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Author Panes, B.; Eckner, C.; Hendriks, L.; Caron, S.; Dijkstra, K.; Johannesson, G.; Ruiz de Austri, R.; Zaharijas, G. url  doi
openurl 
  Title Identification of point sources in gamma rays using U-shaped convolutional neural networks and a data challenge Type Journal Article
  Year 2021 Publication Astronomy & Astrophysics Abbreviated Journal Astron. Astrophys.  
  Volume 656 Issue (up) Pages A62 - 18pp  
  Keywords catalogs; gamma rays: general; astroparticle physics; methods: numerical; methods: data analysis; techniques: image processing  
  Abstract Context. At GeV energies, the sky is dominated by the interstellar emission from the Galaxy. With limited statistics and spatial resolution, accurately separating point sources is therefore challenging. Aims. Here we present the first application of deep learning based algorithms to automatically detect and classify point sources from gamma-ray data. For concreteness we refer to this approach as AutoSourceID. Methods. To detect point sources, we utilized U-shaped convolutional networks for image segmentation and k-means for source clustering and localization. We also explored the Centroid-Net algorithm, which is designed to find and count objects. Using two algorithms allows for a cross check of the results, while a combination of their results can be used to improve performance. The training data are based on 9.5 years of exposure from The Fermi Large Area Telescope (Fermi-LAT) and we used source properties of active galactic nuclei (AGNs) and pulsars (PSRs) from the fourth Fermi-LAT source catalog in addition to several models of background interstellar emission. The results of the localization algorithm are fed into a classification neural network that is trained to separate the three general source classes (AGNs, PSRs, and FAKE sources). Results. We compared our localization algorithms qualitatively with traditional methods and find them to have similar detection thresholds. We also demonstrate the robustness of our source localization algorithms to modifications in the interstellar emission models, which presents a clear advantage over traditional methods. The classification network is able to discriminate between the three classes with typical accuracy of similar to 70%, as long as balanced data sets are used in classification training. We published online our training data sets and analysis scripts and invite the community to join the data challenge aimed to improve the localization and classification of gamma-ray point sources.  
  Address [Panes, Boris] Pontificia Univ Catolica Chile, Ave Vicuna Mackenna 4860, Macul, Region Metropol, Chile, Email: bapanes@gmail.com  
  Corporate Author Thesis  
  Publisher Edp Sciences S A Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0004-6361 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000725877600001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5053  
Permanent link to this record
 

 
Author Tonev, D. et al; Gadea, A. doi  openurl
  Title Transition probabilities in P-31 and S-31: A test for isospin symmetry Type Journal Article
  Year 2021 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 821 Issue (up) Pages 136603 - 6pp  
  Keywords Mirror nuclei; Lifetime measurements; Transition probabilities; Isospin symmetry; Microscopic multiphonon model  
  Abstract Excited states in the mirror nuclei P-31 and S-31 were populated in the 1p and 1n exit channels of the reaction Ne-20 + C-12, at a beam energy of 33 MeV. The Ne-20 beam was delivered for the first time by the Piave-Alpi accelerator of the Laboratori Nazionali di Legnaro. Angular correlations of coincident gamma-rays and Doppler-shift attenuation lifetime measurements were performed using the multi-detector array GASP in conjunction with the EUCLIDES charged particle detector. In the observed B(E1) strengths, the isoscalar component, amounting to 24% of the isovector one, provides strong evidence for breaking of the isospin symmetry in the A = 31 mass region. Self-consistent beyond mean field calculations using Equation of Motion method based on a chiral potential and including two- and three-body forces reproduce well the experimental B(E1) strengths, reinforcing our conclusion. Coherent mixing from higher-lying states involving the Giant Isovector Monopole Resonance accounts well for the effect observed. The breaking of the isospin symmetry originates from the violation of the charge symmetry of the two- and three-body parts of the potential, only related to the Coulomb interaction.  
