IRC-10443：一个多周期SRa变星和AGB星的长次级周期性质
IRC-10443: a multi-periodic SRa variable and the nature of long secondary periods in AGB stars
摘要：
我们获得了IRC-10443在两年中分布的85个不同夜晚的BVIc光度，以及低分辨率绝对光度和高分辨率中阶梯光谱。我们的数据表明，IRC-10443是一个SRa变星，以前从未对其进行过任何详细的研究，其特征是Delta（B）=1.27，Delta（V）=1.14和Delta（I）=0.70等振幅，平均值<B>=13.75，<V>=11.33和<Ic>=6.18等。同时存在两个强周期：主波为85.5（+/-0.2）天，次波为620（+/-15）天，两者都是正弦曲线形状，半振幅分别为Delta（V）=0.41和0.20 mag。IRC-10443是一颗M7 III型恒星，平均日心视向速度为-28 km/s，红化E（B-V）=0.87，其中三分之一来自星周。同样的0.5千秒差距的距离是从应用适当的周期光度关系到主周期和副周期。长的二次周期导致的正弦变化的颜色的0.13等半振幅的V-IC，IRC-10443是最蓝的最大和最红的最小值，并与相关的变化，在有效温度和半径的85 K和6%，分别。这种颜色的行为支持AGB星中仍然神秘的长次级周期的脉动性质。
英文摘要：
We obtained BVIc photometry of IRC-10443 on 85 different nights distributed over two years, and in addition low resolution absolute spectro- photometry and high resolution Echelle spectroscopy. Our data show that IRC-10443, which was never studied before in any detail, is a SRa variable, characterized by Delta(B)=1.27, Delta(V)=1.14 and Delta(I)=0.70 mag amplitudes and mean values <B>=13.75, <V>=11.33 and <Ic>=6.18 mag. Two strong periodicities are simultaneously present: a principal one of 85.5 (+/-0.2) days, and a secondary one of 620 (+/-15) days, both sinusoidal in shape, and with semi-amplitudes Delta(V)=0.41 and 0.20 mag, respectively. IRC-10443 turns out to be a M7III star, with a mean heliocentric radial velocity -28 km/s and reddened by E(B-V)=0.87, a third of which of circumstellar origin. The same 0.5 kpc distance is derived from application of the appropriate period-luminosity relations to both the principal and the secondary periods. The long secondary period causes a sinusoidal variation in color of 0.13 mag semi-amplitude in V-Ic, with IRC-10443 being bluest at maximum and reddest at minimum, and with associated changes in effective temperature and radius of 85 K and 6%, respectively. This behavior of colors argues in favor of a pulsation nature for the still mysterious long secondary periods in AGB stars.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
