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Title: DETECTION OF EXTREMELY BROAD WATER EMISSION FROM THE MOLECULAR CLOUD INTERACTING SUPERNOVA REMNANT G349.7+0.2

Journal Article · · Astrophysical Journal
 [1];  [2];  [3];  [4]
  1. SETI Institute, 189 N. Bernardo Avenue, Mountain View, CA 94043 (United States)
  2. CRESST/University of Maryland, Baltimore County, Baltimore, MD 21250 (United States)
  3. SOFIA Science Center, NASA Ames Research Center, MS 232-11, Moffett Field, CA 94035 (United States)
  4. Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192-0106 (United States)

We performed Herschel HIFI, PACS, and SPIRE observations toward the molecular cloud interacting supernova remnant G349.7+0.2. An extremely broad emission line was detected at 557 GHz from the ground state transition 1{sub 10}-1{sub 01} of ortho-water. This water line can be separated into three velocity components with widths of 144, 27, and 4 km s{sup −1}. The 144 km s{sup −1} component is the broadest water line detected to date in the literature. This extremely broad line width shows the importance of probing shock dynamics. PACS observations revealed three additional ortho-water lines, as well as numerous high-J carbon monoxide (CO) lines. No para-water lines were detected. The extremely broad water line is indicative of a high velocity shock, which is supported by the observed CO rotational diagram that was reproduced with a J-shock model with a density of 10{sup 4} cm{sup −3} and a shock velocity of 80 km s{sup −1}. Two far-infrared fine-structure lines, [O i] at 145 μm and [C ii] line at 157 μm, are also consistent with the high velocity J-shock model. The extremely broad water line could be simply from short-lived molecules that have not been destroyed in high velocity J-shocks; however, it may be from more complicated geometry such as high-velocity water bullets or a shell expanding in high velocity. We estimate the CO and H{sub 2}O densities, column densities, and temperatures by comparison with RADEX and detailed shock models.

OSTI ID:
22518847
Journal Information:
Astrophysical Journal, Vol. 812, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
Country of Publication:
United States
Language:
English