  Address [Tonev, D.; Goutev, N.; Pavlov, P.; Pantaleev, I. L.; Iliev, S.; Yavahchova, M. S.; Demerdjiev, A.; Dimitrov, D. T.; Geleva, E.; Laftchiev, H.] Bulgarian Acad Sci, Inst Nucl Res & Nucl Energy, BG-1784 Sofia, Bulgaria, Email: dimitar.tonev@inrne.bas.bg  
  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:000734909800003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5064  
Permanent link to this record
 

 
Author Folgado, M.G.; Sanz, V. url  doi
openurl 
  Title Exploring the political pulse of a country using data science tools Type Journal Article
  Year 2022 Publication Journal of Computational Social Science Abbreviated Journal J. Comput. Soc. Sci.  
  Volume 5 Issue (up) Pages 987-1000  
  Keywords Politics; Spain; Sentiment analysis; Artificial Intelligence; Machine learning; Neural networks; Natural Language Processing (NLP)  
  Abstract In this paper we illustrate the use of Data Science techniques to analyse complex human communication. In particular, we consider tweets from leaders of political parties as a dynamical proxy to political programmes and ideas. We also study the temporal evolution of their contents as a reaction to specific events. We analyse levels of positive and negative sentiment in the tweets using new tools adapted to social media. We also train a Fully-Connected Neural Network (FCNN) to recognise the political affiliation of a tweet. The FCNN is able to predict the origin of the tweet with a precision in the range of 71-75%, and the political leaning (left or right) with a precision of around 90%. This study is meant to be viewed as an example of how to use Twitter data and different types of Data Science tools for a political analysis.  
  Address [Folgado, Miguel G.; Sanz, Veronica] Univ Valencia, Inst Fis Corpuscular IFIC, CSIC, Valencia 46980, Spain, Email: migarfol@upvnet.upv.es;  
  Corporate Author Thesis  
  Publisher Springernature Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2432-2717 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000742263500002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5077  
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Author Asai, M.; Cortes-Giraldo, M.A.; Gimenez-Alventosa, V.; Gimenez, V.; Salvat, F. doi  openurl
  Title The PENELOPE Physics Models and Transport Mechanics. Implementation into Geant4 Type Journal Article
  Year 2021 Publication Frontiers in Physics Abbreviated Journal Front. Physics  
  Volume 9 Issue (up) Pages 738735 - 20pp  
  Keywords coupled electron-photon transport; Monte Carlo simulation; PENELOPE code system; random-hinge method; Geant4 toolkit  
  Abstract A translation of the penelope physics subroutines to C++, designed as an extension of the Geant4 toolkit, is presented. The Fortran code system penelope performs Monte Carlo simulation of coupled electron-photon transport in arbitrary materials for a wide energy range, nominally from 50 eV up to 1 GeV. Penelope implements the most reliable interaction models that are currently available, limited only by the required generality of the code. In addition, the transport of electrons and positrons is simulated by means of an elaborate class II scheme in which hard interactions (involving deflection angles or energy transfers larger than pre-defined cutoffs) are simulated from the associated restricted differential cross sections. After a brief description of the interaction models adopted for photons and electrons/positrons, we describe the details of the class-II algorithm used for tracking electrons and positrons. The C++ classes are adapted to the specific code structure of Geant4. They provide a complete description of the interactions and transport mechanics of electrons/positrons and photons in arbitrary materials, which can be activated from the G4ProcessManager to produce simulation results equivalent to those from the original penelope programs. The combined code, named PenG4, benefits from the multi-threading capabilities and advanced geometry and statistical tools of Geant4.  
