COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                     Number 632

                                      Konkoly Observatory
                                      Budapest
                                      1972 February 25


            PHOTOELECTRIC OBSERVATIONS OF YZ CMi


The flare star YZ CMi was monitored photoelectrically in the period of
co-operative observations 9-23 January, 1972. The observations were carried
out in the B-band with the 64-cm meniscus telescope. The observational results
are given in Table 1, 2 and figures.


P.F. CHUGAINOV
N.I. SHAKHOVSKAYA
Crimean Astrophysical Observatory

Table 1

Date,           Coverage (U.T.)
1972

Jan.9     18 00-18 28, 19 00-19 08, 20 39-20 45, 20 47-20 48
   14     18 04-19 03, 19 04-19 44, 19 48-21 41, 21 45-22 33,
          22 37-23 38, 23 39-24 00
   15     00 00-01 10, 01 12-01 30
   16     17 12-18 16, 18 22-18 38
   17     17 15-17 38, 17 39-18 12, 18 13-19 33, 19 38-19 47,
          19 50-20 58, 21 02-21 33, 21 34-22 41, 22 43-24 00
   18     00 00-00 33, 00 37-01 41, 01 43-01 50, 17 05-17 15,
          17 18-17 54, 17 56-19 45
   22     17 17-18 12, 18 13-19 58, 20 00-21 53, 21 55-22 22,
          22 26-23 16, 23 21-23 43, 23 48-24 00
   23     00 00-00 14, 00 19-01 04, 01 10-01 31, 17 26-19 54,
          19 59-21 51, 21 55-23 30, 23 37-24 00
   24     00 00-00 02, 00 09-00 35, 00 37-01 30

Table 2

Date     U.T.      t_h     t_a   (I_f-I_0)/I_0   sigma/I_0    P_B     Notes
1972   maximum       minutes      maximum		    minutes

Jan.14	18 54.8   0.8      4.0     0.58           0.048      0.85
        21 29.4   2.0     11.6     0.46           0.034      1.60
        23 32.6   0.6      8.4     0.21           0.030      0.76
        23 43.0   1.0     24.0     0.66           0.030      2.60
    15  00 55.8   5.2   > 35       1.15           0.034     14.2
    17  17 34.6   0.1      0.2     0.32           0.059      0.05     (1)
        18 03.2   1.0     16.0     2.36           0.049      5.61     (2)
        20 14.6   0.3     17.0     2.22           0.029      5.35     (3)
        21 28.2   0.8      4.0     0.36           0.024      0.69
        22 16.0   0.3     15       0.27           0.018      1.27     (4)
        23 00.5   0.5      5.3     0.23           0.037      0.42
    22  18 59.4   1.0      4.2     0.69           0.035      1.14
        20 03.5   0.9     10.3     0.42           0.021      2.28
        21 25.7   2.0     55.3     5.64           0.027     29.5
        23 00.0   0.4     24.8     8.17           0.030     10.8
    23  21 03.8   0.2      1.4     0.55           0.037      0.20
    24  00 21.5   0.2      1.5     0.59           0.030      0.17

1   Isolated peak; light curve is not presented.
2   Secondary maximum at 18 01.8.
3   Secondary maximum at 20 20.3.
4   Secondary maximum at 22 14.

Errata

Please add to the Tables "Coverage" published in IBVS No. 615 and 616
respectively, the following (read in the Coverage-Table of No. 616 Sept.
instead of Oct.):

Coverage

Sept.16    (17 17-19 14, 19 18-20 57, 21 06-21 12, 21 17-22 04,
            22 07-22 19, 22 24-23 01, 23 05-23 34, 23 37-24 00)
     17    (00 00-00 03, 00 09-00 32, 00 40-01 06, 01 25-01 46)
Oct. 15     19 01-19 08, 19 09-19 36, 19 42-20 40, 20 42-21 41,
            21 42-21 58, 22 00-22 09, 22 11-22 40, 22 42-23 21,
            23 26-23 44, 23 46-24 00
     16     00 00-00 02, 00 03-00 23, 00 24-00 30


                         [FIGURE 1]
                         [FIGURE 2]