Exploració per tema "Astrofísica"

Ara es mostren els items 21-40 de 224

    • ANTARES neutrino search for time and space correlations with IceCube high-energy neutrino events 

      André, Michel; Albert, A.; Anghinolfi, Marco; Anton, Gisela (Institute of Physics (IOP), 2019-07-10)
      Article
      Accés obert
      In the past years, the IceCube Collaboration has reported in several analyses the observation of astrophysical high-energy neutrino events. Despite a compelling evidence for the first identification of a neutrino source, ...

    • ANTARES search for neutrino flares from the direction of radio-bright blazars 

      Alves Garre, Sergio; André, Michel; Anghinolfi, Marco; Anton, Gisela; Ardid Ramírez, Miguel; Aublin, J.; Belhorma, Bouchra; Bendahman, Meriem; Bertin, Vincent; Bissinger, Matthias; Boumaaza, Jihad (arXiv, 2021)
      Text en actes de congrés
      Accés obert
      In 2017, a high-energy muon neutrino detected by IceCube was found positionally coincident with the direction of a known blazar, TXS 0506+056, in a state of enhanced 훾-ray emission. Soon after, IceCube reported a compelling ...

    • ANTARES search for point sources of neutrinos using astrophysical catalogs: a likelihood analysis 

      Albert, A.; André, Michel; Anghinolfi, Marco; Anton, Gisela; Ardid Ramírez, Miguel; Aubert, J.-J.; Aublin, J.; Baret, Bruny; Basa, S. (Institute of Physics (IOP), 2021-04-10)
      Article
      Accés obert
      A search for astrophysical pointlike neutrino sources using the data collected by the ANTARES detector between 2007 January 29 and 2017 December 31 is presented. A likelihood method is used to assess the significance of ...

    • ANTARES upper limits on the multi-TeV neutrino emission from the GRBs detected by IACTs 

      Albert, A.; André, Michel; Anghinolfi, Marco; Anton, Gisela; Ardid Ramírez, Miguel; Aubert, J.-J.; Aublin, J.; Baret, B.; Basa, Stéphane (2021-03-01)
      Article
      Accés obert
      The first gamma-ray burst detections by Imaging Atmospheric Cherenkov Telescopes have been recently announced: GRB 190114C, detected by MAGIC, GRB 180720B and GRB 190829A, observed by H.E.S.S. A dedicated search for neutrinos ...

    • Approaching the exascale simulation of subsonic turbulence with smoothed particle hydrodynamics 

      Sanz Lechuga, Axel (Universitat Politècnica de Catalunya, 2022-09-09)
      Projecte Final de Màster Oficial
      Accés obert
      Turbulence is key to many astrophysical and cosmological scenarios. Hence, a correct depiction of it in numerical simulations is of capital importance. Kolmogorov's theory states that in the subsonic regime the energy ...

    • Architecture and performance of the KM3NeT front-end firmware 

      Aiello, S; Albert, Arnauld; Alves Garre, Sergio; Zineb, Aly; Ameli, Fabrizio; André, Michel; Androulakis, Giorgos; Anghinolfi, Marco; Anguita, M.; Anton, Gisela (International Society for Photo-Optical Instrumentation Engineers (SPIE), 2021-01-01)
      Article
      Accés obert
      The KM3NeT infrastructure consists of two deep-sea neutrino telescopes being deployed in the Mediterranean Sea. The telescopes will detect extraterrestrial and atmospheric neutrinos by means of the incident photons induced ...

    • Assessment of centre national d'Études spatiales real-time ionosphere maps in instantaneous precise real-time kinematic positioning over medium and long baselines 

      Tomaszewski, Dariusz; Wielgosz, Pawel; Rapinski, Jacek; Krypiak-Gregorczyk, Anna; Kazmierczak, Rafal; Hernández Pajares, Manuel; Yang, Heng; Orús Pérez, Raul (Multidisciplinary Digital Publishing Institute (MDPI), 2020-04-17)
      Article
      Accés obert
      Precise real-time kinematic (RTK) Global Navigation Satellite System (GNSS) positioning requires fixing integer ambiguities after a short initialization time. Originally, it was assumed that it was only possible at a ...

