RADIATION HYDRODYNAMIC RADIAL OSCILLATIONS - GENERAL-RELATIVISTIC TREATMENT

Diverse luminosity variabilities exist in many accretion systems like galactic X-ray sources. Quasi-periodic oscillation (QPO) in luminosity is one example seen in low-mass X-ray. binaries. To extend the work o f Miller and Park[1] who investigated the radiation hydrodynamic insta bility with Newtonian approximation as the driving mechanism for the h orizontal and flaring branch QPOs, we study the stability of the radia tion dominated spherical accretion flow to radial perturbations in the framework of general relativity. Effects of curved spacetime and radi ation moments in the fixed and comoving frames are rigorously treated. Both local and global modes are found through linear analyses and the result is compared with those of previous works.