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arXiv · 1812.00016

The JCMT Transient Survey: An Extraordinary Submillimetre Flare in the T Tauri Binary System JW 566

Steve Mairs·Bhavana Lalchand·Geoffrey C. Bower·Jan Forbrich·Graham S. Bell·Gregory J. Herczeg·Doug Johnstone·Wen-Ping Chen·Jeong-Eun Lee·Alvaro Hacar
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Abstract

The binary T Tauri system JW 566 in the Orion Molecular Cloud underwent an energetic, short-lived flare observed at submillimetre wavelengths by the SCUBA-2 instrument on 26 November 2016 (UT). The emission faded by nearly 50% during the 31 minute integration. The simultaneous source fluxes averaged over the observation are 500 +/- 107 mJy/beam at 450 microns and 466 +/- 47 mJy/beam at 850 microns. The 850 micron flux corresponds to a radio luminosity of $L_ν=8\times10^{19}$ erg/s/Hz, approximately one order of magnitude brighter (in terms of $νL_ν$) than that of a flare of the young star GMR-A, detected in Orion in 2003 at 3mm. The event may be the most luminous known flare associated with a young stellar object and is also the first coronal flare discovered at sub-mm wavelengths. The spectral index between 450 microns and 850 microns of $α= 0.11$ is broadly consistent with non-thermal emission. The brightness temperature was in excess of $6\times10^{4}$ K. We interpret this event to be a magnetic reconnection that energised charged particles to emit gyrosynchrotron/synchrotron radiation.

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Steve Mairs, Bhavana Lalchand, Geoffrey C. Bower, Jan Forbrich, Graham S. Bell, Gregory J. Herczeg, Doug Johnstone, Wen-Ping Chen, Jeong-Eun Lee, Alvaro Hacar. 2018-11-30. The JCMT Transient Survey: An Extraordinary Submillimetre Flare in the T Tauri Binary System JW 566. https://doi.org/10.3847/1538-4357%2Faaf3b1

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