The quark-hadron phase transition in a rotating compact star has been studied. The NLZ (nonlinear consistent zero point energy) model has been used for the hadronic sector and the MIT bag model has been used for the quark sector. It has been found that rotating twin star (third family) solutions are obtained up to $\Omega \approx 4000s^{-1}$. Stars that are rotating faster than this limit do not show twin star solution. A backbending in the moment of inertia is also observed in the supermassive rest mass sequences. The braking index is found to diverge for a star having a larger region of mixed phase.

• Received 18 October 2004

DOI:https://doi.org/10.1103/PhysRevC.71.048801