We present the first detailed X-ray study and simultaneous optical observations of active fast rotating star FR Cnc. The spectra are found to be explained by two-temperature plasma model with temperature cool hot components 0.34 1.1 keV, respectively. light curve in 0.5–2.0 keV energy band is rotationally modulated degree rotational modulation $$\sim$$ 17%. have also that anti-correlated colour...

We suggest that the radio emission from the dwarf nova SS Cyg during outburst comes from magnetic activity that formed a corona (similar to coronae found in magnetically active stars), rather than from jets. We base our claim on the recent results of Laor & Behar, who found that when the ratio between radio and X-ray flux of accretion disks in radio-quiet quasars is as in active stars, Lr/Lx . ...