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arXiv · 1103.4872

Suzaku Detection of Diffuse Hard X-Ray Emission outside Vela X

Satoru Katsuda·Koji Mori·Robert Petre·Hiroya Yamaguchi·Hiroshi Tsunemi·Fabrizio Bocchino·Aya Bamba·Marco Miceli·John W. Hewitt·Tea Temim·Hiroyuki Uchida·Rie Yoshii
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Abstract

Vela X is a large, 3x2 degrees, radio-emitting pulsar wind nebula (PWN) powered by the Vela pulsar in the Vela supernova remnant. Using four Suzaku/XIS observations pointed just outside Vela X, we find hard X-ray emission extending throughout the fields of view. The hard X-ray spectra are well represented by a power-law. The photon index is measured to be constant at Gamma~2.4, similar to that of the southern outer part of Vela X. The power-law flux decreases with increasing distance from the pulsar. These properties lead us to propose that the hard X-ray emission is associated with the Vela PWN. The larger X-ray extension found in this work strongly suggests that distinct populations relativistic electrons form the X-ray PWN and Vela X, as was recently inferred from multiwavelength spectral modeling of Vela X.

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Satoru Katsuda, Koji Mori, Robert Petre, Hiroya Yamaguchi, Hiroshi Tsunemi, Fabrizio Bocchino, Aya Bamba, Marco Miceli, John W. Hewitt, Tea Temim, Hiroyuki Uchida, Rie Yoshii. 2011-03-24. Suzaku Detection of Diffuse Hard X-Ray Emission outside Vela X. https://doi.org/10.1093/pasj%2F63.sp3.s827

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