Bulletin de la Société Royale des Sciences de Liège Bulletin de la Société Royale des Sciences de Liège -  Volume 93 - Année 2024  No 2 - Proceeedings of the 3rd BINA Workshop on the Scientific Potential of the Indo-Belgian Cooperation 

Photometric Variability of Low Mass Stars and Brown Dwarfs in IC 348 and Taurus Star-Forming Regions

Samrat Ghosh
S. N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700106, India. Corresponding author: samrat687@gmail.com
Soumen Mondal
S. N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700106, India. Corresponding author: soumen.mondal@bose.res.in
Santosh Joshi
Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Nainital-263002, India
Sneh Lata
Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Nainital-263002, India
Rajib Kumbhakar
S. N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700106, India

Abstract

Low-mass stars belonging to the M spectral type are the most numerous stars in our Galaxy, amounting to about two-thirds in number, and are found at the bottom of the main sequence in the H-R diagram. Photometric studies of low-mass stars, including brown dwarfs (Bds), provide several important evolutions of their atmosphere, magnetic flares and chromospheric activity. This paper highlights a few interesting results from our optical I-band observations of 2MASS J03435638+3209591 in the young star-forming IC 348 region and three BDs in Taurus star-forming regions using ground-based telescopes as well as a space-based telescope. We estimated the fast periodicities in the range of 1.5 to 3 hours in Taurus BDs. Furthermore, using the long-term photometry from the Transiting Exoplanet Survey Satellite (TESS), we have conducted a time-resolved variability analysis of CFHT-BD-Tau 4. The periodogram analysis of TESS data reveals an orbital period of ∼ 3 days. We found two flare events in TESS sector 43 data for this BD and estimated the flared energies as 4.59×1035 erg and 2.64×1036 erg, which sit in the superflare range.

Keywords : star forming regions, brown dwarfs, very low mass stars, M dwarfs, flares

To cite this article

Samrat Ghosh, Soumen Mondal, Santosh Joshi, Sneh Lata & Rajib Kumbhakar, «Photometric Variability of Low Mass Stars and Brown Dwarfs in IC 348 and Taurus Star-Forming Regions», Bulletin de la Société Royale des Sciences de Liège [En ligne], Volume 93 - Année 2024, No 2 - Proceeedings of the 3rd BINA Workshop on the Scientific Potential of the Indo-Belgian Cooperation, 623-635 URL : https://popups.uliege.be/0037-9565/index.php?id=11817.