    • Assessment of global ionospheric maps performance by means of ionosonde data 

      Jerez, Gabriel Olivera; Hernández Pajares, Manuel; Prol, Fabricio dos Santos; Alves, Daniele Barroca Marra; Monico, João Francisco Galera (Multidisciplinary Digital Publishing Institute (MDPI), 2020-10-21)
      Article
      Accés obert
      This work presents a new method for assessing global ionospheric maps (GIM) using ionosonde data. The method is based on the critical frequency at the F2 layer directly measured by ionosondes to validate VTEC (vertical ...

    • Assessment of St. Patrick's Day 2015 Geomagnetic storm impact on EGNOS 

      Hernández Pajares, Manuel; Béniguel, Yannick; Orús Pérez, Raul; Prieto Cerdeira, Roberto; García Rigo, Alberto; Kinrade, J; Kauristie, Kirsti; Schlueter, Stefan; Serant, Damien; Krankowski, Andrzej; Secretan, Hugues; Sampedro Casis, Rodrigo; Prats Menéndez, Xavier (European Space Agency (ESA), 2015)
      Comunicació de congrés
      Accés restringit per política de l'editorial
      The Monitor project has been designed to monitor ionospheric events that would allow evaluating its impact on European GNSS Systems. It includes a network of ionospheric scintillation monitoring stations in various ...

    • Assessment of the capabilities and applicability of ionospheric perturbation indices provided in Europe 

      Borries, Claudia; Wilken, Volken; Jacobsen, Knut Stanley; García Rigo, Alberto; Dziak-Jankowska, Beata; Kervalishvili, Guram; Jakowski, Norbert; Tsagouri, Ioanna; Hernández Pajares, Manuel; Ferreira, Arthur A.; Hoque, Mainul (2020-08-01)
      Article
      Accés obert
      Perturbations in the ionosphere are of great interest not only for scientific research, but also for applications using transionospheric radiosignals (e.g. GNSS applications and HF communication), because the transmission ...

    • Astrophysical parameter determination using chaotic orbital regions 

      Nicolás Álvarez, Jorge (Universitat Politècnica de Catalunya, 2018-02-27)
      Projecte Final de Màster Oficial
      Accés obert
      Realitzat a/amb:   European Space Research and Technology Centre
      The goal of this thesis is to show that chaotic orbits of a dynamical system are advantageous (compared with regularnes) to determine the characteristic parameters of the system, and to give an estimate about the behaviour ...

    • Atmospheric neutrinos with the first detection units of KM3NeT/ARCA 

      Coniglione, R.; Markou, Christos; Müller, R R; Tzamariudaki, Ekaterini; Ageron, M.; Aiello, S; Albert, Arthur; Alshamsi, Mohammed; Alves Garre, Sergio; Aly, Zineb; Ambrosone, Antonio; Ameli, Fabrizio; André, Michel; Androulakis, Giorgos; Anghinolfi, Marco; Anton, Gisela; Ardid Ramírez, Miguel (arXiv, 2021)
      Text en actes de congrés
      Accés obert
      The KM3NeT Collaboration is constructing two deep-sea Cherenkov detectors in the Mediterranean Sea, aiming at neutrino oscillation measurements with the ORCA array, while the ARCA array aims at neutrino astronomy in the ...

    • Axions and the luminosity function of white dwarfs : the thin and thick discs, and the halo 

      Isern Vilaboy, Jordi; García-Berro Montilla, Enrique; Torres Gil, Santiago; Cojocaru, Elena Ruxandra; Catalán, S (Oxford University Press, 2018-08-01)
      Article
      Accés obert
      The evolution of white dwarfs is a simple gravothermal process of cooling. Since the shape of their luminosity function is sensitive to the characteristic cooling time, it is possible to use its slope to test the existence ...

