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arXiv · 2401.08278

Hitomi-HXT deconvolution imaging of the Crab Nebula dazzled by the Crab pulsar

Mikio Morii·Yoshitomo Maeda·Hisamitsu Awaki·Kouichi Hagino·Manabu Ishida·Koji Mori
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Abstract

We develop a new deconvolution method to improve the angular resolution of the Crab Nebula image taken by the Hitomi HXT. Here, we extend the Richardson-Lucy method by introducing two components for the nebula and the Crab pulsar with regularization for smoothness and flux, respectively, and deconvolving multi-pulse-phase images simultaneously. The deconvolved nebular image at the lowest energy band of 3.6--15 keV looks consistent with the Chandra X-ray image. Above 15 keV, we confirm that the NuSTAR's findings that the nebula size decreases in higher energy bands. We find that the north-east side of the nebula becomes dark in higher energy bands. Our deconvolution method can be applicable for any telescope images of faint diffuse objects containing a bright point source.

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Mikio Morii, Yoshitomo Maeda, Hisamitsu Awaki, Kouichi Hagino, Manabu Ishida, Koji Mori. 2024-01-16. Hitomi-HXT deconvolution imaging of the Crab Nebula dazzled by the Crab pulsar. https://arxiv.org/abs/2401.08278

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