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arXiv · 0804.2317

The radio expansion and brightening of the very young supernova remnant G1.9+0.3

Abstract

Recent radio observations of the small Galactic supernova remnant G1.9+0.3 made at 4.86 GHz with the VLA are presented, and compared with earlier observations at 1.49 GHz which have a comparable resolution (10 x 4 arcsec^2). These show that the radio emission from this remnant has expanded significantly, by about 15 per cent over 23 years, with a current outer diameter of approximately 92 arcsec. This expansion confirms that G1.9+0.3 is the youngest Galactic remnant yet identified, only about 150 years old at most. Recent, lower resolution, 1.43-GHz observations are also discussed, and the integrated flux densities from these and the 4.86-GHz observations are compared with earlier results. This shows that the integrated flux density of G1.9+0.3 has been increasing recently.

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BibTeXRIS

D. A. Green, S. P. Reynolds, K. J. Borkowski, U. Hwang, I. Harrus, R. Petre. 2008-04-15. The radio expansion and brightening of the very young supernova remnant G1.9+0.3. https://doi.org/10.1111/j.1745-3933.2008.00484.x

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