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arXiv · 1708.04179

Rapid X-ray variations of the Geminga pulsar wind nebula

C. Y. Hui·Jongsu Lee·A. K. H. Kong·P. H. T. Tam·J. Takata·K. S. Cheng·Dongsu Ryu
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Abstract

A recent study by Posselt et al. (2017) reported the deepest X-ray investigation of the Geminga pulsar wind nebula (PWN) by using \emph{Chandra X-ray Observatory}. In comparison with previous studies of this system, a number of new findings have been reported and we found these suggest the possible variabilities in various components of this PWN. This motivates us to carry out a dedicated search for the morphological and spectral variations of this complex nebula. We have discovered variabilities on timescales from a few days to a few months from different components of the nebula. The fastest change occurred in the circumstellar environment at a rate of 80 per cent of the speed of light. One of the most spectacular results is the wiggling of a half light-year long tail as an extension of the jet, which is significantly bent by the ram pressure. The jet wiggling occurred at a rate of about 20 per cent of the speed of light. This twisted structure can possibly be a result of a propagating torsional Alfven wave. We have also found evidence of spectral hardening along this tail for a period of about nine months.

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C. Y. Hui, Jongsu Lee, A. K. H. Kong, P. H. T. Tam, J. Takata, K. S. Cheng, Dongsu Ryu. 2017-08-14. Rapid X-ray variations of the Geminga pulsar wind nebula. https://doi.org/10.3847/1538-4357%2Faa862c

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