COMMISSION 27 OF THE I.A.U.
                 INFORMATION BULLETIN ON VARIABLE STARS
                              Number 2956

                                                         Konkoly Observatory
                                                         Budapest
                                                         13 November 1986

                                                         HU ISSN 0374 - 0676


                   NEW PHOTOELECTRIC OBSERVATION OF W UMa
                           SYSTEM 44i BOOTIS

The eclipsing variable 44i Boo is the fainter component of the visual
binary ADS 9494. It is the brightest known W UMa-type eclipsing binary star
(Bopp and Witzigmann, 1982).
   It has been observed many times since its discovery (Schilt, 1926),
(Eggen, 1948; Binnendijk, 1955; Schmidt and Schrick, 1957; Wehlau and
Leung, 1961; Semeniuk, 1963; Catalano and Saitta, 1964; Brown and Pinnington,
1969; Kurpinska and Van't Veer, 1970; Gieseking, 1977; Hopp et al., 1977;
Breinhorst, 1978; Duerbeck et al., 1978; Mikolajewska and Mikolajewski,
1980; Rovithis and Livaniou, 1981; Hopp and Witzigmann, 1982).
   The system 44i Boo is known to have abrupt period changes as well as
strong light activities. According to Bergeat et al. (1972) the star has an
"active" period of 3 years followed by a 7 years "quiet" period. The former
active periods were 1945-1947, 1955-1957, 1966-1968, 1976-1978. Thus new
active period is expected to be in 1986-1988.
   As a part of a program to study this eclipsing binary, photoelectric
observation has been done with the 40 cm Cassegrain telescope of ALBATTANI
Observatory (IRAQ-TARMIYA, latitude = 33d37'32" N, longitude = 44d28'.6 E)
during the nights 26, 27, 28 of July 1986.
   An unrefrigerated photometer equipped with a 1P21 photomultiplier tube
and UBV filters in close accordance with standard Johnson's filter was
attached to the telescope (Kadourie et al. 1986).
   The observations were made in B and V filters only.
   The comparison star was 38 Boo. A total of 50 normal points have been
obtained from 213 observation points in each filter and the light curves
are shown in Figures 1 and 2 respectively. The probable error for a single
observation was +-0.025 in V and +-0.03 in B filter.


                           [FIGURE 1]

     Figure 1  Light curve of 44i Boo in blue filter

                           [FIGURE 2]

     Figure 2  Light curve of 44i Boo in yellow filter


   The phases are computed according to Duerbeck's (1978) ephemeris:

   MIN I (Hel.) = 2439852.4903 + 0.2678159d*E

   The following table shows the times of minima and O-C values.

Filter   Min.    J.D. (Hel.)      O-C

  B       I     2446640.30262    0.0174
  B       II    2446638.29375    0.0171
  V       I     2446640.30052    0.0153
  V       II    2446638.29390    0.0151


                      HAMID M. AL-NAIMIY, HASAN A. FLEYEH
                     ASSEM O. AL-SIKAB, JINAN M. AL-RAZZAZ
                      Space and Astronomy Research Centre
                        Council for Scientific Research
                          Jadiriyah, Baghdad, Iraq



References:

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   Astrophys. 17.215 [BIBCODE 1972A&A....17..215B ]
Binnendijk, L., 1955, Astron. J. 60.355 [BIBCODE 1955AJ.....60..355B ]
Breinhorst, R.A., 1978, Acta Astron. 28.579 [BIBCODE 1978AcA....28..579B ]
Brown, B.M.K. and Pinnington, E.H., 1969, Astron. J. 74.538 [BIBCODE 1969AJ.....74..538B ]
Catalano, S. and Saitta, T., 1964, Mem. Soc. Astron. J. 35.43 [BIBCODE 1964MmSAI..35...43C ]
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