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Author KM3NeT Collaboration (Aiello, S. et al); Alves Garre, S.; Bariego-Quintana, A.; Calvo, D.; Carretero, V.; Garcia Soto, A.; Gozzini, S.R.; Hernandez-Rey, J.J.; Lazo, A.; Lessing, N.; Manczak, J.; Palacios Gonzalez, J.; Pastor Gomez, E.J.; Rahaman, U.; Real, D.; Saina, A.; Salesa Greus, F.; Sanchez Losa, A.; Zornoza, J.D.; Zuñiga, J.
Title Searches for neutrino counterparts of gravitational waves from the LIGO/Virgo third observing run with KM3NeT Type Journal Article
Year 2024 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages (up) 026 - 28pp
Keywords neutrino astronomy; gravitational waves / sources; neutrino experiments
Abstract The KM3NeT neutrino telescope is currently being deployed at two different sites in the Mediterranean Sea. First searches for astrophysical neutrinos have been performed using data taken with the partial detector configuration already in operation. The paper presents the results of two independent searches for neutrinos from compact binary mergers detected during the third observing run of the LIGO and Virgo gravitational wave interferometers. The first search looks for a global increase in the detector counting rates that could be associated with inverse beta decay events generated by MeV-scale electron anti -neutrinos. The second one focuses on upgoing track -like events mainly induced by muon (anti -)neutrinos in the GeV-TeV energy range. Both searches yield no significant excess for the sources in the gravitational wave catalogs. For each source, upper limits on the neutrino flux and on the total energy emitted in neutrinos in the respective energy ranges have been set. Stacking analyses of binary black hole mergers and neutron star -black hole mergers have also been performed to constrain the characteristic neutrino emission from these categories.
Address [Aiello, S.; Bruno, R.; Leonora, E.; Longhitano, F.; Randazzo, N.; Sinopoulou, A.; Tosta e Melo, I] INFN, Sez Catania, Via Santa Sofia 64, I-95123 Catania, Italy, Email: lestum@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 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:001208840500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6115
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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 1 Pages (up) 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 Caputo, A.; Regis, M.; Taoso, M.; Witte, S.J.
Title Detecting the stimulated decay of axions at radio frequencies Type Journal Article
Year 2019 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 03 Issue 3 Pages (up) 027 - 22pp
Keywords axions; dark matter theory; dark matter detectors; dwarfs galaxies
Abstract Assuming axion-like particles account for the entirety of the dark matter in the Universe, we study the possibility of detecting their decay into photons at radio frequencies. We discuss different astrophysical targets, such as dwarf spheroidal galaxies, the Galactic Center and halo, and galaxy clusters. The presence of an ambient radiation field leads to a stimulated enhancement of the decay rate; depending on the environment and the mass of the axion, the effect of stimulated emission may amplify the photon flux by serval orders of magnitude. For axion-photon couplings allowed by astrophysical and laboratory constraints (and possibly favored by stellar cooling), we find the signal to be within the reach of next-generation radio telescopes such as the Square Kilometer Array.
Address [Caputo, Andrea; Witte, Samuel J.] Univ Valencia, CSIC, Inst Fis Corpuscular, Apartado Correos 22085, E-46071 Valencia, Spain, Email: andrea0292@hotmail.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 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000461450100002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3944
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Author HAWC Collaboration (Albert, A. et al); Salesa Greus, F.
Title Evidence that Ultra-high-energy Gamma Rays Are a Universal Feature near Powerful Pulsars Type Journal Article
Year 2021 Publication Astrophysical Journal Letters Abbreviated Journal Astrophys. J. Lett.
Volume 911 Issue 2 Pages (up) L27 - 8pp
Keywords
Abstract The highest-energy known gamma-ray sources are all located within 0.degrees 5 of extremely powerful pulsars. This raises the question of whether ultra-high-energy (UHE; >56 TeV) gamma-ray emission is a universal feature expected near pulsars with a high spin-down power. Using four years of data from the High Altitude Water Cherenkov Gamma-Ray Observatory, we present a joint-likelihood analysis of 10 extremely powerful pulsars to search for subthreshold UHE gamma-ray emission correlated with these locations. We report a significant detection (>3 sigma), indicating that UHE gamma-ray emission is a generic feature of powerful pulsars. We discuss the emission mechanisms of the gamma rays and the implications of this result. The individual environment, such as the magnetic field and particle density in the surrounding area, appears to play a role in the amount of emission.
Address [Albert, A.; Dingus, B. L.; Durocher, M.; Harding, J. P.; Malone, K.] Los Alamos Natl Lab, Phys Div, Los Alamos, NM 87545 USA, Email: kmalone@lanl.gov
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 2041-8205 ISBN Medium
Area Expedition Conference
Notes WOS:000642352500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4796
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Author Figueroa, D.G.; Raatikainen, S.; Rasanen, S.; Tomberg, E.
Title Implications of stochastic effects for primordial black hole production in ultra-slow-roll inflation Type Journal Article
Year 2022 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 05 Issue 5 Pages (up) 027 - 48pp
Keywords inflation; primordial black holes; dark matter theory; massive black holes
Abstract We study the impact of stochastic noise on the generation of primordial black hole (PBH) seeds in ultra-slow-roll (USR) inflation with numerical simulations. We consider the non-linearity of the system by consistently taking into account the noise dependence on the inflaton perturbations, while evolving the perturbations on the coarse-grained background affected by the noise. We capture in this way the non-Markovian nature of the dynamics, and demonstrate that non-Markovian effects are subleading. Using the Delta N formalism, we find the probability distribution P(R) of the comoving curvature perturbation R. We consider inflationary potentials that fit the CMB and lead to PBH dark matter with i) asteroid, ii) solar, or iii) Planck mass, as well as iv) PBHs that form the seeds of supermassive black holes. We find that stochastic effects enhance the PBH abundance by a factor of O(10)-O(10(8)), depending on the PBH mass. We also show that the usual approximation, where stochastic kicks depend only on the Hubble rate, either underestimates or overestimates the abundance by orders of magnitude, depending on the potential. We evaluate the gauge dependence of the results, discuss the quantum-to-classical transition, and highlight open issues of the application of the stochastic formalism to USR inflation.
Address [Figueroa, Daniel G.] CSIC, Inst Fis Corpuscular IFIC, E-46980 Valencia, Spain, Email: daniel.figueoa@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 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000804493000010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5239
Permanent link to this record