1998A&A...338..988Z

The flickering activity in the recurrent nova and symbiotic star T CrB is investigated using light curves taken in the Johnson U band. In order to be able to compare the results with those of other CVs the contribution of the red giant secondary is first estimated and subtracted. It is found to be ≃10% on the average. The U band flux varies considerably over long time scales, but the ratio of the flux of the flickering light source and the quiet part of the primary remains constant. This is in contrast to the behaviour of dwarf novae around the outburst cycle. A wavelet analysis reveils a remarkable constancy of the distribution of flickering energy among different time scales as compared to other CVs. With the exception of the particular, not well understood feature that the activity can disappear temporarily, flickering in T CrB is on the whole indistinguishable from that in normal cataclysmic variables, in particular in classical novae, although the geometrical dimensions are very different. This is one more indication that the vicinity of a white dwarf, being of similar size in all CVs independent of their absolute dimensions, is the site of the flickering.