Observing Inflationary Reheating
In the history of the Universe, reheating is the era which connects cosmic inflation, the accelerated expansion taking place at the earliest times, to the subsequent hot Big-Bang phase. This epoch is conceptually very important since all matter that we see around us was produced during this phase. This is also the first time the Universe acquired a temperature. Up to now, however, it was observationally poorly known. This letter shows that the current measurements of the Cosmic Microwave Background (CMB) anisotropies constrain the kinematic properties of the reheating era for most of the inflationary scenarios proposed so far. Quantitatively, the Planck 2013 CMB data impose an average reduction of the reheating prior volume by 40% in the whole space of models tested thereby giving non-trivial information onto the reheating temperature.
Reference url: http://arxiv.org/abs/1410.7958