Energy extraction and the centre of mass energy in slowly rotating Chern-Simons black holes

In this paper we study the effects of the coupling constant of the Chern-Simons modified gravity on some physical properties of black holes. The Hawking mass is one of the proposed definitions of quasilocal mass. We find that, for slowly rotating Chern-Simons black hole, the Hawking mass is independent of the coupling constant. Next we show the dependence of the centre of mass energy for two neutral colliding particles on the coupling constant and the rotation parameter. We investigate energy extraction through Penrose process and find that the energy gain and efficiency of the Penrose process are independent of this coupling constant.