INVERSE COMPTON X-RAY EMISSION FROM SUPERNOVAE WITH COMPACT PROGENITORS: APPLICATION TO SN2011fe

Abstract

We present a generalized analytic formalism for the inverse Compton X-ray\nemission from hydrogen-poor supernovae and apply this framework to SN2011fe\nusing Swift-XRT, UVOT and Chandra observations. We characterize the optical\nproperties of SN2011fe in the Swift bands and find them to be broadly\nconsistent with a "normal" SN Ia, however, no X-ray source is detected by\neither XRT or Chandra. We constrain the progenitor system mass loss rate to be\nlower than 2x10^-9 M_sun/yr (3sigma c.l.) for wind velocity v_w=100 km/s. Our\nresult rules out symbiotic binary progenitors for SN2011fe and argues against\nRoche-lobe overflowing subgiants and main sequence secondary stars if >1% of\nthe transferred mass is lost at the Lagrangian points. Regardless of the\ndensity profile, the X-ray non-detections are suggestive of a clean environment\n(particle density < 150 cm-3) for (2x10^15<R<5x10^16) cm around the progenitor\nsite. This is either consistent with the bulk of material being confined within\nthe binary system or with a significant delay between mass loss and supernova\nexplosion. We furthermore combine X-ray and radio limits from Chomiuk et al.\n2012 to constrain the post shock energy density in magnetic fields. Finally, we\nsearched for the shock breakout pulse using gamma-ray observations from the\nInterplanetary Network and find no compelling evidence for a\nsupernova-associated burst. Based on the compact radius of the progenitor star\nwe estimate that the shock break out pulse was likely not detectable by current\nsatellites.\n