Photoionization Edges of Galaxies and the HI Column Density Distribution

摘要: We look for a photoionization feature in the H I column density distri­bution. Our model assumes lines come from rotationally-supported disks dark matter potential wells (i.e., galaxies), and outer edges of these are ionized by metagalactic radiation field. The predicted result is flattening distribution N ~ 1017.5 cm−2 to 1020.5 cm−2. preliminary results do not show strong evidence this feature.