Doppler Velocity Measurement of Fe Ejecta in Kepler's Supernova Remnant
Abstract
We present asymmetric kinematics of the hot Fe ejecta in Kepler's SNR, the remnant of the SN Ia observed in 1604, revealed using Doppler velocity measurement (Kasuga et al. 2018, PASJ, 70, 5, 88). The ejecta kinematics of young SNRs is an important clue to understanding the explosion mechanism of their progenitors. The line-of-sight velocity of the shock-heated ejecta can only be measured by the Doppler shift of emission lines in the X-ray band. Using Chandra ~741 ksec observations, we discovered significantly red shifted bulk Fe ejecta near the center of the SNR together with several blue shifted Fe clumps. This suggests possible asymmetricity of the progenitor explosion particularly at the hot dense core. Another SN Ia remnant Tycho, on the other hand, shows more symmetric expansion structure (e.g., Williams et al. 2017, Sato & Hughes 2017), suggesting variety in SN Ia progenitor system and/or explosion mechanism.
- Publication:
-
Supernova Remnants: An Odyssey in Space after Stellar Death II
- Pub Date:
- June 2019
- Bibcode:
- 2019sros.confE.193K