<正>We monitored the light curves of 22 weak-line T Tauri stars (WTTSs) discovered among the X-ray sources in the field of the Taurus-Auriga cloud. For 12 of th
By means of a population synthesis code, we investigate the Mira variables. Their birth rate (over 0.65yr-1) and their number (~ 130000) in the Galaxy are estima
We present an atlas of a group of bright stars in the range of spectral classes F-G and luminosity classes Ⅰ-Ⅴ.The spectra were obtained with spectral resolut
Quantities characterizing temporal property, e.g., power density, co-herence, and time lag, can be defined and calculated directly in the time domain without us