Q-stars in scalar-tensor gravitational theories

Abstract

We study q-stars in Brans-Dicke gravitational theory. We find that when the Brans-Dicke constant, ${\omega }_{\text{BD}}$, tends to infinity, the results of General Relativity are reproduced. For other values of ${\omega }_{\text{BD}}$, the particle number, mass and radius of the star and the absolute value of the matter field are a few percent larger than in the case of General Relativity. We also investigate the general scalar-tensor gravitational theory and find that the star parameters are a few percent larger than in the case of General Relativity.

14 pages, to appear in Phys. Lett. B