我们展示了对活动双星系统原型RS Canum Venaticorum (RS CVn)高分辨率光谱的研究。我们的数据是1998年至2017年间使用不同望远镜获得的。我们利用光谱减法技术分析了色球活动指标Ca II IRT、H$_α$、Na I D$_{1}$、D$_{2}$双线、He I D$_{3}$和H$_β$。色球发射主要来自K2 IV主星,而F5 V伴星仅在少数光谱中显示出微弱的发射特征。我们在主食附近拍摄的光谱中,发现减除后的H$_α$谱线和其他活动指标存在过量的吸收特征,我们将其归因于与主星相关的类日珥物质。我们基于双星系统的几何结构估算了这些暂定日珥的尺寸极限,并研究了最强日珥的物理性质。我们探测到一次光学耀斑,其特征为He I D$_{3}$谱线发射,并伴随其他活动谱线更强的发射。该耀斑能量与在其他RS CVn型恒星上观测到的强耀斑大致相当。RS CVn的色球活动经度最常出现在系统的两个方照附近,并在观测运行之间显示出变化,这表明其活动区域正在持续演化。
英文摘要:
We present a study of high-resolution spectra of RS Canum Venaticorum (RS CVn), a prototype of active binary systems. Our data were obtained from 1998 to 2017 using different telescopes. We analyze the chromospheric activity indicators Ca II IRT, H$_α$, Na I D$_{1}$, D$_{2}$ doublet, He I D$_{3}$, and H$_β$ using a spectral subtraction technique. The chromospheric emission stems mainly from the K2 IV primary star, while the F5 V secondary star only shows weak emission features in a few of our spectra. We find excess absorption features in the subtracted H$_α$ lines and other activity indicators from spectra taken near primary eclipse, which we ascribe to prominence-like material associated with the primary star. We estimate size limits of these tentative prominences based on the geometry of the binary system, and investigate the physical properties of the strongest prominence. An optical flare, characterized by He I D$_{3}$ line emission, together with stronger emission in other activity lines, was detected. The flare energy is roughly comparable to strong flares observed on other RS CVn-type stars. The chromospherically active longitudes of RS CVn most frequently appear near the two quadratures of the system and display changes between observing runs, which indicates an ongoing evolution of its active regions.
Multi-wavelength Study of A Superflare on RS CVn-type Star HD22468 Triggered at Hard X-ray by SVOM
National Astronomical Observatories, Chinese Academy of Sciences(中国科学院国家天文台);Universite Paris Cite, CNRS, Astroparticule et Cosmologie(巴黎大学,法国国家科学研究中心,粒子与宇宙学实验室);Institute de Recherche en Astrophysique & Planetologie(天体物理与行星学研究所在);School of Astronomy and Space Science, University of Chinese Academy of Sciences(中国科学院大学天文与空间科学学院)
A Possible Stellar CME Event Associated with a Long-duration Optical Flare on the RS CVn-type Star UX Arietis
International Centre of Supernovae (ICESUN), Yunnan Key Laboratory of Supernova Research, Yunnan Observatories, Chinese Academy of Sciences(中国科学院云南天文台);Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences(中国科学院天体结构与演化重点实验室);Yunnan Observatories, Chinese Academy of Sciences(中国科学院云南天文台);School of Astronomy and Space Science, University of Chinese Academy of Sciences(中国科学院大学天文与空间科学学院)
Magnetic structure of an activated filament in a flaring active region
虽然人们对静态磁致伸缩中的磁场进行了广泛的研究,但对激活磁致伸缩中的磁场却知之甚少。本文介绍了耀斑活动区激活暗条的磁场结构的观测结果。我们研究,特别是,它的磁结构和视线流在其早期激活阶段,不久之前,它显示出旋转的迹象。我们反演了在特内里费岛VTT观测到的色球He I 10830 A三线态和光球Si I 10827 A线的Stokes轮廓。利用这些反演结果,我们提出和解释的速度和磁场的第一张地图中获得的激活灯丝,在光球和色球。在暗条的色球层中发现了多达5种不同的磁性成分,而在暗条之外,一个单一的成分就足以重现观测结果。显示向上流动的磁性部件优选地朝向细丝的中心定位,而向下流动沿着细丝的外围集中。此外,向上流动的气体与相对于光球的极性相反的磁性配置相关联,而向下流动的气体与相同极性的配置相关联。激活的灯丝具有相当复杂的结构。尽管如此,在正常配置中,它与磁通绳兼容,尽管是扭曲的磁通绳。观测结果最好用上升的通量绳来解释,其中一部分细丝材料仍然稳定地储存(向上流动的材料,随着场上升),而另一部分不再稳定地储存并沿着场线向下流动。
Doppler-shifted Signatures in the Chromospheric Line Profiles of II Pegasi
Yunnan Observatories, Chinese Academy of Sciences(中国科学院云南天文台);Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences(中国科学院天体结构与演化重点实验室);International Centre of Supernovae, Yunnan Key Laboratory(超新星国际中心,云南省重点实验室);School of Astronomy and Space Science, University of Chinese Academy of Sciences(中国科学院大学天文与空间科学学院)
Multiwavelength Campaign Observations of a Young Solar-type Star, EK Draconis. III. Comparison between Starspot Mapping, Zeeman Doppler Imaging, and Multiwavelength Variability
Hitotsubashi University(一桥大学);The University of Tokyo(东京大学);The Hakubi Center for Advanced Research, Kyoto University(京都大学博雅研究高级中心);Department of Physics, Kyoto University(京都大学物理学系);NASA Goddard Space Flight Center(美国宇航局戈达德太空飞行中心);Department of Physics, The Catholic University of America(美利坚天主教大学物理学系);Division of Science, National Astronomical Observatory of Japan, NINS(日本国立天文台科学部);Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, CNRS, CNES(图卢兹大学、法国国家科学研究中心、法国国家空间研究中心天体物理与行星学研究所在);Department of Physics, American University(美国大学物理学系)