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Title: 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 Δ V< −11 magnitude flare observed as part of the ASAS-SN survey. Optical and infrared spectroscopy indicate a spectral type of L0 with strong H α 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{sup −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 × 10{sup 33} erg (corresponding to a total thermal energy of at least E {sub tot} > 3.7 × 10{sup 34} 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.

Authors:
 [1]; ;  [2];  [3]; ; ;  [4];  [5]; ;  [6];  [7]
  1. Leibniz-Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, D-14482, Potsdam (Germany)
  2. Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)
  3. Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015 (United States)
  4. Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States)
  5. Núcleo de Astronomía de la Facultad de Ingenierá, Universidad Diego Portales, Av. Ejército 441, Santiago (Chile)
  6. Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)
  7. Kavli Institute for Astronomy and Astrophysics, Peking University, Yi He Yuan Road 5, Hai Dian District, Beijing 100871 (China)
Publication Date:
OSTI Identifier:
22654227
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 828; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CLASSIFICATION; DWARF STARS; INFRARED SPECTRA; MASS; NEAR INFRARED RADIATION; OPTICAL SPECTROMETERS; STARS; STELLAR FLARES; SUPERNOVAE; VISIBLE RADIATION

Citation Formats

Schmidt, Sarah J., Shappee, Benjamin J., Seibert, Mark, Gagné, Jonathan, Stanek, K. Z., Holoien, Thomas W.-S., Kochanek, C. S., Prieto, José L., Chomiuk, Laura, Strader, Jay, and Dong, Subo, E-mail: sjschmidt@aip.de. ASASSN-16ae: A POWERFUL WHITE-LIGHT FLARE ON AN EARLY-L DWARF. United States: N. p., 2016. Web. doi:10.3847/2041-8205/828/2/L22.
Schmidt, Sarah J., Shappee, Benjamin J., Seibert, Mark, Gagné, Jonathan, Stanek, K. Z., Holoien, Thomas W.-S., Kochanek, C. S., Prieto, José L., Chomiuk, Laura, Strader, Jay, & Dong, Subo, E-mail: sjschmidt@aip.de. ASASSN-16ae: A POWERFUL WHITE-LIGHT FLARE ON AN EARLY-L DWARF. United States. doi:10.3847/2041-8205/828/2/L22.
Schmidt, Sarah J., Shappee, Benjamin J., Seibert, Mark, Gagné, Jonathan, Stanek, K. Z., Holoien, Thomas W.-S., Kochanek, C. S., Prieto, José L., Chomiuk, Laura, Strader, Jay, and Dong, Subo, E-mail: sjschmidt@aip.de. 2016. "ASASSN-16ae: A POWERFUL WHITE-LIGHT FLARE ON AN EARLY-L DWARF". United States. doi:10.3847/2041-8205/828/2/L22.
@article{osti_22654227,
title = {ASASSN-16ae: A POWERFUL WHITE-LIGHT FLARE ON AN EARLY-L DWARF},
author = {Schmidt, Sarah J. and Shappee, Benjamin J. and Seibert, Mark and Gagné, Jonathan and Stanek, K. Z. and Holoien, Thomas W.-S. and Kochanek, C. S. and Prieto, José L. and Chomiuk, Laura and Strader, Jay and Dong, Subo, E-mail: sjschmidt@aip.de},
abstractNote = {We report the discovery and classification of SDSS J053341.43+001434.1 (SDSS0533), an early-L dwarf first discovered during a powerful Δ V< −11 magnitude flare observed as part of the ASAS-SN survey. Optical and infrared spectroscopy indicate a spectral type of L0 with strong H α 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{sup −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 × 10{sup 33} erg (corresponding to a total thermal energy of at least E {sub tot} > 3.7 × 10{sup 34} 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.},
doi = {10.3847/2041-8205/828/2/L22},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 828,
place = {United States},
year = 2016,
month = 9
}
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