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arXiv · 2205.15579

System equivalent flux density of Stokes I, Q, U, V of a polarimetric interferometer

A. T. Sutinjo·D. C. X. Ung·M. Sokolowski
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Abstract

We present the system equivalent flux density (SEFD) expressions for all four Stokes parameters: I, Q, U, V. The expressions were derived based on our derivation of SEFD I (for Stokes I) and subsequent extensions of that work to phased array and multipole interferometers. The key to the derivation of the SEFD Q, U, V expressions is to recognize that the noisy estimates of Q, U, V can be written as the trace of a matrix product. This shows that the SEFD I is a special case, where the general case involves a diagonal or anti-diagonal 2x2 matrix interposed in the matrix multiplication. Following this step, the relation between the SEFD for I and Q, U, V becomes immediately evident. We present example calculations for a crossed dipole based on the formulas derived and the comparison between simulation and observation using the Murchison Widefield Array (MWA).

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A. T. Sutinjo, D. C. X. Ung, M. Sokolowski. 2022-05-31. System equivalent flux density of Stokes I, Q, U, V of a polarimetric interferometer. https://doi.org/10.1051/0004-6361%2F202243512

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