Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Link Between X-ray Emission Lines and Radio Jets in 4U 1630-47?   Recently, Diaz Trigo et al. reported an XMM-Newton detection of
relativistically Doppler-shifted emission lines associated with steep-spectrum
radio emission in the stellar-mass black hole candidate 4U 1630-47 during its
2012 outburst. They interpreted these lines as indicative of a baryonic jet
launched by the accretion disk. Here we present a search for the same lines
earlier in the same outburst using high-resolution X-ray spectra from the
Chandra High-Energy Transmission Grating Spectrometer. While our observations
(eight months prior to the XMM-Newton campaign) also coincide with detections
of steep spectrum radio emission by the Australia Telescope Compact Array, we
find no evidence for any relativistic X-ray emission lines. Indeed, despite
$\sim5\times$ brighter radio emission, our Chandra spectra allow us to place an
upper limit on the flux in the blueshifted Fe XXVI line that is
$\gtrsim20\times$ weaker than the line observed by Diaz Trigo et al. We explore
several scenarios that could explain our differing results, including
variations in the geometry of the jet or a mass-loading process or jet baryon
content that evolves with the accretion state of the black hole. We also
consider the possibility that the radio emission arises in an interaction
between a jet and the nearby ISM, in which case the X-ray emission lines might
be unrelated to the radio emission.

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The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-th
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The categories of this paper are: quant-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: nlin
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
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The categories of this paper are: adap-org
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The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
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The categories of this paper are: q-alg
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The categories of this paper are: cond-mat
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The categories of this paper are: cmp-lg
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The categories of this paper are: stat
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The categories of this paper are: math