Observation of a possible superflare on Proxima Centauri
arXiv:1904.06875 · doi:10.1093/mnrasl/slz054
Abstract
We report the observation on UT 2017.07.01 of an unusually powerful flare detected in near-infrared continuum photometry of Proxima Centauri. During a campaign monitoring the star for possible exoplanet transits, we identified an increase in Sloan i' flux leading to an observed peak at BJD 2457935.996 that was at least 10\% over pre-flare flux in this band. It was followed by a 2-component rapid decline in the first 100 seconds that became a slower exponential decay with time constant of 1350 seconds. A smaller flare event 1300 seconds after the first added an incremental peak flux increase of 1% of pre-flare flux. Since the onset of the flare was not fully time-resolved at a cadence of 62 seconds, its actual peak value is unknown but greater than the time-average over a single exposure of 20 seconds. The i' band is representative of broad optical and near-IR continuum flux over which the integrated energy of the flare is 100 times the stellar luminosity. This meets the criteria that established the concept of superflares on similar stars. The resulting implied ultraviolet flux and space weather could have had an extreme effect on the atmospheres of planets within the star's otherwise-habitable zone.
5 pages, 2 figures
References in corpus (6)
- The Transiting Exoplanet Survey Satellite
- A terrestrial planet candidate in a temperate orbit around Proxima Centauri
- Superflare occurrence and energies on G-, K- and M-type dwarfs
- MOST Observations of our Nearest Neighbor: Flares on Proxima Centauri
- Reduced Diversity of Life Around Proxima Centauri and TRAPPIST-1
- Detection of a giant white-light flare on an L2.5 dwarf with the Next Generation Transit Survey