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arXiv · 1011.4848

Observational Constraints on Interacting Dark Matter Model Without Dark Energy

Shuo Cao·Zong-Hong Zhu·Nan Liang
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Abstract

The interacting dark matter (IDM) scenario allows for the acceleration of the Universe without Dark Energy. We constrain the IDM model by using the newly revised observational data including $H(z)$ data and Union2 SNe Ia via the Markov chain Monte Carlo method. When mimicking the $\Lambda$CDM model, we obtain a more stringent upper limit to the effective annihilation term at $\kappa C_1\approx 10^{-3.4}\rm{Gyr}^{-1}$, and a tighter lower limit to the relevant mass of Dark Matter particles at $M_x\approx 10^{-8.6}\rm{Gev}$. When mimicking the $w$CDM model, we find that the effective equation of state of IDM is consistent with the concordance $\Lambda$CDM model and appears to be most consistent with the effective phantom model with a constant EoS for which $w<-1$.

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Shuo Cao, Zong-Hong Zhu, Nan Liang. 2010-11-22. Observational Constraints on Interacting Dark Matter Model Without Dark Energy. https://doi.org/10.1051/0004-6361%2F201016204

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