  Address [Asai, Makoto] SLAC Natl Accelerator Lab, Menlo Pk, CA USA, Email: miancortes@us.es;  
  Corporate Author Thesis  
  Publisher Frontiers Media Sa Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2296-424x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000742889400001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5080  
Permanent link to this record
 

 
Author Coves, A.; Maestre, H.; Archiles, R.; Andres, M.V.; Gimeno, B. doi  openurl
  Title Surface-Impedance Formulation for Hollow-Core Waveguides Based on Subwavelength Gratings Type Journal Article
  Year 2022 Publication IEEE Access Abbreviated Journal IEEE Access  
  Volume 10 Issue (up) Pages 18843-18854  
  Keywords Electromagnetic waveguides; Optical waveguides; Planar waveguides; Gratings; Surface waves; Surface impedance; Optical surface waves; Surface impedance; hollow-core waveguide; surface-relief grating  
  Abstract A rigorous Surface Impedance (SI) formulation for planar waveguides is presented. This modal technique splits the modal analysis of the waveguide in two steps. First, we obtain the modes characteristic equations as a function of the SI and, second, we need to obtain the surface impedance values using either analytical or numerical methods. We validate the technique by comparison with well-known analytical cases: the parallel-plate waveguide with losses and the dielectric slab waveguide. Then, we analyze an optical hollow-core waveguide defined by two high-contrast subwavelength gratings validating our results by comparison with reported values. Finally, we show the potential of our formulation with the analysis of a THz hollow-core waveguide defined by two surface-relief subwavelength gratings, including material losses in our formulation.  
  Address [Coves, Angela; Maestre, Haroldo] Univ Miguel Hernandez Elche, Dept Commun Engn I3E, Elche 03202, Spain, Email: angela.coves@umh.es  
  Corporate Author Thesis  
  Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2169-3536 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000760714900001 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 5139  
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Author Hirn, J.; Garcia, J.E.; Montesinos-Navarro, A.; Sanchez-Martin, R.; Sanz, V.; Verdu, M. url  doi
openurl 
  Title A deep Generative Artificial Intelligence system to predict species coexistence patterns Type Journal Article
  Year 2022 Publication Methods in Ecology and Evolution Abbreviated Journal Methods Ecol. Evol.  
  Volume 13 Issue (up) Pages 1052-1061  
  Keywords artificial intelligence; direct interactions; generative adversarial networks; indirect interactions; species coexistence; variational AutoEncoders  
  Abstract Predicting coexistence patterns is a current challenge to understand diversity maintenance, especially in rich communities where these patterns' complexity is magnified through indirect interactions that prevent their approximation with classical experimental approaches. We explore cutting-edge Machine Learning techniques called Generative Artificial Intelligence (GenAI) to predict species coexistence patterns in vegetation patches, training generative adversarial networks (GAN) and variational AutoEncoders (VAE) that are then used to unravel some of the mechanisms behind community assemblage. The GAN accurately reproduces real patches' species composition and plant species' affinity to different soil types, and the VAE also reaches a high level of accuracy, above 99%. Using the artificially generated patches, we found that high-order interactions tend to suppress the positive effects of low-order interactions. Finally, by reconstructing successional trajectories, we could identify the pioneer species with larger potential to generate a high diversity of distinct patches in terms of species composition. Understanding the complexity of species coexistence patterns in diverse ecological communities requires new approaches beyond heuristic rules. Generative Artificial Intelligence can be a powerful tool to this end as it allows to overcome the inherent dimensionality of this challenge.  
