arXiv 0902.32362009-02-18astro-ph.GAastro-ph.HE

A VLA Archive Observation of the Youngest Known Galactic Supernova Remnant G1.9+0.3

Yolanda Gomez, Luis F. Rodriguez

备注：: 5 pages, 2 figures

英文摘要：

We present the analysis of an unpublished VLA archive observation made at 1.49 GHz in 1989 toward the supernova remnant G1.9+0.3, the youngest such Galactic object known. This observation agrees with the time evolution in angular size previously reported. We derive an expansion rate of 0.46 +- 0.11 % per year and an age of 220+45-70 yr for the remnant by comparing the 1985 and 1989 images.

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