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arXiv · 1603.01971

Suzaku observations of the hard X-ray spectrum of Vela Jr

Sawako Takeda·Aya Bamba·Yukikatsu Terada·Makoto S. Tashiro·Satoru Katsuda·Ryo Yamazaki·Yutaka Ohira·Wataru Iwakiri
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Abstract

We report the results of Suzaku observations of the young supernova remnant, Vela Jr.\ (RX J0852.0$-$4622), which is known to emit synchrotron X-rays, as well as TeV gamma-rays. Utilizing 39 Suzaku mapping observation data from Vela Jr., a significant hard X-ray emission is detected with the hard X-ray detector (HXD) from the north-west TeV-emitting region. The X-ray spectrum is well reproduced by a single power-law model with the photon index of 3.15$^{+1.18}_{-1.14}$ in the 12--22 keV band. Compiling this with the soft X-ray spectrum simultaneously observed with the X-ray imaging spectrometer (XIS) onboard Suzaku, we find that the wide-band X-ray spectrum in the 2--22 keV band is reproduced with a single power-law or concave broken power-law model, which are statistically consistent with each other. Whichever the model of a single or broken power-law is appropriate, clearly the spectrum has no rolloff structure. Applying this result to the method introduced in \citet{yama2014}, we find that one-zone synchrotron model with electron spectrum having a power-law plus exponential cutoff may not be applicable to Vela Jr.

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Sawako Takeda, Aya Bamba, Yukikatsu Terada, Makoto S. Tashiro, Satoru Katsuda, Ryo Yamazaki, Yutaka Ohira, Wataru Iwakiri. 2016-03-07. Suzaku observations of the hard X-ray spectrum of Vela Jr. https://doi.org/10.1093/pasj%2Fpsw036

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