As a rule has a persistent high state; five drops by two to more than three magnitudes have been registered and a twelve year interval of irregular variations at intermediate magnitudes. According to [B.Warner, M.Cropper, MN 206, N2, 261, 1984.] there are slow variations in brightness by 0.15m on a time scale of ~1 day. They are superimposed by variations with the orbital period P orb (Max = 2444749.9866 + 0.140239d*E) and with amplitude up to 0.15m. These variations in their turn are superimposed by the others: with P = 794.38s and the amplitude from 0.03m up to 0.15m (Max = 2444750.00404 + 0.009194215d*E and (sometimes) with P = 849.8s and a twice smaller amplitude (Max = 2444750.00350 + 0.00983588d*E). Besides there are rapid brightness variations on time scales 10 - 100s by 0.10m - 0.20m, and high frequency flickering by 0.05m. According to [W.R.Penning, ApJ 289, 300, 1985.], the period of X-ray pulses associated with the rotation of the compact object is 12.5 minutes.
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