V746 Cas is known to be a triple system composed of a close binary with an alternatively reported period of either 25.4d or 27.8d and a third component in a 62000d orbit. The object was also reported to exhibit multiperiodic light variations with periods from 0.83d to 2.50d, on the basis of which it was classified as a slowly pulsating B star. Interest in further investigation of this system was raised by the detection of a variable magnetic field. Analysing spectra from four instruments, earlier published radial velocities, and several sets of photometric observations, we arrived at the following conclusions: (1) The optical spectrum is dominated by the lines of the B-type primary (Teff1~16500(100) K), contributing 70% of the light in the optical region, and a slightly cooler B tertiary (Teff3~13620(150) K). The lines of the low-mass secondary are below our detection threshold; we estimate that it could be a normal A or F star. (2) We resolved the ambiguity in the value of the inner binary period and arrived at a linear ephemeris of T_super.conj.=HJD 2443838.78(81)+25.41569(42)xE. (3) The intensity of the magnetic field undergoes a~sinusoidal variation in phase with one of the known photometric periods, namely 2.503867(19)d, which we identify with the rotational period of the tertiary. (4) The second photometric 1.0649524(40)d period is identified with the rotational period of the B-type primary, but this interpretation is much less certain and needs further verification. (5) If our interpretation of photometric periods is confirmed, the classification of the object as a slowly pulsating B star should be revised. (6) Applying an N-body model to different types of available observational data, we constrain the orbital inclination of the inner orbit to ~60 deg to 85 deg even in the absence of eclipses, and estimate the probable properties of the triple system and its components.
Detection of dark companions via the combination of eclipse timing variation, Hipparcos and/or Gaia astrometry: the cases of V Puppis and CY Ari
State Key Laboratory of Dark Matter Physics, Tsung-Dao Lee Institute & School of Physics and Astronomy, Shanghai Jiao Tong University（暗物质物理国家重点实验室、李政道理论与计算科学研究所及物理与天文学院，上海交通大学）；Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences（光学天文重点实验室，中国科学院国家天文台）；Institute for Frontiers in Astronomy and Astrophysics, Beijing Normal University（前沿天体物理研究院，北京师范大学）；Shandong Key Laboratory of Space Environment and Exploration Technology, Institute of Space Sciences, School of Space Science and Technology, Shandong University（空间环境与探测技术山东省重点实验室、空间科学学院及空间科学与技术学院，山东大学）
Acoustic oscillations in the field-free, gravitationally stratified Acoustic oscillations in the field-free, gravitationally stratified cavities under solar bipolar magnetic canopies
Backtracking Bipolar Magnetic Regions to their emergence: Two groups and their implication in the tilt measurements
Indian Institute of Technology (Banaras Hindu University)（印度理工学院（贝拿勒斯印度教大学））；Southwest Research Institute（西南研究所）；Indian Institute of Astrophysics（印度天体物理研究所）；IISER Kolkata（加尔各答印度科学教育研究所）
