From the Largest Spectroscopic Galaxy Survey to the Lightest Neutrino Mass

quarta-feira, 21 Novembro, 2018 - 11:00
Arthur Loureiro

Since the late 90's we have known that neutrinos oscillate between their three leptonian flavours, which lead to the 2015 Nobel Prize conclusion that these particles are massive. However, particle physics experiments can only tell us about the mass difference between some neutrino species and, consequently, their minimum mass. The neutrino mass hierarchy and the maximum value for the sum of their masses are still unknown. Cosmology, on the other hand, is sensitive to different aspects of neutrino physics since the number of massive neutrino species and the total sum of neutrino masses influence the evolution and formation of structure in the Universe. In this talk, I will present how a spherical harmonic analysis of the Baryon Oscillation Spectroscopic Survey (BOSS) large-scale structure galaxy sample can help set constraints on the sum of neutrino masses, their mass hierarchy and the mass of the lightest neutrino family. When combining the BOSS sample with Cosmic Microwave Background data from the Planck Satellite, Big Bang Nucleosynthesis constraints, and the latest SNe Type Ia data from the Pantheon compilation, we are able to obtain reliable neutrino mass constraints using physically motivated prior models.