3. The light curves
Fig. 2 clearly shows the gradual increase in visual magnitude V by about 0:m07 y-1 with associated reddening in , and (the latter amounting to about 0:m05 y-1) and cyclic microvariations. The brightening phase is strongly present in y, and decreases towards b and v. Superimposed on these longer-term trends are the microvariations (the so-called Cygni-type variations near the minimum of the SD cycle, see van Genderen et al. 1997a,b, and the longer [ 100 d] cycles near maximum) and a much slower oscillation about the gradual, brightening trend. The data collected in 1996 show an apparently steep descent in y accompanied by a blueward shift in the colour index. Note that this apparent steep descent could have been enhanced by a coincident descending part of the superimposed variability.
© European Southern Observatory (ESO) 1998
Online publication: April 20, 1998