Séminaire Doctoral / Seminar PhD |
| « High energy and ultra-high energy cosmic neutrinos : from birth to death » |
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Valentin Decoene |
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High-energy neutrinos are produced by the interaction of ultra-high-energy cosmic rays (charged nuclei that bombard the Earth with energies > 10^17 eV, and that are routinely detected), with astrophysical backgrounds. The sources of these neutrinos, detected with IceCube up to energies ~10^15 eV, have not been identified yet.
Our journey will begin at the birth of our high energy neutrino. We will explore a potential source of high energy neutrinos, the neutron-star-merger. Motivated by the recent multi-messenger observations of GW170817/GRB170817, we will first explore the production of ultra-high-energy cosmic rays and secondary high-energy neutrinos in neutron-star mergers. I will focus on the production of neutrinos via cosmic-ray interactions on the surrounding kilonova ejecta. Following our newly born high energy neutrino during its journey in the cosmos to the earth, we will discuss its observation with astroparticles detectors using the radio-technique. Finally we will look at the extreme energy end (>10^17 eV). These ultra-high energy neutrinos have not been observed yet. Because of their low flux, their detection requires to build gigantic detectors. The recent progress on the detection of astroparticles using radio-techniques has launched a novel idea: deploying 100,000s of radio antennas over 100,000s of km^2 in order to achieve the required sensitivities. I will introduce the GRAND (Giant Radio Array for Neutrino Detection) project, and show with a geometrical modelling how different array layouts and ground topologies can enhance the neutrino sensitivity. I will also present the latest results on the angular resolution based on this layout, and show how we expect it to be sensitive enough to perform neutrino astronomy. |
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vendredi 10 mai 2019 - 15:00 Salle Entresol Daniel Chalonge, Institut d'Astrophysique |
| Page web du séminaire / Seminar's webpage |