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arXiv · astro-ph/0607307

The X-ray synchrotron emission of RCW 86 and the implications for its age

Abstract

We report here X-ray imaging spectroscopy observations of the northeastern shell of the supernova remnant RCW 86 with Chandra and XMM-Newton. Along this part of the shell the dominant X-ray radiation mechanism changes from thermal to synchrotron emission. We argue that both the presence of X-ray synchrotron radiation and the width of the synchrotron emitting region suggest a locally higher shock velocity of V_s = 2700 km/s and a magnetic field of B = 24+/-5 microGauss. Moreover, we also show that a simple power law cosmic ray electron spectrum with an exponential cut-off cannot explain the broad band synchrotron emission. Instead a concave electron spectrum is needed, as predicted by non-linear shock acceleration models. Finally, we show that the derived shock velocity strengthens the case that RCW 86 is the remnant of SN 185.

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Jacco Vink, Johan Bleeker, Kurt van der Heyden, Andrei Bykov, Aya Bamba, Ryo Yamazaki. 2006-07-13. The X-ray synchrotron emission of RCW 86 and the implications for its age. https://doi.org/10.1086/507628

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