ASASSN-16ae: A Powerful White-light Flare on an Early-L Dwarf
Abstract
We report the discovery and classification of SDSS J053341.43+001434.1 (SDSS0533), an early-L dwarf first discovered during a powerful ΔV < -11 magnitude flare observed as part of the ASAS-SN survey. Optical and infrared spectroscopy indicate a spectral type of L0 with strong Hα emission and a blue NIR spectral slope. Combining the photometric distance, proper motion, and radial velocity of SDSS0533 yields three-dimensional velocities of (U, V, W) = (14 ± 13, -35 ± 14, -94 ± 22) km s-1, indicating that it is most likely part of the thick disk population and probably old. The three detections of SDSS0533 obtained during the flare are consistent with a total V-band flare energy of at least 4.9 × 1033 erg (corresponding to a total thermal energy of at least E tot > 3.7 × 1034 erg), placing it among the strongest detected M dwarf flares. The presence of this powerful flare on an old L0 dwarf may indicate that stellar-type magnetic activity persists down to the end of the main sequence and on older ML transition dwarfs.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2016
- DOI:
- 10.3847/2041-8205/828/2/L22
- arXiv:
- arXiv:1605.04313
- Bibcode:
- 2016ApJ...828L..22S
- Keywords:
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- brown dwarfs;
- stars: chromospheres;
- stars: flare;
- stars: individual: SDSS J053341.43+001413.1;
- stars: low-mass;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 7 pages, 3 tables, 2 figures