  Address [Hirn, Johannes; Enrique Garcia, Jose; Sanz, Veronica] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Valencia, Spain, Email: miguel.verdu@ext.uv.es  
  Corporate Author Thesis  
  Publisher Wiley Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-210x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000765239700001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5155  
Permanent link to this record
 

 
Author Chiera, N.M.; Maugeri, E.A.; Danilov, I.; Balibrea-Correa, J.; Domingo-Pardo, C.; Koster, U.; Lerendegui-Marco, J.; Veicht, M.; Zivadinovic, I.; Schumann, D. doi  openurl
  Title Preparation of PbSe targets for Se-79 neutron capture cross section studies Type Journal Article
  Year 2022 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 1029 Issue (up) Pages 166443 - 7pp  
  Keywords Lead selenide; Selenium-79; Neutron capture; PbSe target; Se separation  
  Abstract A methodology for the production of PbSe targets for Se-79 neutron capture cross section studies is presented. PbSe material was synthesized by direct reaction of its constituents at high temperature, and characterized by X-ray diffraction. Thin PbSe targets, produced for cross section experiments with the surrogate reaction method, were obtained by applying a physical vapor deposition technique, and their morphology and composition were analyzed by X-ray fluorescence, Scanning Electron Microscopy, and Energy dispersive X-ray spectroscopy. (PbSe)-Se-79 targets produced for cross section measurements with the Time of Flight method were characterized by gamma-ray spectroscopy. Finally, a procedure for the recovery of Se from PbSe is suggested. The purity of the retrieved Se was determined with Inductively Coupled Plasma Optical Emission Spectroscopy.  
  Address [Chiera, Nadine M.; Maugeri, Emilio Andrea; Danilov, Ivan; Veicht, Mario; Zivadinovic, Ivan; Schumann, Dorothea] Paul Scherrer Inst, Villigen, Switzerland, Email: nadine-mariel.chiera@psi.ch  
  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:000783012200016 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 5204  
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Author Sanchis-Lozano, M.A.; Melia, F.; Lopez-Corredoira, M.; Sanchis-Gual, N. url  doi
openurl 
  Title Missing large-angle correlations versus even-odd point-parity imbalance in the cosmic microwave background Type Journal Article
  Year 2022 Publication Astronomy & Astrophysics Abbreviated Journal Astron. Astrophys.  
  Volume 660 Issue (up) Pages A121 - 10pp  
  Keywords cosmological parameters; cosmic background radiation; cosmology: observations; cosmology: theory; inflation; large-scale structure of Universe  
  Abstract Context. The existence of a maximum correlation angle (theta(max) & 60 greater than or similar to degrees) in the two-point angular temperature correlations of cosmic microwave background (CMB) radiation, measured by WMAP and Planck, stands in sharp contrast to the prediction of standard inflationary cosmology, in which the correlations should extend across the full sky (i.e., 180 degrees). The introduction of a hard lower cuto ff (k(min)) in the primordial power spectrum, however, leads naturally to the existence of theta(max). Among other cosmological anomalies detected in these data, an apparent dominance of odd-over-even parity multipoles has been seen in the angular power spectrum of the CMB. This feature, however, may simply be due to observational contamination in certain regions of the sky. Aims. In attempting to provide a more detailed assessment of whether this odd-over-even asymmetry is intrinsic to the CMB, we therefore proceed in this paper, first, to examine whether this odd-even parity imbalance also manifests itself in the angular correlation function and, second, to examine in detail the interplay between the presence of theta(max) and this observed anomaly. Methods. We employed several parity statistics and recalculated the angular correlation function for di fferent values of the cuto ff kmin in order to optimize the fit to the di fferent Planck 2018 data. Results. We find a phenomenological connection between these features in the data, concluding that both must be considered together in order to optimize the theoretical fit to the Planck 2018 data. Conclusions. This outcome is independent of whether the parity imbalance is intrinsic to the CMB, but if it is, the odd-over-even asymmetry would clearly point to the emergence of new physics.  
