Search Publications

X-ray activity from different types of stars

Zhang, Yong; Soria, Roberto; Bai, Yu +10 more

X-ray emission is an important indicator of stellar activity. In this paper, we study stellar X-ray activity using the XMM-Newton and LAMOST data for different types of stars. We provide a sample including 1259 X-ray-emitting stars, of which 1090 have accurate stellar parameter estimations. Our sample size is much larger than those used in previou…

The Y _SZ,Planck - Y _SZ,XMM scaling relation and its difference between cool-core and non-cool-core clusters

Zhao, Hai-Hui; Jia, Shu-Mei; Chen, Yong +3 more

We construct a sample of 70 clusters using data from XMM-Newton and Planck to investigate the Y _SZ,Planck - Y _SZ,XMM scaling relation and the cool-core influences on this relation. Y _SZ,XMM is calculated by accurately de-projected temperature and electron number density profiles derived from XMM-Newton. Y _S…

A multiwavelength view of a classical T Tauri star CV Cha

Karmakar, Subhajeet; Sharma, Saurabh; Joshi, Arti +3 more

Using long-term optical, ultraviolet (UV) and X-ray data, we present a study of a classical T Tauri star CV Cha. The V -band light curve obtained from the All Sky Automated Survey (ASAS) shows short as well as long-term variability. The short-term variability could be due to rotational modulation of CV Cha. We derive the rotational period of 3.714…

Intra-day variability of three Seyfert galaxies measured with XMM-Newton

Tripathi, Ashutosh; Gu, Min-Feng; Liao, Mai +2 more

We present and analyze the variability of three Seyfert galaxies on intra-day timescales. We have analyzed in a uniform manner the 38 longest (>30 ks) observations made for NGC 4051, MCG-06-30-15 and NGC 4151 by XMM-Newton between 2000 and 2015. The nuclei were quite active during essentially all of these observations and the overall X-ray flux…