タイトル | Galactic H I and the interstellar medium in Ursa Major |
著者(英) | Jahoda, Keith; Mccammon, Dan; Lockman, Felix J. |
著者所属(英) | Wisconsin Univ.|NASA Goddard Space Flight Center|National Radio Astronomy Observatory |
発行日 | 1990-05-01 |
言語 | eng |
内容記述 | Sensitive neutral hydrogen measurements have been made over a 100 square degree field in Ursa Major. The observations cover the area which has the least neutral hydrogen and probably the least interstellar matter of any direction in the sky. It is likely that this data set contains every line of sight that intersects a total H I column density of less than 6.5 x 10 to the 19th/sq cm. The smallest colum density is estimated to be 4.4 + or - 0.5 x 10 to the 19th/sq cm. Observations at 10 arcmin angular resolution reveal little structure that is not seen at 21 arcmin resolution, and it is believed that the estimates of the total H I column density are accurate on yet smaller angular scales. The lowest N(H I) area is also extremely deficient in H-alpha emission, and shows no evidence for significant amounts of H2. |
NASA分類 | ASTROPHYSICS |
レポートNO | 90A32190 |
権利 | Copyright |
URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/356675 |