SIMBAD references

We present the results of coordinated photometric/spectroscopic observations on MWC 560 in search for time resolved spectral changes correlated with the large amplitude photometric flickering. The magnetic binary was observed in 1993 and 1994, during the quasi-stationary regime of its mass-ejection activity (ejection velocity ∼1300km/s). In spite of observed flickering amplitudes of ∼0.35mag in B and ∼0.2mag in V, no significant change (at a few % level) in intensity and profile was observed both for the narrow emission lines and their deep, wide and strongly blue-shifted absorption components. The lack of correlation between the mass-ejection process and the flickering activity suggests that the two phenomena have different physical origins. It will be worth repeating the search for such a correlation once MWC 560 will be again in a state of higher speed, discrete mass-ejection as it was in early 1990 (when ejection velocity approached ∼6000km/s).