Abstract. We Maps of the distribution of the spotted regions on the photosphere of the binary components were derived using the Maximum Entropy and Tikhonov photometric regularization criteria. Rotational modulation was observed in Hα and He  D 3 in anti-correlation with the photometric light curves. Both flares occurred at the same binary phase (0.85), suggesting that these events took place in the same active region. Simultaneous X-ray observations, performed by ASM on board RXTE, show several flare-like events, some of which correlate well with the observed optical flares. Rotational modulation in the X-ray light curve has been detected with minimum flux when the less active G5 V star was in front. A possible periodicity in the X-ray flare-like events was also found.

Abstract. ω Ori (HD 37490, HR 1934) is a Be star known to have presented variations. In order to investigate the nature and origin of its short-term and mid-term variability, a study is performed of several spectral lines (Hα, Hδ, He i 4471, 4713, 4921, 5876, 6678, C ii 4267, 6578, 6583

We present results from the 1996 Multi‐Site Continuous Spectroscopy (MUSICOS) campaign on the T Tauri star SU Aurigae. We find a 2.7‐d periodicity in the He i (587.6 nm) line, and somewhat longer, less well‐pronounced periodicities in the Balmer lines and in Na D. Our observations support the suggestion that the wind and infall signatures are out of phase on SU Aur. We present Doppler images of SU Aur that have been obtained from least‐squares deconvolved profiles. Images taken about one rotation apart show only limited overlap, in particular at low latitudes. This is due in part to limitations in signal‐to‐noise ratio, and in part to line‐profile deformations that arise from short‐lived and/or non‐surface features. The agreement at high latitudes is better and suggests that at least some longer‐lived features are present. The analysis of Stokes V profiles yields a marginal magnetic field detection during one of the phases.

The Large Optical/infrared Telescope (LOT) is a ground-based 12 m diameter optical/infrared telescope which is proposed to be built in the western part of China in the next decade. Based on satellite remote sensing data, along with geographical, logistical and political considerations, three candidate sites were chosen for ground-based astronomical performance monitoring. These sites include: Ali in Tibet, Daocheng in Sichuan and Muztagh-ata in Xinjiang. Up until now, all three sites have continuously collected data for two years. In this paper, we will introduce this site testing campaign, and present its monitoring results obtained during the period between March 2017 and March 2019.