LO Peg: surface differential rotation, flares, and spot-topographic evolution
Makaleler > Tam Makale · 2016
Yazarlar: Subhajeet Karmakar, J. C. Pandey, I. S. Savanov, G. Taş, S. B. Pandey, K. Misra, S. Joshi, E. S. Dmitrienko, T. Sakamoto, N. Gehrels, T. Okajima
Monthly Notices of the Royal Astronomical Society, Uluslararası, Wos, 2016, cilt 459, ss 3112-3129
DOI: 10.1093/mnras/stw855
Özet
Using the wealth of ∼24 yr multiband data, we present an in-depth study of the star-spot cycles, surface differential rotations (SDR), optical flares, evolution of star-spot distributions, and coronal activities on the surface of young, single, main-sequence, ultrafast rotator LO Peg.From the long-term V-band photometry, we derive rotational period of LO Peg to be 0.4231 ± 0.0001 d.Using the seasonal variations on the rotational period, the SDR pattern is investigated, and shows a solar-like pattern of SDR.A cyclic pattern with period of ∼2.7 yr appears to be present in rotational period variation.During the observations, 20 optical flares are detected with a flare frequency of ∼1 flare per two days and with flare energy of ∼10 31-34 erg.The surface coverage of cool spots is found to be in the range of ∼9-26 per cent.It appears that the high-and low-latitude spots are interchanging their positions.Quasi-simultaneous observations in X-ray, UV, and optical photometric bands show a signature of an excess of X-ray and UV activities in spotted regions.