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arXiv · 1903.00299

Gamma-rays from SS433: evidence for periodicity

Kajwan Rasul·Paula M. Chadwick·Jamie A. Graham·Anthony M. Brown
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Abstract

In this paper we present our study of the gamma-ray emission from the microquasar SS433. Integrating over 9 years of Fermi-LAT \textsc{pass8} data, we detect SS433 with a significance of ~13$σ$ in the 200 to 500 MeV photon energy range, with evidence for an extension in the direction of the w1 X-ray `hotspot`. A temporal analysis reveals evidence for modulation of SS433's gamma-ray emission with the precession period of its relativistic jet. This suggests that at least some of SS433's gamma-ray emission originates close to the object rather than from the jet termination regions.

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Kajwan Rasul, Paula M. Chadwick, Jamie A. Graham, Anthony M. Brown. 2019-03-01. Gamma-rays from SS433: evidence for periodicity. https://doi.org/10.1093/mnras%2Fstz559

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