We present the discovery of an extreme flaring event from Proxima Cen by the Australian Square Kilometre Array Pathfinder (ASKAP), Atacama Large Millimeter/submillimeter Array (ALMA), Hubble Space Telescope (HST), Transiting Exoplanet Survey Satellite (TESS), and the du Pont Telescope that occurred on 2019 May 1. In the millimeter and FUV, this flare is the brightest ever detected, brightening by a factor of >1000 and >14,000 as seen by ALMA and HST, respectively. The millimeter and FUV continuum emission trace each other closely during the flare, suggesting that millimeter emission could serve as a proxy for FUV emission from stellar flares and become a powerful new tool to constrain the high-energy radiation environment of exoplanets. Surprisingly, optical emission associated with the event peaks at a much lower level with a time delay. The initial burst has an extremely short duration, lasting for <10 s. Taken together with the growing sample of millimeter M dwarf flares, this event suggests that millimeter emission is actually common during stellar flares and often originates from short burst-like events.

我们展示了澳大利亚平方公里阵列探路者 (ASKAP)、阿塔卡马大型毫米/亚毫米阵列 (ALMA)、哈勃太空望远镜 (HST)、凌日系外行星勘测卫星 (TESS) 和杜邦望远镜发生在 2019 年 5 月 1 日。在毫米和 FUV 中，这种耀斑是有史以来探测到的最亮的耀斑，分别由 ALMA 和 HST 观察到的亮度提高了 >1000 和 >14,000。毫米波和 FUV 连续谱发射在耀斑期间相互追踪，表明毫米波发射可以作为恒星耀斑 FUV 发射的代表，成为约束系外行星高能辐射环境的有力新工具。令人惊讶的是，与该事件相关的光发射在具有时间延迟的低得多的水平上达到峰值。初始爆发持续时间极短，持续<10 秒。连同不断增长的毫米 M 矮耀斑样本一起，该事件表明毫米辐射实际上在恒星耀斑期间很常见，并且通常源自类似短爆发的事件。