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arXiv · 1511.02488

Evidence for Two-Component Jet in Sw J1644+57

Jiuzhou Wang·Weihua Lei·Dingxiong Wang·Wei Xie·Bing Zhang
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Abstract

The continued observations of Sw J1644+57 in X-ray and radio bands accumulated a rich data set to study the relativistic jet launched in this tidal disruption event. We find that the re-brightening feature in the radio light curve can be naturally explained by the two-component jet model. The possible origin of this structured jet are the Blandford-Znajek and Blandford-Payne mechanisms. We also show that this two-component jet model can interpret the two kinds of quasi-periodic variations in the X-ray light curve: a 200 second quasi-periodic oscillation (QPO) and a 2.7-day quasi-periodic variation. The latter is interpreted by a precessing outer jet launched near the Bardeen-Petterson radius of a warped disk. The $\sim$ 200s QPO could be associated with a second, narrower jet sweeping the observer line-of-sight periodically, which is launched from a spinning black hole in the misaligned direction with respect to the black hole's angular momentum.

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Jiuzhou Wang, Weihua Lei, Dingxiong Wang, Wei Xie, Bing Zhang. 2015-11-08. Evidence for Two-Component Jet in Sw J1644+57. https://arxiv.org/abs/1511.02488

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