Mining the time axis with TRON. II. MeerKAT detects a stellar radio flare from a distant RS CVn candidate

Oleg M. Smirnov; Aaron Golden; Talon Myburgh; Buntu Ngcebetsha; Cyril Tasse; Ian Heywood; Athanaseus J. T. Ramaila; Mark A. Thompson; Jonathan S. Kenyon; Simon J. Perkins; James Dawson; Hertzog L. Bester; Joe S. Bright; Nadeem Oozeer; Victoria G. G. Samboco; Isaac Sihlangu; Carmen Choza

arXiv · 2501.09489

Mining the time axis with TRON. II. MeerKAT detects a stellar radio flare from a distant RS CVn candidate

Oleg M. Smirnov·Aaron Golden·Talon Myburgh·Buntu Ngcebetsha·Cyril Tasse·Ian Heywood·Athanaseus J. T. Ramaila·Mark A. Thompson·Jonathan S. Kenyon·Simon J. Perkins·James Dawson·Hertzog L. Bester·Joe S. Bright·Nadeem Oozeer·Victoria G. G. Samboco·Isaac Sihlangu·Carmen Choza

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Abstract

Medium-timescale (minutes to hours) radio transients are a relatively unexplored population. The wide field-of-view and high instantaneous sensitivity of instruments such as MeerKAT provides an opportunity to probe this class of sources, using image-plane detection techniques. The previous letter in this series describes our project and associated TRON pipeline designed to mine archival MeerKAT data for transient and variable sources. In this letter, we report on a new transient, a radio flare, associated with Gaia DR3 6865945581361480448, a G type star, whose parallax places it at a distance of 1334 pc. Its duration and high degree of circular polarization suggests electron cyclotron maser instability as the mechanism, consistent with an RS CVn variable.

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Oleg M. Smirnov, Aaron Golden, Talon Myburgh, Buntu Ngcebetsha, Cyril Tasse, Ian Heywood, Athanaseus J. T. Ramaila, Mark A. Thompson, Jonathan S. Kenyon, Simon J. Perkins, James Dawson, Hertzog L. Bester, Joe S. Bright, Nadeem Oozeer, Victoria G. G. Samboco, Isaac Sihlangu, Carmen Choza. 2025-01-16. Mining the time axis with TRON. II. MeerKAT detects a stellar radio flare from a distant RS CVn candidate. https://arxiv.org/abs/2501.09489

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