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arXiv · 1203.2071

Over-resolution of compact sources in interferometric observations

I. Marti-Vidal·M. A. Perez-Torres·A. P. Lobanov
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Abstract

We review the effects of source size in interferometric observations and focus on the cases of very compact sources. If a source is extremely compact and/or weak (so it is not possible to detect signature of source structure in the visibilities) we describe a test of hypothesis that can be used to set a strong upper limit to the size of the source. We also estimate the minimum possible size of a source whose structure can still be detected by an interferometer (i.e., the maximum theoretical over-resolution power of an interferometer), which depends on the overall observing time, the compactness in the array distribution, and the sensitivity of the receivers. As a result, and depending on the observing frequency, the over-resolution power of forthcoming ultra-sensitive arrays, like the Square Kilometer Array (SKA), may allow us to study details of sources at angular scales down to a few micro-as.

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I. Marti-Vidal, M. A. Perez-Torres, A. P. Lobanov. 2012-03-09. Over-resolution of compact sources in interferometric observations. https://doi.org/10.1051/0004-6361%2F201118334

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