Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Systematic effects in apparent proper motion of radio sources   The galactocentric rotation of the Solar system generates the systematic
effect in proper motions known as 'secular aberration drift'. This tiny effect
(about five microseconds per year) in the quasar proper motion can be measured
by VLBI. However, the motions of relativistic jets from the active
extragalactic nuclei can reach several hundred microseconds per year and mimic
the proper motion of the observed radio sources. These apparent motions exceed
the secular aberration drift by factor of 10-100. In this paper we search the
ways to overcome the difficulties and discuss our estimates of the secular
aberration drift using OCCAM software.

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The categories of this paper are: q-bio
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The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
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The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: adap-org
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The categories of this paper are: hep-lat
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The categories of this paper are: cs
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The categories of this paper are: eess
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The categories of this paper are: econ
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The categories of this paper are: q-fin
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The categories of this paper are: nlin
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The categories of this paper are: math
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The categories of this paper are: patt-sol
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The categories of this paper are: cond-mat