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arXiv · 1303.3546

G306.3-0.9: A newly discovered young galactic supernova remnant

Mark Reynolds·Shyeh Loi·Tara Murphy·Jon Miller·Dipankar Maitra·Kayhan Gultekin·Neil Gehrels·Jamie Kennea·Michael Siegel·Jonathan Gelbord·Paul Kuin·Vanessa Moss·Sarah Reeves·William Robbins·Bryan Gaensler·Rubens Reis·Robert Petre
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Abstract

We present X-ray and radio observations of the new Galactic supernova remnant (SNR) G306.3-0.9, recently discovered by Swift. Chandra imaging reveals a complex morphology, dominated by a bright shock. The X-ray spectrum is broadly consistent with a young SNR in the Sedov phase, implying an age of 2500 yr for a distance of 8 kpc, plausibly identifying this as one of the 20 youngest Galactic SNRs. Australia Telescope Compact Array (ATCA) imaging reveals a prominent ridge of radio emission that correlates with the X-ray emission. We find a flux density of ~ 160 mJy at 1 GHz, which is the lowest radio flux recorded for a Galactic SNR to date. The remnant is also detected at 24microns, indicating the presence of irradiated warm dust. The data reveal no compelling evidence for the presence of a compact stellar remnant.

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Mark Reynolds, Shyeh Loi, Tara Murphy, Jon Miller, Dipankar Maitra, Kayhan Gultekin, Neil Gehrels, Jamie Kennea, Michael Siegel, Jonathan Gelbord, Paul Kuin, Vanessa Moss, Sarah Reeves, William Robbins, Bryan Gaensler, Rubens Reis, Robert Petre. 2013-03-14. G306.3-0.9: A newly discovered young galactic supernova remnant. https://doi.org/10.1088/0004-637x/766/2/112

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