RM-Tools: Software for Analyzing Polarized Radio Spectra

Cameron L. Van Eck; Cormac R. Purcell; Lerato Baidoo; Alec J. M. Thomson; Yik Ki Ma; Lindsey Oberhelman; Erik Osinga; Shannon Vanderwoude; Jennifer L. West; Shinsuke Ideguchi; Dylan M. Paré; Jane F. Kaczmarek; Tony Willis; Takuya Akahori; Craig S. Anderson; B. M. Gaensler; Shane O'Sullivan; Xiaohui Sun; Ariel D. Amaral; C. J. Riseley; Jeroen Stil; Xiang Zhang

arXiv · 2601.20092

RM-Tools: Software for Analyzing Polarized Radio Spectra

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Abstract

Polarization observations using modern radio telescopes cover large numbers of frequency channels over broad bandwidths, and require advanced techniques to extract reliable scientific results. We present RM-Tools, analysis software for deriving polarization properties, such as Faraday rotation measures, from spectropolarimetric observations of linearly polarized radio sources. The software makes use of techniques such as rotation measure synthesis and QU-model fitting, along with many features to simplify and enhance the analysis of radio polarization data. RM-Tools is currently the main software that large-area polarization sky surveys such as POSSUM and VLASS deploy for science-ready data processing. The software code is freely available online and can be used with data from a wide range of telescopes.

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Cameron L. Van Eck, Cormac R. Purcell, Lerato Baidoo, Alec J. M. Thomson, Yik Ki Ma, Lindsey Oberhelman, Erik Osinga, Shannon Vanderwoude, Jennifer L. West, Shinsuke Ideguchi, Dylan M. Paré, Jane F. Kaczmarek, Tony Willis, Takuya Akahori, Craig S. Anderson, B. M. Gaensler, Shane O'Sullivan, Xiaohui Sun, Ariel D. Amaral, C. J. Riseley, Jeroen Stil, Xiang Zhang. 2026-01-27. RM-Tools: Software for Analyzing Polarized Radio Spectra. https://arxiv.org/abs/2601.20092

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