Formation of Fluctuations in the Molecular Slab via Isobaric Thermal Instability

摘要

The frictional heating by ion-neutral drift is calculated and its effect onisobaric thermal instability is carried out. Ambipolar drift heating ofone-dimensional self-gravitating magnetized molecular slab is used under theassumptions of quasi-magnetohydrostatic and local ionization equilibrium. Wesee that ambipolar drift heating is inversely proportional to density and itsvalue in some regions of the slab can be significantly larger than the averageheating rates of cosmic rays and turbulent motions. The results show that theisobaric thermal instability can occur in some regions of the slab; thereforeit may produce the slab fragmentation and formation of the AU-scalecondensations.