Astrophysical Bounds on Milli-Charged Particles in Models with a Paraphoton

Abstract

The upper bound on the number of relativistic species present at nucleosynthesis has been used to constrain particles with electric charge $ϵe$ ($10^{-8}<ϵ<1$). We correct the bound previously calculated for milli-charged particles that interact with a shadow photon. We also discuss the additional constraints from the properties of red giants and of Supernova 1987A.

Comments: 9 pages, figure available by fax