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arXiv · 1010.1277

Identification of strong photometric activity in the components of LHS 1070

L. A. Almeida·F. Jablonski·E. Martioli
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Abstract

Activity in low-mass stars is an important ingredient in the evolution of such objects. Fundamental physical properties such as age, rotation, magnetic field are correlated with activity. Aims: We show that two components of the low-mass triple system LHS 1070 exhibit strong flaring activity. We identify the flaring components and obtained an improved astrometric solution for the LHS 1070 A/(B+C) system. Methods: Time-series CCD observations were used to monitor LHS 1070 in the B and I_C bands. H-band data were used to obtain accurate astrometry for the LHS 1070 A/(B+C) system. Results: We have found that two components of the triple system LHS 1070 exhibit photometric activity. We identified that components A and B are the flaring objects. We estimate the total energy, ~2.0 x 10^{33} ergs, and the magnetic field strength, ~5.5 kG, of the flare observed in LHS 1070 B. This event is the largest amplitude, \Delta B > 8.2 mag, ever observed in a flare star.

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L. A. Almeida, F. Jablonski, E. Martioli. 2010-10-06. Identification of strong photometric activity in the components of LHS 1070. https://doi.org/10.1051/0004-6361/201014219

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