The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
A Almela - One of the best experts on this subject based on the ideXlab platform.
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improved limit to the diffuse flux of ultrahigh energy Neutrinos from the pierre auger observatory
Physical Review D, 2015Co-Authors: A Aab, P Abreu, M Aglietta, E J Ahn, Al I Samarai, I F M Albuquerque, I Allekotte, P Allison, A AlmelaAbstract:Neutrinos in the cosmic ray flux with energies near 1 EeV and above are detectable with the Surface Detector array (SD) of the Pierre Auger Observatory. We report here on searches through Auger data from 1 January 2004 until 20 June 2013. No neutrino candidates were found, yielding a limit to the diffuse flux of ultrahigh energy Neutrinos that challenges the Waxman-Bahcall bound predictions. Neutrino identification is attempted using the broad time structure of the signals expected in the SD stations, and is efficiently done for Neutrinos of all flavors interacting in the atmosphere at large zenith angles, as well as for "Earth-skimming" neutrino interactions in the case of tau Neutrinos. In this paper the searches for downward-going Neutrinos in the zenith angle bins 60°-75°and 75°-90°as well as for upward-going Neutrinos, are combined to give a single limit. The 90% C.L. single-flavor limit to the diffuse flux of ultrahigh energy Neutrinos with an E-2 spectrum in the energy range 1.0×1017eV-2.5×1019eV is Eν2dNν/dEν<6.4×10-9GeVcm-2s-1sr-1.
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search for point like sources of ultra high energy Neutrinos at the pierre auger observatory and improved limit on the diffuse flux of tau Neutrinos
The Astrophysical Journal, 2012Co-Authors: P Abreu, M Ahlers, M Aglietta, E J Ahn, I F M Albuquerque, I Allekotte, P Allison, D Allard, J Allen, A AlmelaAbstract:The surface detector array of the Pierre Auger Observatory can detect Neutrinos with energy E_ν between 10^17 eV and 10^20 eV from point-like sources across the sky south of +55 degrees and north of -65 degrees declinations. A search has been performed for highly inclined extensive air showers produced by the interaction of Neutrinos of all flavors in the atmosphere (downward-going Neutrinos), and by the decay of tau leptons originating from tau neutrino interactions in Earth's crust (Earth-skimming Neutrinos). No candidate Neutrinos have been found in data up to 2010 May 31. This corresponds to an equivalent exposure of ∼3.5 years of a full surface detector array for the Earth-skimming channel and ∼2 years for the downward-going channel. An improved upper limit on the diffuse flux of tau Neutrinos has been derived. Upper limits on the neutrino flux from point-like sources have been derived as a function of the source declination. Assuming a differential neutrino flux k_PS . E_nu^-2. from a point-like source, 90% confidence level upper limits for k_PS at the level of ≈5x10^-7 and 2.5x10^-6 GeV cm^-2 s^-1 have been obtained over a broad range of declinations from the searches for Earth-skimming and downward-going Neutrinos, respectively.
Daming Wei - One of the best experts on this subject based on the ideXlab platform.
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Neutrinos from choked jets accompanied by type ii supernovae
The Astrophysical Journal, 2018Co-Authors: Alexander Kusenko, Shigehiro Nagataki, Yizhong Fan, Daming WeiAbstract:The origin of the IceCube Neutrinos is still an open question. Upper limits from diffuse gamma-ray observations suggest that the neutrino sources are either distant or hidden from gamma-ray observations. It is possible that the Neutrinos are produced in jets that are formed in core-collapsing massive stars and fail to break out, the so-called choked jets. We study Neutrinos from the jets choked in the hydrogen envelopes of red supergiant stars. Fast photo-meson cooling softens the neutrino spectrum, making it hard to explain the PeV Neutrinos observed by IceCube in a one-component scenario, but a two-component model can explain the spectrum. Furthermore, we predict that a newly born jet-driven type-II supernova may be observed to be associated with a neutrino burst detected by IceCube.
