MAXI/GSC detection of an active state of the RS CVn type star UX Ari

We report an X-ray detection with MAXI/GSC from the position consistent with the RS CVn type variable UX Ari. The flux increasing was observed from 2011-04-26 09:36 (UT) (= MJD 55677.414) and the active state lasted at least to the latest transit starting at 2011-04-27 05:42 (UT) (= MJD 55678.238). The active state seems to comprise multiple flares, and the flux maximum was observed at the transit starting from 2011-04-27 01:13 (UT) (= MJD 55678.051) with the preliminary flux of about 130 +-30 mCrab (1-sigma statistical error) in the 4-10 keV band.