摘要: Alfven's critical ionization velocity (CIV) process involves collective and collisional interactions of a magnetoplasma streaming through a neutral gas. We report on numerical simulations of CIV using particle-in-cell plasma codes... 展开 Alfven's critical ionization velocity (CIV) process involves collective and collisional interactions of a magnetoplasma streaming through a neutral gas. We report on numerical simulations of CIV using particle-in-cell plasma codes including various collisional interactions. Fast electron heating is observed. The interplay between collisional and collective interactions renders the hot electron tail shorter than in non-CIV situations with collisionless wave-particle interactions without a neutral gas. Metastable states serve in the role of energy pooling and foster rapid ionization near the critical velocity. Line excitation is a severe energy loss mechanism. Charge exchange replenishes ion energy and is important during tight 'energy budget' situations near the critical velocity. Reprints. (jhd) 收起