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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 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 (down) IFIC @ pastor @ Serial 5489  
Permanent link to this record
 

 
Author AGATA Collaboration (Valiente-Dobon, J.J. et al); Perez-Vidal, R.M.; Blasco Miquel, J.; Civera, J.V.; Gadea, A. doi  openurl
  Title Conceptual design of the AGATA 2 pi array at LNL Type Journal Article
  Year 2023 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 1049 Issue Pages 168040 - 14pp  
  Keywords AGATA spectrometer; LNL facility; gamma-ray tracking; Pulse shape analysis; PRISMA spectrometer; EUCLIDES detector; DANTE detector; TRACE detector; Plunger device  
  Abstract The Advanced GAmma Tracking Array (AGATA) has been installed at Laboratori Nazionali di Legnaro (LNL), Italy. In this installation, AGATA will consist, at the beginning, of 13 AGATA triple clusters (ATCs) with an angular coverage of 1n,and progressively the number of ATCs will increase up to a 2 pi angular coverage. This setup will exploit both stable and radioactive ion beams delivered by the Tandem-PIAVE-ALPI accelerator complex and the SPES facility. The new implementation of AGATA at LNL will be used in two different configurations, firstly one coupled to the PRISMA large-acceptance magnetic spectrometer and lately a second one at Zero Degrees, along the beam line. These two configurations will allow us to cover a broad physics program, using different reaction mechanisms, such as Coulomb excitation, fusion-evaporation, transfer and fission at energies close to the Coulomb barrier. These setups have been designed to be coupled with a large variety of complementary detectors such as charged particle detectors, neutron detectors, heavy-ion detectors, high-energy gamma-ray arrays, cryogenic and gasjet targets and the plunger device for lifetime measurements. We present in this paper the conceptual design, characteristics and performance figures of this implementation of AGATA at LNL.  
  Address [Valiente-Dobon, J. J.; Goasduff, A.; Angelini, F.; Balogh, M.; Brugnara, D.; Cocconi, P.; Cogo, A.; Collado, J.; Ertoprak, A.; Galtarossa, F.; Gambalonga, A.; Gongora Servin, B.; Gottardo, A.; Gozzelino, A.; Gulmini, M.; Marchi, T.; Modanese, P.; Napoli, D. R.; Pellumaj, J.; Perez-Vidal, R. M.; Pilotto, E.; Raniero, W.; Rosso, D.; Scarpa, D.; Sedlak, M.; Toniolo, N.; Volpe, V.; Zago, L.; Zanon, I.; Allegrini, M. L.; Benini, D.; Biasotto, M.; Corradi, L.; De Angelis, G.; De Ruvo, L.; Fantinel, S.; Fioretto, E.; Minarello, A.; Stefanini, A. M.] INFN, Lab Nazl Legnaro, Legnaro, Italy, Email: valiente@lnl.infn.it  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001020811800001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ pastor @ Serial 5590  
Permanent link to this record
 

 
Author Pasqualato, G. et al; Gadea, A.; Jurado, M. doi  openurl
  Title An alternative viewpoint on the nuclear structure towards 100Sn: Lifetime measurements in 105Sn Type Journal Article
  Year 2023 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 845 Issue Pages 138148 - 7pp  
  Keywords Nuclear structure; gamma-ray spectroscopy; Transition probabilities; Neutron-deficient isotopes; Odd-mass nuclei; Lifetime measurements  
  Abstract This work aims at presenting an alternative approach to the long standing problem of the B(E2) values in Sn isotopes in the vicinity of the N=Z double-magic nucleus Sn-100, until now predominantly measured with relativistic and intermediate-energy Coulomb excitation reactions. The direct measurement of the lifetime of low-lying excited states in odd-even Sn isotopes provides a new and precise guidance for the theoretical description of the nuclear structure in this region. Lifetime measurements have been performed in Sn-105 for the first time with the coincidence Recoil Distance Doppler Shift technique. The lifetime results for the 7/2(1)(+) first excited state and the 11/2(1)(+) state, 2(+)(Sn-104) circle times nu 1g(7/2) multiplet member, are discussed in comparison with state-of-the-art shell model and mean field calculations, highlighting the crucial contribution of proton excitation across the core of Sn-100. The reduced transition probability B(E2) of the 11/2(1)(+) core-coupled state points out an enhanced staggering with respect to the B(E2; 2(1)(+) -> 0(1)(+)) in the even-mass Sn-104 and Sn-106 isotopes.  
  Address [Pasqualato, G.; Mengonia, D.; Goasduff, A.; Lenzi, S. M.; Menegazzo, R.; Montaner-Piza, A.; Recchia, F.; Testov, D.] INFN, Sez Padova, Padua, Italy, Email: giorgia.pasqualato@IJCLAB.IN2P3.FR  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001084426400001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ pastor @ Serial 5725  
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Author AGATA Collaboration; Farnea, E.; Recchia, F.; Bazzacco, D.; Kroll, T.; Podolyak, Z.; Quintana, B.; Gadea, A. doi  openurl
  Title Conceptual design and Monte Carlo simulations of the AGATA array Type Journal Article
  Year 2010 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 621 Issue 1-3 Pages 331-343  
  Keywords Monte Carlo code; gamma-ray tracking array  
  Abstract The aim of the Advanced GAmma Tracking Array (AGATA) project is the construction of an array based on the novel concepts of pulse shape analysis and gamma-ray tracking with highly segmented Ge semiconductor detectors. The conceptual design of AGATA and its performance evaluation under different experimental conditions has required the development of a suitable Monte Carlo code. In this article, the description of the code as well as simulation results relevant for AGATA, are presented.  
  Address [Farnea, E.; Recchia, F.; Bazzacco, D.] Ist Nazl Fis Nucl, Sez Padova, Padua, Italy, Email: Enrico.Farnea@pd.infn.it  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-9002 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000281109100045 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number (down) IFIC @ elepoucu @ Serial 390  
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 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 (down) IFIC @ elepoucu @ Serial 730  
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