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Title: MOST OBSERVATIONS OF OUR NEAREST NEIGHBOR: FLARES ON PROXIMA CENTAURI

Abstract

We present a study of white-light flares from the active M5.5 dwarf Proxima Centauri using the Canadian microsatellite Microvariability and Oscillations of STars . Using 37.6 days of monitoring data from 2014 to 2015, we have detected 66 individual flare events, the largest number of white-light flares observed to date on Proxima Cen. Flare energies in our sample range from 10{sup 29} to 10{sup 31.5} erg. The flare rate is lower than that of other classic flare stars of a similar spectral type, such as UV Ceti, which may indicate Proxima Cen had a higher flare rate in its youth. Proxima Cen does have an unusually high flare rate given its slow rotation period, however. Extending the observed power-law occurrence distribution down to 10{sup 28} erg, we show that flares with flux amplitudes of 0.5% occur 63 times per day, while superflares with energies of 10{sup 33} erg occur ∼8 times per year. Small flares may therefore pose a great difficulty in searches for transits from the recently announced 1.27 M {sub ⊕} Proxima b, while frequent large flares could have significant impact on the planetary atmosphere.

Authors:
 [1];  [2];  [3];  [4];  [5]
  1. Department of Physics and Astronomy, Western Washington University, 516 High Street, Bellingham, WA 98225 (United States)
  2. Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)
  3. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
  4. Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada)
  5. Department of Mathematics, Physics and Geology, Cape Breton University, 1250 Grand Lake Road, Sydney, NS B1P 6L2 (Canada)
Publication Date:
OSTI Identifier:
22654208
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 829; 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; AMPLITUDES; DISTRIBUTION; DWARF STARS; MASS; OSCILLATIONS; PLANETARY ATMOSPHERES; ROTATION; STARS; VISIBLE RADIATION

Citation Formats

Davenport, James R. A., Kipping, David M., Sasselov, Dimitar, Matthews, Jaymie M., and Cameron, Chris. MOST OBSERVATIONS OF OUR NEAREST NEIGHBOR: FLARES ON PROXIMA CENTAURI. United States: N. p., 2016. Web. doi:10.3847/2041-8205/829/2/L31.
Davenport, James R. A., Kipping, David M., Sasselov, Dimitar, Matthews, Jaymie M., & Cameron, Chris. MOST OBSERVATIONS OF OUR NEAREST NEIGHBOR: FLARES ON PROXIMA CENTAURI. United States. doi:10.3847/2041-8205/829/2/L31.
Davenport, James R. A., Kipping, David M., Sasselov, Dimitar, Matthews, Jaymie M., and Cameron, Chris. 2016. "MOST OBSERVATIONS OF OUR NEAREST NEIGHBOR: FLARES ON PROXIMA CENTAURI". United States. doi:10.3847/2041-8205/829/2/L31.
@article{osti_22654208,
title = {MOST OBSERVATIONS OF OUR NEAREST NEIGHBOR: FLARES ON PROXIMA CENTAURI},
author = {Davenport, James R. A. and Kipping, David M. and Sasselov, Dimitar and Matthews, Jaymie M. and Cameron, Chris},
abstractNote = {We present a study of white-light flares from the active M5.5 dwarf Proxima Centauri using the Canadian microsatellite Microvariability and Oscillations of STars . Using 37.6 days of monitoring data from 2014 to 2015, we have detected 66 individual flare events, the largest number of white-light flares observed to date on Proxima Cen. Flare energies in our sample range from 10{sup 29} to 10{sup 31.5} erg. The flare rate is lower than that of other classic flare stars of a similar spectral type, such as UV Ceti, which may indicate Proxima Cen had a higher flare rate in its youth. Proxima Cen does have an unusually high flare rate given its slow rotation period, however. Extending the observed power-law occurrence distribution down to 10{sup 28} erg, we show that flares with flux amplitudes of 0.5% occur 63 times per day, while superflares with energies of 10{sup 33} erg occur ∼8 times per year. Small flares may therefore pose a great difficulty in searches for transits from the recently announced 1.27 M {sub ⊕} Proxima b, while frequent large flares could have significant impact on the planetary atmosphere.},
doi = {10.3847/2041-8205/829/2/L31},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 829,
place = {United States},
year = 2016,
month =
}
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