论文标题
星形点，色球发射线和零量主要恒星的耀斑
Starspots, chromospheric emission lines, and flares of zero-age main-sequence stars
论文作者
论文摘要
零年龄的主要序列（ZAMS）恒星被认为具有巨大的星形，并且由于其强烈的表面磁场而显示出强的色球发射线。我们讨论了扎姆斯恒星的发电机活性，相对于由星形恒星引起的周期光变化以及色球发射线的强度。从IC 2391中的$ 33 $ ZAMS星和IC 2602的光曲线从\ textit {tess}光度数据获得。光曲线可以分为以下四个类别：单频，可能的形状更换器，打击器和复杂的变异性。光曲线的幅度为$ 0.001-0.145 \，\ Mathrm {mag} $，类似于pleiades中的Zams星星。星点覆盖范围为$ 0.1-21 \％$。我们发现，在IC 2391，IC 2602和Pleiades群集中，ZAMS恒星的光变化和Ca \，\发射型{II}发射线强度与最高的超级荧光星和两个比太阳明星大的订单一样大，并且位于超级荧光大量的扩展上。这些结果表明，Superflare星星将太阳的特性与年龄段$ 30 $至$ 120 \，\ Mathrm {Myr} $之间的ZAMS星星联系起来。光曲线中具有单个频率或可能形状变化的ZAMS恒星往往具有较大的光变化，表明较大的斑点覆盖率和饱和的Ca \，\ \ \ \ \ \ \ \ \ \ \ \ assissionType {ii}发射线强度。具有节拍或复杂变异性的ZAMS星的斑点覆盖范围很小，并且淡淡的Ca \，\发射类型{II}发射线。我们还检测到\ textIt {tess} $ 12 $ ZAMS星星的$ 21 $耀斑在IC 2391和IC 2602中，其中大多数恒星都饱和了色层CA \，\ sumissionType {II}发射线。耀斑的能量估计为$ \ sim 10^{33} -10^{35} \，\ mathrm {erg} $，与超弹力的能量相媲美。
Zero-age main-sequence (ZAMS) stars are considered to have enormous starspots and show strong chromospheric emission lines because of their strong surface magnetic field. We discuss the dynamo activities of ZAMS stars with respect to their periodic light variation caused by a starspot and with respect to the strength of the chromospheric emission lines. The light curves of $33$ ZAMS stars in IC 2391 and IC 2602 were obtained from \textit{TESS} photometric data. The light curves can be grouped into the following four categories: single frequency, possible shape changer, beater, and complex variability. The amplitudes of the light curves are $0.001-0.145\,\mathrm{mag}$, similar to those of ZAMS stars in Pleiades. The starspot coverages are $0.1-21\%$. We found that the light variations and Ca\,\emissiontype{II} emission line strength of ZAMS stars in IC 2391, IC 2602, and the Pleiades cluster are as large as those of the most active superflare stars and two orders larger than those of the Sun, and are located on the extensions of the superflare stars. These results suggest that superflare stars link the properties of the Sun to those of the ZAMS stars of ages between $30$ and $120\,\mathrm{Myr}$. ZAMS stars with a single frequency or possible shape change in the light curve tend to have both large light variation, indicating large spot coverage, and saturated Ca\,\emissiontype{II} emission line strength. ZAMS stars with beat or complex variability have small spot coverage and a faint Ca\,\emissiontype{II} emission line. We also detected $21$ flares in the \textit{TESS} light curves of $12$ ZAMS stars in IC 2391 and IC 2602, where most of these stars have saturated chromospheric Ca\,\emissiontype{II} emission lines. The energies of the flares are estimated to be $\sim 10^{33}-10^{35}\,\mathrm{erg}$, which is comparable with the energy of a superflare.
