Séminaire Doctoral / Seminar PhD |
| « Big bang nucleosynthesis: the role of neutrinos » |
|
Julien Froustey |
| Big bang nucleosynthesis (BBN) is considered as one of the pillars of the standard model of cosmology due to the matching between the predicted abundances of light elements, produced in the first minutes after the Big Bang, and experimental observations. The calculation of those abundances via numerical codes requires to describe a very rich physics: nuclear reaction rates, thermodynamics of the background, weak reaction rates... In this talk, I will focus on the particular role of neutrinos. At the epoch of BBN, neutrinos decouple from the electromagnetic plasma of photons, electrons, positrons, while the latter annihilate, releasing entropy that mainly reheat the photons. A precise description of this decoupling is crucial to determine the neutrino spectra and temperatures, which are the key parameters to understand the various ways in which neutrinos influence BBN's outcome. |
|
vendredi 19 février 2021 - 16:00 Webinaire, Institut d'Astrophysique |
| Page web du séminaire / Seminar's webpage |