Rotating hybrid axion-miniboson stars

Abstract

We construct rotating hybrid axion-miniboson stars (RHABSs), which are asymptotically flat, stationary, axially symmetric solutions of (3+1)-dimensional Einstein-Klein-Gordon theory. RHABSs consist of a axion field (ground state) and a free complex scalar field (first excited state). The solutions of the RHABSs have two types of nodes, including $^1S^2S$ state and $^1S^2P$ state. For different axion decay constants $f_a$, we present the mass $M$ of RHABSs as a function of the synchronized frequency $\omega$, as well as the nonsynchronized frequency $\omega_2$, and explore the mass $M$ versus the angular momentum $J$ for the synchronized frequency $\omega$ and the nonsynchronized frequency $\omega_2$ respectively. Furthermore, we study the effect of axion decay constant $f_a$ and scalar mass $\mu_2$ on the existence domain of the synchronized frequency $\omega$.