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arXiv · 1212.2664

Chandra observations of SN 1987A: the soft X-ray light curve revisited

E. A. Helder·P. S. Broos·D. Dewey·E. Dwek·R. McCray·S. Park·J. L. Racusin·S. A. Zhekov·D. N. Burrows
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Abstract

We report on the present stage of SN 1987A as observed by the Chandra X-ray Observatory. We reanalyze published Chandra observations and add three more epochs of Chandra data to get a consistent picture of the evolution of the X-ray fluxes in several energy bands. We discuss the implications of several calibration issues for Chandra data. Using the most recent Chandra calibration files, we find that the 0.5-2.0 keV band fluxes of SN 1987A have increased by ~6 x 10 ^-13 erg s^-1 cm^-2 per year since 2009. This is in contrast with our previous result that the 0.5-2.0 keV light curve showed a sudden flattening in 2009. Based on our new analysis, we conclude that the forward shock is still in full interaction with the equatorial ring.

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E. A. Helder, P. S. Broos, D. Dewey, E. Dwek, R. McCray, S. Park, J. L. Racusin, S. A. Zhekov, D. N. Burrows. 2012-12-11. Chandra observations of SN 1987A: the soft X-ray light curve revisited. https://doi.org/10.1088/0004-637x/764/1/11

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