Energetics and diagnostics of hot star disks

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Many types of massive stars rotate rapidly and are often associated with gaseous matter surrounding the star; sometimes dust and molecules are also present.  This material can be detected in the light we observe from the star. Often, this material has a disk-like distribution, but the processes which form and maintain these disks are not well understood.    My research will concentrate primarily on two particular types of hot stars, the Be stars and the B[e] stars, which are associated with disk-like distributions of material.  These stars represent an important group of stars for which our knowledge is severely lacking.  Compared to the Sun, these stars emit approximately a hundred to a million times more energy each second to their surroundings in the form of light which helps to shape the evolution of their parent galaxy. Since massive stars spend their supply of energy at such a large rate, and since their masses are only approximately ten times the mass of the Sun, they necessarily have short lifetimes. When massive stars have exhausted their energy supply near the end of their lifetime as a star, explosions can occur which further enrich their environments with both energy and chemical elements. My research focuses on constructing computer models of these disk-like regions.  The models predict details in the light that come from these objects, and then these predictions are compared with actual observations.  This analysis allows me to decipher the physical conditions surrounding these stars, such as temperature, density, and wind speed, so that I can try to understand what processes form and maintain these disks-like regions, and to understand the effects these stars have on their environments during their lifetimes.