Relativistic Radiative Flow in a Luminous Disk

Radiatively driven transfer flow perpendicular to a luminous disk wasexamined under a fully special relativistic treatment, taking into accountradiation transfer. The flow was assumed to be vertical, and the gravity, thegas pressure, and the viscous heating were ignored. In order to construct theboundary condition at the flow top, the magic speed above the flat source wasre-examined, and it was found that the magic speed above a moving source canexceed that above a static source ($\sim 0.45~c$). Then, the radiatively drivenflow in a luminous disk was numerically solved, from the flow base (disk``inside''), where the flow speed is zero, to the flow top (disk ``surface''),where the optical depth is zero. For a given optical depth and appropriateinitial conditions at the flow base, where the flow starts, a loaded mass inthe flow was obtained as an eigenvalue of the boundary condition at the flowtop. Furthermore, a loaded mass and the flow final speed at the flow top wereobtained as a function of the radiation pressure at the flow base; the flowfinal speed increases as the loaded mass decreases. Moreover, the flow velocityand radiation fields along the flow were obtained as a function of the opticaldepth. Within the present treatment, the flow three velocity $v$ is restrictedto be within the range of $v < c/\sqrt{3}$, which is the relativistic soundspeed, due to the relativistic effect.Comment: 8 pages, 5 figure