F. De Paolis, G. Ingrosso, A. A. Nucita, D. Vetrugno, V. G. Gurzadyan, A. L. Kashin, H. G. Khachatryan, S. Mirzoyan, Ph. Jetzer, A. Qadir
Baryons constitute about 4% of our universe, but most of them are missing and
we do not know where and in what form they are hidden. This constitute the
so-called missing baryon problem. A possibility is that part of these baryons
are hidden in galactic halos. We show how the 7-year data obtained by the WMAP
satellite may be used to trace the halo of the nearby giant spiral galaxy M31.
We detect a temperature asymmetry in the M31 halo along the rotation direction
up to about 120 kpc. This could be the first detection of a galactic halo in
microwaves and may open a new way to probe hidden baryons in these relatively
less studied galactic objects using high accuracy CMB measurements.
View original:
http://arxiv.org/abs/1202.2969
No comments:
Post a Comment