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arXiv · 2609.37224

Multi-wavelength polarization degree dependence of Mrk 421 for different particle energy distributions

Hritwik Bora·Ranjeev Misra·Rupjyoti Gogoi
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Abstract

We report on the constraints obtained from the multi-wavelength polarization degree and energy spectra measurements for the High Synchrotron Peaked Blazar (HBL) source Mrk 421 using different forms of the electron energy distribution. We find that the optical and X-ray data are consistent with the electron energy distribution being a broken power-law (BPL) or other distributions, with all electrons experiencing the same magnetic field configuration. This is in contrast to other HBL sources like the Mrk 501, where, for the BPL distribution, the X-ray producing higher energy electrons need to exist in a more ordered magnetic field environment than the optical producing lower energy ones. This is because the break energy of the spectrum produced by the BPL distribution for Mrk 421 lies below the IXPE energy band. We discuss the implications of the findings.

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Hritwik Bora, Ranjeev Misra, Rupjyoti Gogoi. 2026-09-29. Multi-wavelength polarization degree dependence of Mrk 421 for different particle energy distributions. https://arxiv.org/abs/2609.37224

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