Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatially resolved spectra of 3C galaxy nuclei   We present and discuss visible-wavelength long-slit spectra of four low
redshift 3C galaxies obtained with the STIS instrument on the Hubble Space
Telescope. The slit was aligned with near-nuclear jet-like structure seen in
HST images of the galaxies, to give unprecedented spatial resolution of the
galaxy inner regions. In 3C 135 and 3C 171, the spectra reveal clumpy emission
line structures that indicate outward motions of a few hundred km s$^{-1}$
within a centrally illuminated and ionised biconical region. There may also be
some low-ionisation high-velocity material associated with 3C 135. In 3C 264
and 3C 78, the jets have blue featureless spectra consistent with their
proposed synchrotron origin. There is weak associated line emission in the
innermost part of the jets with mild outflow velocity. These jets are bright
and highly collimated only within a circumnuclear region of lower galaxy
luminosity, which is not dusty. We discuss the origins of these central regions
and their connection with relativistic jets.

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The categories of this paper are: mtrl-th
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The categories of this paper are: gr-qc
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The categories of this paper are: bayes-an
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The categories of this paper are: cmp-lg
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The categories of this paper are: math
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The categories of this paper are: adap-org
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The categories of this paper are: econ
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The categories of this paper are: math-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-th
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The categories of this paper are: q-alg
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The categories of this paper are: quant-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: supr-con
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The categories of this paper are: comp-gas
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The categories of this paper are: stat