Physical Sciences and Mathematics Commons^™

Simultaneous X-Ray And Optical Observations Of An Ursae Majoris During A Low State, Paula Szkody, Edward G. Schmidt, Lidia Crosa, Robert Schommer

Edward Schmidt Publications

X-ray observations throughout the orbital cycle of AN UMa during its low state were conducted with the Einstein Observatory simultaneously with ground-based optical UBV photometry and spectroscopy. The observed low X-ray flux of 7 × 10^–13 ergs cm^–2 s^–1 is a factor of 40 below the high-state X-ray flux, and F_x/F_opt is about a factor of 50 lower than for AM Her and 2A 0311–227. There is marginal evidence for an X-ray eclipse coincident with an optical minimum and for increased X-ray flux at magnetic phase 0.4 which does not correlate with any optical …