Cosmology of neutrinos and extra light particles after WMAP3
Marco Cirelli, Alessandro Strumia
Abstract
We study how present data probe standard and non-standard properties of neutrinos and the possible existence of new light particles, freely-streaming or interacting, among themselves or with neutrinos. Our results include: sum mnu < 0.40 eV at 99.9% C.L.; that extra massless particles have abundance Delta Nnu = 2 pm 1 if freely-streaming and Delta Nnu = 0 pm 1.3 if interacting; that 3 interacting neutrinos are disfavored at about 4 sigma. We investigate the robustness of our results by fitting to different sub-sets of data. We developed our own cosmological computational tools, somewhat different from the standard ones.
Create a lesson
Related papers
On binary pulsars and the force of gravity
Davor Palle
Tidal torques. A critical review of some techniques
Michael Efroimsky, James G. Williams
Dynamics of a Spherical Accretion Shock with Neutrino Heating and Alpha-Particle Recombination
Rodrigo Fernández, Christopher Thompson
Asymptotically FRW black holes
J. T. Firouzjaee, Reza Mansouri
Reaction of Accretion Disks to Abrupt Mass Loss During Binary Black Hole Merger
Sean M. O'Neill, M. Coleman Miller, Tamara Bogdanovic et al.
A Gamma-Ray Burst/Pulsar for Cosmic-Ray Positrons with a Dark Matter-like Spectrum
Kunihito Ioka