Improved CLEAN reconstructions for rotation measure synthesis with maximum likelihood estimation

Abstract

The CLEAN deconvolution algorithm has well-known limitations due to the restriction of locating point source model components on a discretized grid. In this letter we demonstrate that these limitations are even more pronounced when applying CLEAN in the case of Rotation Measure (RM) synthesis imaging. We suggest a modification that uses Maximum Likelihood estimation to adjust the CLEAN-derived sky model. We demonstrate through the use of mock one-dimensional RM synthesis observations that this technique shows significant improvement over standard CLEAN and gives results that are independent of the chosen image pixelization. We suggest using this simple modification to CLEAN in upcoming polarization sensitive sky surveys.

5 pages, 4 figures, submitted to A&A

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Cited by in corpus (5)

• Comparison of algorithms for determination of rotation measure and Faraday structure I. 1100 - 1400 MHz
• Detection of a ~20 kpc coherent magnetic field in the outskirt of merging spirals: the Antennae galaxies
• Properties of Intrinsic Polarization Angle Ambiguities in Faraday Tomography
• Faraday dispersion functions of galaxies
• Finding a faint polarized signal in wide-band radio data