Fast photometric variability of very low mass stars in IC 348: detection of superflare in an M dwarf
Abstract
We present here optical I-band photometric variability study down to ≃19 mag of a young (∼2-3 Myr) star-forming region IC 348 in the Perseus molecular cloud. We aim to explore the fast rotation (in the time-scales of hours) in very low-mass stars including brown dwarfs (BDs). From a sample of 177 light curves using our new I-band observations, we detect new photometric variability in 22 young M dwarfs including 6 BDs, which are bonafide members in IC 348 and well characterized in the spectral type of M dwarfs. Out of 22 variables, 11 M dwarfs including one BD show hour-scale periodic variability in the period range 3.5-11 h and rest are aperiodic in nature. Interestingly, an optical flare is detected in a young M2.75 dwarf in one night data on 2016 December 20. From the flare light curve, we estimate the emitted flared energy of 1.48 × 1035 erg. The observed flared energy with an uncertainty of tens of per cent is close to the superflare range (∼1034 erg), which is rarely observed in active M dwarfs.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- January 2021
- DOI:
- 10.1093/mnras/staa3574
- arXiv:
- arXiv:2011.07156
- Bibcode:
- 2021MNRAS.500.5106G
- Keywords:
-
- methods: observational;
- stars: atmospheres;
- brown dwarfs;
- stars: flare;
- stars: low-mass;
- stars: variables: general;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 12 pages, 5 figures