Evolution of spiral shocks in U Gem during outburst
نویسنده
چکیده
Time resolved spectroscopic observations of U Gem during its March 2000 outburst show strong spiral shocks in the accretion disk. During the plateau at maximum brightness the spiral shocks contribute ∼14% to the total He II flux. The two arms of the spiral show a distinctly different evolution during the outburst and decline, which indicates an asymmetric evolution in the disk.
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