COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                     Number 1353

                                    Konkoly Observatory
                                    Budapest
                                    1977 October 21




        PHOTOELECTRIC OBSERVATIONS OF 44i BOOTIS
    Veroffentlichung der Wilhelm Foerster Sternwarte Nr. 48




     This bright W UMa type variable was investigated for sudden 
period changes and disturbances in the light curve by Bergeat
et al. (1972) and Duerbeck (1977). From their investigations a
period jump and lightcurve activity could be expected in 1977.
     A total of 375 V observations were carried out in six
nights. An unrefrigerated RCA 1P21 multiplier, attached at the
75 cm reflector (2 nights) or at the 31.4 cm refractor (4 nights)
of the Wilhelm Foerster Observatory was used. The comparison star
was 47 k Boo in all nights. A correction for extinction was made
in the usual way.
     From this material, the minima of Table 1 were determined
by Pogson's method:

Table 1: Minimum times

Epoch   Minimum        O-C    Instrument
12621 2443232.5917   -0.0031d   75 cm
         +- 0.0005
12695     252.4113   -0.0019    31.4 cm
          +-0.0010
12826     287.4937   -0.0033    31.4 cm
          +-0.0005

The ephemeris is adopted from Duerbeck (1975).
Unfortunately only the primary minima of the star were
observed. But in all cases there are evidences for activities in
the curves,  observed as small minima in the descending branches.
Table 2 gives the dates, phases, amplitudes and durations:

Table 2: Lightcurve activities

Date     Phase     Amplitude  Duration
2443232d 0.865P      0.02m     0.008d
    252  0.873       0.02:     0.010
    287  0.771       0.03      0.010
    295  0.731       0.03      0.03

                    [FIGURE 1]

  Fig. 1. Phase drift of the light-curve disturbances.
  Circles - Duerbeck (1977), dots - this paper.

                    [FIGURE 2]

  Fig.  2. Mean light-curve of all observations of this paper.
  Diameter of dots represents the number of observations.


      The "shoulders" - as named by Duerbeck (1977) - are
constant in phase in Duerbeck's observations from 1975 up to
J.D. 2443252d in this paper at 0.870P. Then a drift started as
shown in Fig. 1. Also the amplitude increased. This is the reason
why the disturbances in the mean lightcurve of Fig. 2 reach from
the phase 0.75p to 0.89p. At least one can notice that the maxima
are of unequal height, the primary maximum is 0.01m less than
the secondary. Around the phase 0.06p a larger scatter as usual
was observed on J.D. 2443252d and J.D. 2443287d.
      We have to thank the Fritz Haber Institut for the 
possibility to use their DEC 10 calculator and Dr. H. Duerbeck for
supporting this work.





                                 U. HOPP
                                 S. WITZIGMANN
                                 M. KIEHL

                                 Wilhelm Foerster Observatory
                                 Berlin




References:
Bergeat, J., Lunel, M. end Sibille, F., Astron.Astrophys. 17, 215,
       1972 [BIBCODE 1972A&A....17..215B ]
Duerbeck, H., I.B.V.S. No. 1023, 1975
Duerbeck, H., private communication, in press, 1977