Highlights from Hitomi observations of non-Perseus targets
Abstract
Before the tragic loss of the spacecraft due to attitude control problems, Hitomi observed three supernova remnants (SNR), N132D, G21.5-0.9, and the Crab Nebula, with the main purpose of initial in-orbit calibration. Here we present some scientific highlights of these observations.N132D is a middle-aged, core-collapse SNR in the Large Magellanic Cloud (LMC). It was observed after the Perseus cluster. Even though the exposure was very short, the SXS clearly resolves the fine structure of He-like S K-shell emission. We detect a significant redshift that is consistent with the line-of-sight velocity of the LMC. Fe K emission is redshifted even more significantly, with a corresponding velocity of ~2000 km/s. This suggests a non-uniform velocity distribution of the Fe ejecta, probably due to an asymmetric supernova explosion.G21.5-0.9 is a young plerionic composite-type SNR. Powered by the 62 ms rotation-powered pulsar J1833-1034, the SNR is dominated by non-thermal emission from the pulsar wind nebula, with extended limb-brightening and knots of X-ray emission. The Hitomi SXS, SXI, and HXI observations provide a high-statistics wide-band spectrum from a single satellite. We are currently searching for 1) emission or absorption line features, 2) a spectral break in the continuum, and 3) the pulse period. The status of the analysis and results will be presented.The Crab was observed after all the instruments aboard Hitomi were turned on. We successfully obtain the pulse profile with all of the instruments. The X-ray polarization is being studied with the HXI and SGD. We also search for emission/absorption lines with the SXS, but no features have so far been significantly detected. We discuss the results in light of constraining the nature of the Crab's progenitor explosion.
- Publication:
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American Astronomical Society Meeting Abstracts #229
- Pub Date:
- January 2017
- Bibcode:
- 2017AAS...22920804Y