HIGH-VELOCITY H I IS NOT ASSOCIATED WITH THE TeV SUPERNOVA REMNANT W51C
- National Astronomical Observatories, CAS, Beijing 100012 (China)
The recently detected TeV {gamma}-ray source HESS J1923+141 coincides with supernova remnant (SNR) W51C and the star-forming region W51B of the W51 complex. We construct H I absorption spectra of SNR W51C, H II regions G49.2-0.35 and G49.1-0.38 in W51B, and a nearby compact extragalactic source. Our study detects high-velocity (HV) H I clouds (above 83 km s{sup -1}) that coincide with W51B, but finds that the clouds are behind W51B. Both W51C and G49.2-0.35 have similar highest velocity absorption features at {approx}70 km s{sup -1}. The H II region G49.1-0.38 is behind the SNR because its H I absorption spectrum has a feature at 83 km s{sup -1}. These new results argue against previous claims that the SNR has shocked the HV H I clouds. Therefore, the TeV emission from the complex should not be associated with the HV H I clouds. W51C has a distance of about 4.3 kpc, smaller than the tangent point distance of 5.5 kpc in that direction, but still in the Sagittarius spiral arm.
- OSTI ID:
- 22130634
- Journal Information:
- Astrophysical Journal Letters, Vol. 769, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 2041-8205
- Country of Publication:
- United States
- Language:
- English
Similar Records
Is HESS J1912+101 Associated with an Old Supernova Remnant?
Fermi-LAT Discovery of Extended Gamma-Ray Emission in the Direction of Supernova Remnant W51C