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Neutrinos from choked jets accompanied by type ii supernovae
arXiv: High Energy Astrophysical Phenomena, 2018Co-Authors: Alexander Kusenko, Shigehiro Nagataki, Yizhong Fan, Daming WeiAbstract:The origin of the IceCube Neutrinos is still an open question. Upper limits from diffuse gamma-ray observations suggest that the neutrino sources are either distant or hidden from gamma-ray observations. It is possible that the Neutrinos are produced in jets that are formed in the core-collapsing massive stars and fail to break out, the so-called choked jets. We study Neutrinos from the jets choked in the hydrogen envelopes of red supergiant stars. Fast photo-meson cooling softens the neutrino spectrum, making it difficult to explain the PeV Neutrinos observed by IceCube in a one-component scenario, but a two-component model can explain the spectrum. Furthermore, we predict that a newly born jet-driven type-II supernova may be observed to be associated with a neutrino burst detected by IceCube.
E Figueroafeliciano - One of the best experts on this subject based on the ideXlab platform.
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solar neutrino physics with low threshold dark matter detectors
Physical Review D, 2015Co-Authors: J Billard, Louis E Strigari, E FigueroafelicianoAbstract:Dark matter detectors will soon be sensitive to Solar Neutrinos via two distinct channels: coherent neutrino-nucleus and neutrino-electron elastic scatterings. We establish an analysis method for extracting Solar model properties and neutrino properties from these measurements, including the possible effects of sterile Neutrinos which have been hinted at by some reactor experiments and cosmological measurements. Even including sterile Neutrinos, through the coherent scattering channel, a 1 ton-year exposure with a lowthreshold background free Germanium detector could improve on the current measurement of the normalization of the 8 B Solar neutrino flux down to 3% or less. Combining with the neutrino-electron elastic scattering data will provide constraints on both the high- and low-energy survival probability and will improve on the uncertainty on the active-to-sterile mixing angle by a factor of 2. This sensitivity to active-to-sterile transitions is competitive and complementary to forthcoming dedicated short baseline sterile neutrino searches with nuclear decays. Finally, we show that such solar neutrino physics potentials can be reached as long as the signal-to-noise ratio is better than 0.1.
S Couvidat - One of the best experts on this subject based on the ideXlab platform.
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solar Neutrinos helioseismology and the solar internal dynamics
Reports on Progress in Physics, 2011Co-Authors: S Turckchieze, S CouvidatAbstract:Neutrinos are fundamental particles ubiquitous in the Universe and whose properties remain elusive despite more than 50 years of intense research activity. This review illustrates the importance of solar Neutrinos in astrophysics, nuclear physics and particle physics. After a description of the historical context, we remind the reader of the noticeable properties of these particles and of the stakes of the solar neutrino puzzle. The standard solar model triggered persistent efforts in fundamental physics to predict the solar neutrino fluxes, and its constantly evolving predictions have been regularly compared with the detected neutrino signals. Anticipating that this standard model could not reproduce the internal solar dynamics, a seismic solar model was developed which enriched theoretical neutrino flux predictions with in situ observation of acoustic and gravity waves propagating in the Sun. This seismic model contributed to the stabilization of the neutrino flux predictions. This review recalls the main historical steps, from the pioneering Homestake mine experiment and the GALLEX-SAGE experiments capturing the first proton–proton Neutrinos. It emphasizes the importance of the SuperKamiokande and SNO detectors. Both experiments demonstrated that the solar-emitted electron Neutrinos are partially transformed into other neutrino flavors before reaching the Earth. This sustained experimental effort opens the door to neutrino astronomy, with long-base lines and underground detectors. The success of BOREXINO in detecting the 7Be neutrino signal alone instills confidence in physicists' ability to detect each neutrino source separately. It justifies the building of a new generation of detectors to measure the entire solar neutrino spectrum in greater detail, as well as supernova Neutrinos. A coherent picture has emerged from neutrino physics and helioseismology. Today, new paradigms take shape in these two fields: Neutrinos are massive particles, but their masses are still unknown, and the research on the solar interior focuses on the dynamical aspects and on the signature of dark matter. The magnetic moment of the neutrino begins to be an actor in stellar evolution. The third part of the review is dedicated to this prospect. The understanding of the crucial role of both rotation and magnetism in solar physics benefits from SoHO, SDO and PICARD space observations, and from a new prototype, GOLF-NG. The magnetohydrodynamical view of the solar interior is a new way of understanding the impact of the Sun on the Earth's environment and climate. For now, the particle and stellar challenges seem decoupled, but this is only a superficial appearance. The development of asteroseismology—with the COROT and KEPLER spacecraft—and of neutrino physics will both contribute to improvements in our understanding of, for instance, supernova explosions. This shows the far-reaching impact of neutrino and stellar astronomy.
