Axion-Like-Particles from X-ray excess in galaxy clusters?

by Alexandre Payez (desy)

Friday 17 Jan 2014, 12:00 → 13:00 Europe/Berlin

seminar room 3a, building 1b (DESY Hamburg)

The aim of this journal club is to give the audience a general idea of the developments of the paper S. Angus, J. Conlon, M. C. D. Marsh, A. Powell, and L. Witkowski [1312.3947], in which it is argued that a cosmic axion background would produce a soft X-ray excess as seen in galaxy clusters, and in particular in Coma. In this work, they link astrophysical observations with dark radiation and string cosmology, with an emphasis on the phenomenology. Keeping this approach, we will discuss the current astrophysical situation of the soft X-ray excess in galaxy clusters, and the observational consequences of such a cosmic axion background.