A Cosmic Axion Background and the cluster soft X-Ray excess

by Dr David Marsh (Oxfor University - UK)

Wednesday 19 Mar 2014, 15:00 → 16:30 Europe/Rome

Sala Riunioni (Dipartimento di Fisica e Astronomia)

I will discuss how string theory axions may generically give rise to a background of relativistic axions in the present day universe. Such axions would contribute to the dark radiation of the universe and may already have been detected through the long-standing soft X-Ray excess in galaxy clusters