The Persistence of Memory, or How the X-Ray Spectrum of SNR 0509–67.5 Reveals the Brightness of Its Parent Type Ia Supernova

We examine the dynamics and X-ray spectrum of the young Type Ia supernova remnant 0509–67.5 in the context of the recent results obtained from the optical spectroscopy of its light echo. Our goal is to estimate the kinetic energy of the supernova explosion using Chandra and XMM-Newton observations of the supernova remnant, thus placing the birth event of 0509–67.5 in the sequence of dim-to-bright Type Ia supernovae. We base our analysis on a standard grid of one-dimensional delayed detonation explosion models, together with hydrodynamic and X-ray spectral calculations of the supernova remnant evolution. From the remnant dynamics and the properties of the O, Si, S, and Fe emission in its X-ray spectrum we conclude that 0509–67.5 originated ~400 yr ago from a bright, highly energetic Type Ia explosion similar to SN 1991T. Our best model has a kinetic energy of 1.4 × 10⁵¹ erg and synthesizes 0.97 M_☉ of ⁵⁶Ni. These results are in excellent agreement with the age estimate and spectroscopy from the light echo. We have thus established the first connection between a Type Ia supernova and its supernova remnant based on a detailed quantitative analysis of both objects.