    • Beta-decay half-lives and beta-delayed neutron emission probabilities for several isotopes of Au, Hg, Tl, Pb, and Bi, beyond N = 126 

      Caballero-Folch, R.; Domingo-Pardo, C; Agramunt Ros, Jorge; Calviño Tavares, Francisco; Cortés Rossell, Guillem Pere (2017-06-23)
      Article
      Accés obert
      Background: There have been measurements on roughly 230 nuclei that are beta-delayed neutron emitters. They range from 8He up to 150La. Apart from 210Tl, with a branching ratio of only 0.007%, no other neutron emitter has ...

    • Beyond the required LISA free-fall performance: new LISA pathfinder results down to 20 mu Hz 

      Armano, M.; Audley, H.; Baird, J.; Binetruy, P.; Ramos Castro, Juan José (American Institute of Physics (AIP), 2018-02-05)
      Article
      Accés obert
      In the months since the publication of the first results, the noise performance of LISA Pathfinder has improved because of reduced Brownian noise due to the continued decrease in pressure around the test masses, from a ...

    • Characterisation of the Hamamatsu photomultipliers for the KM3NeT Neutrino Telescope 

      Aiello, S; Ameli, F; André, Michel; Anghinolfi, Marco; Anton, G.; Ardid Ramírez, Miguel; Avgitas, T.; Bertin, V.; Bormuth, R.; Bouwhuis, M.C.; Puricelli, Stefano; Cherubini, Silvio; Coniglione, R.; Mannheim, Karl; Morganti, Michele; Pellegrino, Carlo; Piattelli, P.; Real, Del; Santangelo, A; Sharma, Aniruddh; Trovato, A.; Zaborov, D.; Zúñiga Román, Juan (2018-05-01)
      Article
      Accés obert
      The Hamamatsu R12199-02 3-inch photomultiplier tube is the photodetector chosen for the first phase of the KM3NeT neutrino telescope. About 7000 photomultipliers have been characterised for dark count rate, timing spread ...

    • Characteristics and energy dependence of recurrent galactic cosmic-ray flux depressions and of a forbush decrease with LISA Pathfinder 

      Armano, M.; Audley, H.; Baird, J.; Bassan, M.; Benella, S.; Lobo, J.A.; Ramos Castro, Juan José (2018-02-16)
      Article
      Accés obert
      Galactic cosmic-ray (GCR) energy spectra observed in the inner heliosphere are modulated by the solar activity, the solar polarity and structures of solar and interplanetary origin. A high counting rate particle detector ...

    • Classical and recurrent nova models 

      José Pont, Jordi; Casanova Bustamante, Jordi; García-Berro Montilla, Enrique; Hernanz Carbó, Margarita; Shore, Steven N.; Calder, A. (2011)
      Comunicació de congrés
      Accés obert
      Remarkable progress in the understanding of nova outbursts has been achieved through combined efforts in photometry, spectroscopy and numerical simulations. According to the thermonuclear runaway model, novae are powered ...

    • Coincident observations by the Kharkiv IS radar and ionosonde, DMSP and Arase (ERG) satellites, and FLIP model simulations: implications for the NRLMSISE-00 hydrogen density, plasmasphere, and ionosphere 

      Kotov, Dmytro; Richards, Philip G.; Truhlík, Vladimír; Hernández Pajares, Manuel (2018-08)
      Article
      Accés obert
      This paper reports the results of ionosphere and plasmasphere observations with the Kharkiv incoherent scatter radar and ionosonde, Defense Meteorological Satellite Program, and Arase (ERG) satellites and simulations with ...

    • Comments on: confirming geomagnetic Sfe by means of a solar flare detector based on GNSS 

      Hernández Pajares, Manuel; García Rigo, Alberto (2020-01-01)
      Article
      Accés obert
      We report two comments affecting the paper “Curto JJ, Juan JM & Timoté CC, 2019. Confirming geomagnetic Sfe by means of a solar flare detector based on GNSS. J Space Weather Space Clim 9: A42. https://doi.org/10.1051/sws ...