Suzaku Observation of HESS J1825-137: Discovery of Largely-Extended X-rays near from PSR J1826-1334

H. Uchiyama; H. Matsumoto; T. G. Tsuru; K. Koyama; A. Bamba

doi:10.1093/pasj/61.sp1.s189

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arXiv · 0808.3436

Suzaku Observation of HESS J1825-137: Discovery of Largely-Extended X-rays near from PSR J1826-1334

H. Uchiyama·H. Matsumoto·T. G. Tsuru·K. Koyama·A. Bamba

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Abstract

We observed the brightest part of HESS J1825-137 with the Suzaku XIS, and found diffuse X-rays extending at least up to 15' (~ 17 pc) from the pulsar PSR J1826-1334. The spectra have no emission line, and are fitted with an absorbed power-law model. The X-rays, therefore, are likely due to synchrotron emission from a pulsar wind nebula. The photon index near at the pulsar (r<1.5') is 1.7 while those in r=1.5-16 are nearly constant at Gamma=2.0. The spectral energy distribution of the Suzaku and H.E.S.S. results are naturally explained by a combined process; synchrotron X-rays and gamma-rays by the inverse Compton of the cosmic microwave photons by high-energy electrons in a magnetic field of 7 micro G. If the electrons are accelerated at the pulsar, the electrons must be transported over 17 pc in the synchrotron life time of 1900 yr, with a velocity of > 8.8 times 10^3 km s^{-1}.

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H. Uchiyama, H. Matsumoto, T. G. Tsuru, K. Koyama, A. Bamba. 2008-08-26. Suzaku Observation of HESS J1825-137: Discovery of Largely-Extended X-rays near from PSR J1826-1334. https://doi.org/10.1093/pasj%2F61.sp1.s189

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