Kepler’S supernova: An OVERLUMINOUS type Ia event interacting with a massive circumstellar medium at a very late phase

Journal Article · Mon Jul 20 04:00:00 EDT 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/808/1/49· OSTI ID:22882871

Katsuda, Satoru; Maeda, Yoshitomo; Ozaki, Masanobu ^[1]; Mori, Koji ^[2]; Maeda, Keiichi ^[3]; Tanaka, Masaomi ^[4]; Koyama, Katsuji; Tsunemi, Hiroshi; Nakajima, Hiroshi ^[5]; Petre, Robert ^[6]

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1. Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210 (Japan)
2. Department of Applied Physics and Electronic Engineering, Faculty of Engineering, University of Miyazaki, 1-1 Gakuen Kibanadai-Nishi, Miyazaki 889-2192 (Japan)
3. Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan)
4. National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan)
5. Department of Earth and Space Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043 (Japan)
6. Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

We have analyzed XMM-Newton, Chandra, and Suzaku observations of three similarly aged, ejecta-dominated supernova remnants (SNRs), Kepler's SNR, Tycho's SNR, and SNR 0509-67.5, to investigate the properties of the SN ejecta and the circumstellar medium (CSM). By simply comparing the X-ray spectra, we find that line intensity ratios of iron-group elements (IGEs) to intermediate-mass elements (IMEs) for Kepler's SNR and SNR 0509-67.5 are much higher than those for Tycho's SNR. Given that Tycho's SNR and SNR 0509-67.5 are thought to be the remnants of a typical SN Ia and an overluminous SN Ia, respectively, we argue that Kepler is the product of an overlumious SN Ia. This inference is supported by our spectral modeling, which reveals the IGE and IME masses, respectively, to be 0.95{sub −0.37}{sup +0.34} M{sub ⊙} and 0.12{sub −0.05}{sup +0.19} M{sub ⊙} (Kepler's SNR), 0.75{sub −0.15}{sup +0.51} M{sub ⊙} and 0.34{sub −0.25}{sup +0.08} M{sub ⊙} (SNR 0509-67.5), and 0.35{sub −0.15}{sup +0.55} M{sub ⊙} and 0.70{sub −0.28}{sup +0.12} M{sub ⊙} (Tycho's SNR). We find that the CSM component in Kepler's SNR consists of tenuous diffuse gas (∼0.3 M{sub ⊙}) present throughout the entire remnant, plus dense knots (∼0.035 M{sub ⊙}). Since both of them show N overabundance, their origin would be CNO-processed material from the progenitor system. The mass of the diffuse CSM allows us to infer the pre-SN mass-loss rate to be ∼1.5×10{sup −5}(v{sub w}/10 km s{sup −1}) M{sub ⊙} yr{sup −1}. The dense knots have slow proper motions and relatively small ionization timescales; hence, they were likely located a few parsecs away from the progenitor at the explosion. We thus argue that Kepler's SN was an overluminous (91T-like) event that recently started to interact with the massive CSM. This supports the possible link between 91T-like SNe and “Ia-CSM” SNe.

• OSTI ID: 22882871
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 808; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United Kingdom
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
EXPLOSIONS
INTERSTELLAR SPACE
IONIZATION
IRON
MASS TRANSFER
PROPER MOTION
STELLAR WINDS
SUPERNOVA REMNANTS
TYPE I SUPERNOVAE
X RADIATION
X-RAY SPECTRA