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Non-Thermal X-ray and Radio Emission from the SNR N 157B

ohn R. Dickel·Shiya Wang
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Abstract

The supernova remnant N 157B contains a pulsar and three distinct synchrotron components with rather unusual properties. 1) A somewhat irregular elliptical pulsar wind nebula (PWN) visible in both X-ray and radio wavelengths. The nebula is quite symmetrical with an extent of about 10 X 5 parsecs but offset along the long axis by about 4 pc from the pulsar position. It is apparently the result of a short-lived injection of energetic particles, perhaps starting at the time of explosion. 2) A very bright X-ray shock region located just outside the pulsar position in the edge of the PWN. This is undetected in the radio. We attribute this feature to a new burst of particles from the pulsar suggesting there are multiple episodes rather than continuous injection. 3) The beginning of a radio synchrotron shell on the southern side of the SNR where thermal X-rays appear to arise suggesting that N 157B is starting to become a composite SNR.

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ohn R. Dickel, Shiya Wang. 2003-08-13. Non-Thermal X-ray and Radio Emission from the SNR N 157B. https://arxiv.org/abs/astro-ph/0308240

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