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arXiv · 2401.07609

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

Samrat Ghosh·Soumen Mondal·Santosh Joshi·Sneh Lata·Rajib Kumbhakar
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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. %Multi-wavelength studies on star-forming regions help to understand the census of PMS stars, their formation process, and the interaction of expanding H II regions harboring massive stars with their natal molecular clouds. 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 $\sim$ 3 days. We found two flare events in TESS sector 43 data for this BD and estimated the flared energies as $4.59\times10^{35}$ erg and $2.64\times10^{36}$ erg, which sit in the superflare range.

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Samrat Ghosh, Soumen Mondal, Santosh Joshi, Sneh Lata, Rajib Kumbhakar. 2024-01-15. Photometric Variability of Low Mass Stars and Brown Dwarfs in IC~348 and Taurus Star-Forming Regions. https://arxiv.org/abs/2401.07609

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