Observation of the CIV effect in interstellar clouds: a speculation on the physical mechanism for their existence

Observations of neutral hydrogen (H I) emission profiles produced by gas in the local interstellar medium are found to be characterized by four linewidth regimes. Dominant and pervasive features have widths on average of 5.2, 13, and 31 km/s, and a very broad component approximately 50 km/s wide. A striking coincidence exists between these linewidths and the magnitudes of the critical ionization velocities of the most abundant atomic species in interstellar space: 6 km/s for sodium and calcium; 13 km/s for carbon, oxygen, and nitrogen; 31 km/s for helium; and 51 km/s for hydrogen. The data relate to observations near neutral hydrogen structures that are filamentary.