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Session 49 - Starburst Galaxies.
Display session, Tuesday, January 16
North Banquet Hall, Convention Center
We have calculated the dynamical evolution of dust grains embedded in a hot plasma close to a highly luminous source of radiation. We consider a single dust grain, initially positioned between 10^17 and 10^18 cm from an AGN or a type II supernova, and calculate its velocity as a function of distance from the source, taking into account radiation pressure, collisional drag and non-thermal sputtering of the grain by high energy collisions with ions. We will present results for a variety of grain sizes, gas densities and source luminosities. Preliminary calculations, neglecting photoelectric charging of the grains and acceleration of the gas, indicate that grains can reach substantial velocities, of order 0.1c in the case of acceleration by an AGN with L=10^44 ergs s^-1 in a plasma with n=100 cm^-3 and T=5\times10^6 K. We have also found that sputtering makes little difference to the dynamical evolution in the AGN case but can be important at high densities in the case of a grain accelerated by a Type II supernova, where large rates of sputtering can contribute to the acceleration of the grain.
Program listing for Tuesday