Theory Seminar (High Energy/Cosmology)
Events on Tuesday, April 26th, 2016
- Simulating the neutrino sky: Cosmological probes of neutrino mass
- Time: 3:30 pm
- Place: 5280 Chamberlin Hall
- Speaker: JD Emberson, Argonne National Laboratory
- Abstract: Neutrinos are second only to photons as the most abundant particle in the Universe, yet remain poorly understood due to their weak interaction with other matter. In particular, individual neutrino masses remain an elusive property for both particle physicists and cosmologists. Recently, it has been proposed that individual neutrino mass may be constrained from a unique dipole distortion in the matter density field induced by the relative flow between cold dark matter (CDM) and neutrinos. We study this effect by modifying the cosmology code CUBEP3M to evolve neutrino N-body particles alongside CDM. We have performed the world's largest cosmological N-body simulation, containing roughly 3 trillion neutrino plus CDM particles, completed using 86% of the Tianhe-2 supercomputer. In this talk, we discuss preliminary analysis of the simulation data in regards to the neutrino dipole distortion. We also present a new independent probe of neutrino mass that was numerically detected in our simulation data. This new effect is due to neutrino free streaming, which sources local variations in the relative abundance of neutrinos, creating a differential bias that may skew the luminosity function of galaxies.
- Host: Amol Upadhye