My research centers on theoretical study of compact objects (neutron stars and black holes, pulsars), radiative processes (radiative transfer, stellar atmospheres, effects of strong magnetic fields), astrophysical fluid dynamics and MHD (accretion disks, density waves, binaries, stellar oscillations, gravitational collapse), gravitational waves, atomic physics and condensed matter in astrophysi...

An optimal maximum-likelihood technique for computing point-source image centroids from many, slightly o set, CCD frames is presented. The method is especially useful for measuring stellar proper motions from data taken with the Wide Field and Planetary Camera aboard the HST, and also provides a means to identify very compact non-stellar sources. We work though the example problem of obtaining ...

Solid phase material exists in low density astrophysical environments, from stellar atmospheres to interstellar clouds, from current times to early phases of the universe. We consider the origin, composition and evolution of solid phase materials in the particular case of stellar outer atmospheres, as representative of many conditions. Also considered are the dynamics and interactions in circum...