Type Journal Article
  Year 2011 Publication (down) Journal of the Korean Physical Society Abbreviated Journal J. Korean Phys. Soc.  
  Volume 59 Issue 2 Pages 1499-1502  
  Keywords Beta decay; Delayed neutron emission; Total absorption gamma-ray spectroscopy; Neutron detectors; Nuclear technology; Nuclear astrophysics  
  Abstract A complete characterisation of the beta-decay of neutron-rich nuclei can be obtained from the measurement of beta-delayed gamma rays and, whenever the process is energetically possible, beta-delayed neutrons. The accurate determination of the beta-intensity distribution and the beta-delayed neutron emission probability is of great relevance in the fields of reactor technology and nuclear astrophysics. A programme for combined measurements using the total absorption gamma-ray spectroscopy technique and both neutron counters and neutron time-of-flight spectrometers is presented.  
  Address [Tain, JL; Algora, A; Estevez, E; Rubio, B; Valencia, E; Jordan, D] Univ Valencia, CSIC, Inst Fis Corpuscular, Valencia 46071, Spain, Email: tain@ific.uv.es  
  Corporate Author Thesis  
  Publisher Korean Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0374-4884 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000294080700010 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 730  
Permanent link to this record
 

 
Author n_TOF Collaboration (Giubrone, G. et al); Tain, J.L. doi  openurl
  Title The Role of Fe and Ni for S-process Nucleosynthesis and Innovative Nuclear Technologies Type Journal Article
  Year 2011 Publication (down) Journal of the Korean Physical Society Abbreviated Journal J. Korean Phys. Soc.  
  Volume 59 Issue 2 Pages 2106-2109  
  Keywords Neutron capture cross sections; Neutron time of flight facility; C(6)D(6) detectors; Pulse height weighting technique; Nuclear astrophysics; Advanced nuclear systems  
  Abstract The accurate measurement of neutron capture cross sections of all Fe and Ni isotopes is important for disentangling the contribution of the s-process and the r-process to the stellar nucleosynthesis of elements in the mass range 60 < A < 120. At the same time, Fe and Ni are important components of structural materials and improved neutron cross section data is relevant in the design of new nuclear systems. With the aim of obtaining improved capture data on all stable iron and nickel isotopes, a program of measurements has been launched at the CERN Neutron Time of Flight Facility n_TOF.  
  Address [Giubrone, G; Tain, JL] Univ Valencia, Inst Fis Corpuscular, CSIC, E-46003 Valencia, Spain, Email: tain@ific.uv.es  
  Corporate Author Thesis  
  Publisher Korean Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0374-4884 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000294080700158 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 743  
Permanent link to this record
 

 
Author KM3NeT Collaboration (Adrian-Martinez, S. et al); Barrios-Marti, J.; Calvo Diaz-Aldagalan, D.; Hernandez-Rey, J.J.; Illuminati, G.; Lotze, M.; Olcina, I.; Real, D.; Sanchez Garcia, A.; Tönnis, C.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title Letter of intent for KM3NeT 2.0 Type Journal Article
  Year 2016 Publication (down) Journal of Physics G Abbreviated Journal J. Phys. G  
  Volume 43 Issue 8 Pages 084001 - 130pp  
  Keywords neutrino astronomy; neutrino physics; deep sea neutrino telescope; neutrino mass hierarchy  
  Abstract The main objectives of the KM3NeT Collaboration are (i) the discovery and subsequent observation of high-energy neutrino sources in the Universe and (ii) the determination of the mass hierarchy of neutrinos. These objectives are strongly motivated by two recent important discoveries, namely: (1) the high-energy astrophysical neutrino signal reported by IceCube and (2) the sizable contribution of electron neutrinos to the third neutrino mass eigenstate as reported by Daya Bay, Reno and others. To meet these objectives, the KM3NeT Collaboration plans to build a new Research Infrastructure consisting of a network of deep-sea neutrino telescopes in the Mediterranean Sea. A phased and distributed implementation is pursued which maximises the access to regional funds, the availability of human resources and the synergistic opportunities for the Earth and sea sciences community. Three suitable deep-sea sites are selected, namely off-shore Toulon (France), Capo Passero (Sicily, Italy) and Pylos (Peloponnese, Greece). The infrastructure will consist of three so-called building blocks. A building block comprises 115 strings, each string comprises 18 optical modules and each optical module comprises 31 photo-multiplier tubes. Each building block thus constitutes a three-dimensional array of photo sensors that can be used to detect the Cherenkov light produced by relativistic particles emerging from neutrino interactions. Two building blocks will be sparsely configured to fully explore the IceCube signal with similar instrumented volume, different methodology, improved resolution and complementary field of view, including the galactic plane. One building block will be densely configured to precisely measure atmospheric neutrino oscillations.  
  Address [Adrian-Martinez, S.; Ardid, M.; Llorens Alvarez, C. D.; Martinez-Mora, J. A.; Saldana, M.] Univ Politecn Valencia, Inst Invest Gest Integrada Zonas Costeras, C Paranimf 1, E-46730 Gandia, Spain, Email: brunner@cppm.in2p3.fr;  
  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:000381686700001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2773  
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