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solar Neutrinos helioseismology and the solar internal dynamics
arXiv: Solar and Stellar Astrophysics, 2010Co-Authors: S Turckchieze, S CouvidatAbstract:Neutrinos are fundamental particles ubiquitous in the Universe. Their properties remain elusive despite more than 50 years of intense research activity. In this review we remind the reader of the noticeable properties of these particles and of the stakes of the solar neutrino puzzle. The Standard Solar Model triggered persistent efforts in fundamental Physics to predict the solar neutrino fluxes, and its constantly evolving predictions have been regularly compared to the detected neutrino signals. Anticipating that this standard model could not reproduce the internal solar dynamics, a SEismic Solar Model was developed which enriched theoretical neutrino flux predictions with in situ observation of acoustic waves propagating in the Sun. This review reminds the historical steps, from the pioneering Homestake detection, the GALLEX- SAGE captures of the first pp Neutrinos and emphasizes the importance of the Superkamiokande and SNO detectors to demonstrate that the solar-emitted electronic Neutrinos are partially transformed into other neutrino flavors before reaching the Earth. The success of BOREXINO in detecting the 7 Be neutrino signal justifies the building of a new generation of detectors to measure the entire solar neutrino spectrum. A coherent picture emerged from neutrino physics and helioseismology. Today, new paradigms take shape: determining the masses of Neutrinos and the research on the Sun is focusing on the dynamical aspects and on signature of dark matter. The third part of the review is dedicated to this prospect. The understanding of the crucial role of both rotation and magnetism in solar physics benefit from SoHO, SDO, and PICARD space observations. For now, the particle and stellar challenges seem decoupled, but this is only a superficial appearance. The development of asteroseismology shows the far-reaching impact of Neutrino and Stellar Astronomy.
Alexander Kusenko - One of the best experts on this subject based on the ideXlab platform.
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Neutrinos from choked jets accompanied by type ii supernovae
The Astrophysical Journal, 2018Co-Authors: Alexander Kusenko, Shigehiro Nagataki, Yizhong Fan, Daming WeiAbstract:The origin of the IceCube Neutrinos is still an open question. Upper limits from diffuse gamma-ray observations suggest that the neutrino sources are either distant or hidden from gamma-ray observations. It is possible that the Neutrinos are produced in jets that are formed in core-collapsing massive stars and fail to break out, the so-called choked jets. We study Neutrinos from the jets choked in the hydrogen envelopes of red supergiant stars. Fast photo-meson cooling softens the neutrino spectrum, making it hard to explain the PeV Neutrinos observed by IceCube in a one-component scenario, but a two-component model can explain the spectrum. Furthermore, we predict that a newly born jet-driven type-II supernova may be observed to be associated with a neutrino burst detected by IceCube.
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Neutrinos from choked jets accompanied by type ii supernovae
arXiv: High Energy Astrophysical Phenomena, 2018Co-Authors: Alexander Kusenko, Shigehiro Nagataki, Yizhong Fan, Daming WeiAbstract:The origin of the IceCube Neutrinos is still an open question. Upper limits from diffuse gamma-ray observations suggest that the neutrino sources are either distant or hidden from gamma-ray observations. It is possible that the Neutrinos are produced in jets that are formed in the core-collapsing massive stars and fail to break out, the so-called choked jets. We study Neutrinos from the jets choked in the hydrogen envelopes of red supergiant stars. Fast photo-meson cooling softens the neutrino spectrum, making it difficult to explain the PeV Neutrinos observed by IceCube in a one-component scenario, but a two-component model can explain the spectrum. Furthermore, we predict that a newly born jet-driven type-II supernova may be observed to be associated with a neutrino burst detected by IceCube.
