Emission Spectrum of Dust in a Cooling Gas

摘要

The emission spectrum of dust undergoing substantial temperature fluctuations behind strong shocks (>100 km/s) is modeled. The model includes calculating the temperature distribution function of the dust particles owing to stochastic heating by electrons in the ambient plasma, as well as the features of the resulting spectral distribution of the emission from the dust. As the surrounding plasma cools, the emission spectrum changes and differs noticeably from the "quasi-Planck" spectrum of isothermal dust (or a superposition of spectra of this sort). The character of these changes can be used for diagnostics of the thermal state of the plasma. Objects where these effects can be significant are discussed briefly.