Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Calibration errors in interferometric radio polarimetry   Residual calibration errors are difficult to predict in interferometric radio
polarimetry because they depend on the employed observational calibration
strategy, encompassing the Stokes vector of the calibrator and parallactic
angle coverage. This work presents analytic derivations and simulations that
enable examination of residual on-axis instrumental leakage and position angle
errors for a suite of calibration strategies. The focus is on arrays comprising
alt-az antennas with common feeds over which parallactic angle is approximately
uniform. The results indicate that calibration schemes requiring parallactic
angle coverage in the linear feed basis (e.g. ALMA) need only observe over 30
deg, beyond which no significant improvements in calibration accuracy are
obtained. In the circular feed basis (e.g. VLA above 1 GHz), 30 deg is also
appropriate when the Stokes vector of the leakage calibrator is known a priori,
but this rises to 90 deg when the Stokes vector is unknown. These findings
illustrate and quantify concepts that were previously obscure rules of thumb.

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The categories of this paper are: gr-qc
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The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
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The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: stat
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The categories of this paper are: dg-ga
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The categories of this paper are: chem-ph
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The categories of this paper are: nlin
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The categories of this paper are: physics
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The categories of this paper are: quant-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
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The categories of this paper are: hep-th
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn