Rotating Hayward's regular black hole as particle accelerator

Recently, Banados, Silk and West (BSW) demonstrated that the extremal Kerr black hole can act as a particle accelerator with arbitrarily high center-of-mass energy (E-CM) when the collision takes place near the horizon. The rotating Hayward's regular black hole, apart from Mass (M) and angular momentum (a), has a new parameter g (g > 0 is a constant) that provides a deviation from the Kerr black hole. We demonstrate that for each g, with M = 1, there exist critical a(E) and r(H)(E), which corresponds to a regular extremal black hole with degenerate horizons, and a(E) decreases whereas r(H)(E) increases with increase in g. While a < a(E) describe a regular non-extremal black hole with outer and inner horizons. We apply the BSW process to the rotating Hayward's regular black hole, for different g, and demonstrate numerically that the E-CM diverges in the vicinity of the horizon for the extremal cases thereby suggesting that a rotating regular black hole can also act as a particle accelerator and thus in turn provide a suitable framework for Plank-scale physics. For a non-extremal case, there always exist a finite upper bound for the E-CM, which increases with the deviation parameter g.