The Suzaku Key Project of the Kepler Supernova Remnant: A Status Report
Abstract
The Kepler supernova remnant (SNR) is a historical (SN 1604) Type Ia SNR with a peculiar progenitor that exploded in the ambient medium modified by stellar winds. We detect atomic emission lines from trace ejecta elements Mn and Cr in the Kepler SNR using our initial 100 ks Suzaku observation. The detection of these low abundant metal species produced by incomplete Si-burning in the Type Ia SN provides a unique opportunity to reveal the progenitor's metallicity. We also detect K line emission from the Ni-rich ejecta which was produced in the nuclear statistical equilibrium at the deepest core of the progenitor. As the start of our Suzaku Key Project of the Kepler SNR to place a tight constraint on the progenitor's metallicity, we performed 220 ks background observations to reduce the systematic errors on the Mn and Cr line flux measurements. We report on the refined measurements of the Mn to Cr line flux ratio using our new background data. Our preliminary results suggest an enhanced metallicity (several times the Solar) for the Kepler SNR's progenitor. The completion of our Suzaku Key Project with the upcoming deep Kepler observation will be essential to pin down the suggested high metallicity of the progenitor by significantly reducing the large statistical uncertainties embedded in the current data.
- Publication:
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AAS/High Energy Astrophysics Division #11
- Pub Date:
- March 2010
- Bibcode:
- 2010HEAD...11.1815P