Constraints on Dark Matter annihilation and Its Equation of State after Planck Data

Lixin Xu

Published 2013-12-13, updated 2013-12-17Version 2

In this paper, the annihilation of dark matter $f_d\epsilon_0$ with nonzero equation of state $w_{dm}$ was studied by using the currently available cosmic observations which include the geometric and dynamic measurements. The constrained results show they are anti-correlated and are $w_{dm}=0.000390_{-0.000753}^{+0.000754}$ and $f_d\epsilon_0=1.172_{-1.172}^{+0.243}$ respectively in $1\sigma$ regions. With the including of possible annihilation of dark matter, no significant deviation from $\Lambda$CDM model was found in the $1\sigma$ region.