Observational constraints on interacting dark matter model without dark energy

We constrain the Interacting Dark Matter (IDM) scenario which allows for the acceleration of the Universe without Dark Energy (Basilakos & Plionis 2009) by using the newly revised observational data including H(z) data and Union2 SNe Ia via the Markov Chain Monte Carlo method. For the mimickingCDM model, we obtain a more stringent upper limit of the effective annihilation term atC1 � 10 −4 Gyr −1 , and a tighter lower limit of the relevant mass of Dark Matter particles at Mx � 10 −8 Gev. For the mimicking wCDM model, we find the effective equation of state for the spec ial IDM model favors the effective phantom model with a constant EoS (w < −1).