  Address [Sanchis-Lozano, M-A] Ctr Mixto Univ Valencia, Inst Fis Corpuscular IFIC, CSIC, Dr Moliner 50, Burjassot, Spain, Email: Miguel.Angel.Sanchis@ific.uv.es;  
  Corporate Author Thesis  
  Publisher Edp Sciences S A Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0004-6361 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000786712000002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5211  
Permanent link to this record
 

 
Author Navarro, P.; Gimeno, B.; Alvarez Melcon, A.; Arguedas Cuendis, S.; Cogollos, C.; Diaz-Morcillo, A.; Gallego, J.D.; Garcia Barcelo, J.M.; Golm, J.; Irastorza, I.G.; Lozano Guerrero, A.J.; Garay, C.P. url  doi
openurl 
  Title Wide-band full-wave electromagnetic modal analysis of the coupling between dark-matter axions and photons in microwave resonators Type Journal Article
  Year 2022 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe  
  Volume 36 Issue (up) Pages 101001 - 14pp  
  Keywords Axion detection; Axion field; Axion-photon interaction; BI-RME 3D; Broad-band analysis; Dark matter; Full wave analysis; Haloscope; Microwave resonator; Modal technique  
  Abstract The electromagnetic coupling axion-photon in a microwave cavity is revisited with the Boundary Integral-Resonant Mode Expansion (BI-RME) 3D technique. Such full-wave modal technique has been applied for the rigorous analysis of the excitation of a microwave cavity with an axion field. In this scenario, the electromagnetic field generated by the axion-photon coupling can be assumed to be driven by equivalent electrical charge and current densities. These densities have been inserted in the general BI-RME 3D equations, which express the RF electromagnetic field existing within a cavity as an integral involving the Dyadic Green's functions of the cavity (under Coulomb gauge) as well as such densities. This method is able to take into account any arbitrary spatial and temporal variation of both magnitude and phase of the axion field. Next, we have obtained a simple network driven by the axion current source, which represents the coupling between the axion field and the resonant modes of the cavity. With this approach, it is possible to calculate the extracted and dissipated RF power as a function of frequency along a broad band and without Cauchy-Lorentz approximations, obtaining the spectrum of the electromagnetic field generated in the cavity, and dealing with modes relatively close to the axion resonant mode. Moreover, with this technique we have a complete knowledge of the signal extracted from the cavity, not only in magnitude but also in phase. This can be an interesting issue for future analysis where the axion phase is an important parameter.  
  Address [Navarro, P.; Melcon, A. alvarez; Diaz-Morcillo, A.; Barcelo, J. M. Garcia; Guerrero, A. J. Lozano] Tech Univ Cartagena, Dept Informat & Commun Technol, Cartagena 30203, Spain, Email: pablonm.ct.94@gmail.com;  
  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 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000791333100001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5218  
Permanent link to this record
 

 
Author ANTARES Collaboration (Albert, A. et al); Alves, S.; Calvo, D.; Carretero, V.; Gozzini, R.; Hernandez-Rey, J.J.; Khan-Chowdhury, N.R.; Manczak, J.; Pieterse, C.; Sanchez-Losa, A.; Salesa Greus, F.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title Search for magnetic monopoles with ten years of the ANTARES neutrino telescope Type Journal Article
  Year 2022 Publication Journal of High Energy Astrophysics Abbreviated Journal J. High Energy Astrophys.  
  Volume 34 Issue (up) Pages 1-8  
  Keywords ANTARES telescope; Magnetic monopoles; Neutrino  
  Abstract This work presents a new search for magnetic monopoles using data taken with the ANTARES neutrino telescope over a period of 10 years (January 2008 to December 2017). Compared to previous ANTARES searches, this analysis uses a run-by-run simulation strategy, with a larger exposure as well as a new simulation of magnetic monopoles taking into account the Kasama, Yang and Goldhaber model for their interaction cross-section with matter. No signal compatible with the passage of relativistic magnetic monopoles is observed, and upper limits on the flux of magnetic monopoles with beta = v/c & nbsp;>=& nbsp;0.55, are presented. For ultra-relativistic magnetic monopoles the flux limit is similar to 7 x 10(-18) cm(-2) s(-1) sr(-1). (C)& nbsp;2022 Elsevier B.V. All rights reserved.  
  Address [Albert, A.; Pradier, T.] Univ Strasbourg, CNRS, UMR 7178, F-67000 Strasbourg, France, Email: boumaaza.jihad@gmail.com  
  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 2214-4048 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000791701000001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5223  
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