Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: VLBI detections of a source weaker than 100 mJy at 86 GHz   We use a new phase-calibration strategy to calibrate the phase of 86 GHz VLBI
observations of the FR I radio galaxy NGC 4261. Instead of switching between a
calibrator source and the target source, the target was observed while rapidly
switching between the target frequency and a lower reference frequency.
Self-calibration at the reference frequency yielded phase corrections which
were multiplied with the frequency ratio and applied to the target frequency
visibilities. The resulting detection of NGC 4261 is, to our knowledge, the
first of NGC 4261 with 86 GHz VLBI, and it is also the weakest source so far
detected with VLBI at that frequency.

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The categories of this paper are: nucl-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: dg-ga
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The categories of this paper are: math-ph
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The categories of this paper are: nlin
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The categories of this paper are: gr-qc
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The categories of this paper are: supr-con
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The categories of this paper are: q-bio
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The categories of this paper are: solv-int
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The categories of this paper are: plasm-ph
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The categories of this paper are: adap-org
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The categories of this paper are: hep-lat