Spectral Identification of an Ancient Supernova using Light Echoes in the LMC

Abstract

We report the successful identification of the type of the supernova responsible for the supernova remnant SNR 0509-675 in the Large Magellanic Cloud (LMC) using Gemini spectra of surrounding light echoes. The ability to classify outbursts associated with centuries-old remnants provides a new window into several aspects of supernova research and is likely to be successful in providing new constraints on additional LMC supernovae as well as their historical counterparts in the Milky Way Galaxy (MWG). The combined spectrum of echo light from SNR 0509-675 shows broad emission and absorption lines consistent with a supernova (SN) spectrum. We create a spectral library consisting of 26 SNe Ia and 6 SN Ib/c that are time-integrated, dust-scattered by LMC dust, and reddened by the LMC and MWG. We fit these SN templates to the observed light echo spectrum using ${\chi }^2$ minimization as well as correlation techniques, and we find that overluminous 91T-like SNe Ia with $\dm15<0.9$ match the observed spectrum best.

12 pages, 18 Figures, to be published in ApJ

References in corpus (6)

• Determining the Type, Redshift, and Age of a Supernova Spectrum
• SN 2004aw: Confirming Diversity of Type Ic Supernovae
• Optical Spectroscopy of Type Ia Supernovae
• Lightcurves of Type Ia Supernovae from Near the Time of Explosion
• An Extremely Bright Echo Associated With SN 2002hh
• Determining the Type, Redshift, and Phase of a Supernova Spectrum

Cited by in corpus (5)

• Tycho Brahe's 1572 supernova as a standard type Ia explosion revealed from its light echo spectrum
• Scattered-Light Echoes from the Historical Galactic Supernovae Cassiopeia A and Tycho (SN 1572)
• The Stellar Ancestry of Supernovae in the Magellanic Clouds - I. the Most Recent Supernovae in the Large Magellanic Cloud
• The Kinematics of Kepler's Supernova Remnant as revealed by Chandra
• XMM-Newton X-ray spectra of the SNR 0509-67.5: data and models