COMMISSION 27 OF THE I. A. U.
        INFORMATION BULLETIN ON VARIABLE STARS
                     Number 1112

                                Konkoly Observatory
                                Budapest
                                1976 March 8



      OBSERVATIONS OF YZ CANIS MINORIS - NOVEMBER

              AND DECEMBER 1975


During November and December 1975, observations were carried out
at Boyden Observatory of the flare star YZ Canis Minoris (R.A. 7h42m
decl. 3d39' (1968.0), visual magnitude 11.6).
The 91 cm Nishimura reflector was used for this work, with a Johnson 
B. filter and a cooled EMI6256A photomultiplier tube as the
detector.
The total monitoring time was 33h46m12s. During this time nine
flares were recorded. Of particular interest is the flare event
which occurred on the 7th December. The ((I_0+f)-I_0))/(I_0) value was 
particularly large, viz. 16.30. This was preceded by a flare of 
((I_0+f)-(I_0))/(I_0)
value 2.72 a few minutes earlier. This activity was undoubtedly a
single event in that the slow decay continued for the rest of the
night.





                  A.H. JARRETT and J.B. GIBSON
                  Boyden Observatory, Department
                  of Astronomy, University of the
                  Orange Free State, Bloemfontein.
                  Republic of South Africa.


                               YZ CMi - NOVEMBER AND DECEMBER 1975
Date Total         Rise        Max.        Ends        Comments    ((I_0+f)-(I_0))/(I_0)     Air Mass
Hours                         (U.T.)                                                           Max.
27th 1h44m42s
Nov.

Monitoring Times   (U.T.)
22h13m06s- 22h33m30s
22 35 92 - 24 00 00
28th 3h13m00s    22h23m56s   22h23m57s   22h24m18s     Flare            0.46+-0.07             1.7438
                 22 43 11    22 43 15    22 45 42      Flare            0.98+-0.14             1.6017

Monitoring Times (U.T.)
00h00m00s- 00h20m29s
00 27 36 - 02 10 12
22 07 12 - 23 17 12
29th 1h50m48s    22 14 00    22 14 18    22 14 42     Slow flare        0.40+-0.11             1.7935

Monitoring Times (U.T.)
22h05m00s- 23h08m42s
23 12 54 - 24 00 00
30th 2h35m48s

Monitoring Times (U.T.)
00h00m00s- 00h20m54s
00 22 06 - 01 25 42
01 33 12 - 02 17 54
22 07 00 - 22 33 36
1st 1h09m36s
Dec.

Monitoring Times (U.T.)
22h48m54s- 22h52m30s
22 54 00 - 24 00 00
2nd 3h56m06s     00h36m15s   00h36m28s   00h37m48s    Probably a flare  0.63+-0.06            1.2067

Monitoring Times (U.T.)
00h00m00s - 01h01m18s
01 07 54  - 02 09 54
22 07 12  - 24 00 00

                                              Table (cont.)
        Total     Rise         Max.        Ends      Comments   ((I_0+f(-(I_0))/(I_0)        Air Mass
Date    Hours                  U.T.                                                            Max.
3rd 3h53m48s    00h20m51s    00h21m09s    00h22m00s  Flare              0.58+-0.11            1.2194
                01 53 18     01 53 47     01 57 00   Slow flare         0.53+-0.11            1.2073
                22 22 24     22 22 26     22 22 39   Possibly a flare   0.41+-0.09            1.6092

Monitoring Times (U.T.)
00h00m00s - 00h39m06s
00 42 18  - 01 02 48
01 06 54  - 02 08 00
22 06 54  - 24 00 00
4th 2h01m54s

Monitoring Times (U.T.)
00h00m00s - 00h01m48s
00 03 98  - 01 01 36
01 05 42  - 02 08 00
6th 1h24m30s   23 03 41      23 03 42      23 03 52  Probably a spike   0.67+-0.09           1.3564

Monitoring Times (U.T.)
22h35m30s - 24h00m00s
7th 4h06m48s  00 35 00      00 36 02          -     Flare               2.72+-0.14           1.1926
              00 36 52      00 38 05          -     Flare              16.30+-0.12           1.1916
One event     01 28 12      01 29 18      01 29 48  Slow flare          1.44+-0.11           1.1996
              01 30 54      01 31 18      01 31 48  Slow flare          1.11+-0.11           1.2012

Monitoring Times (U.T.)
00h00m00s - 01h14m36s
01 19 30  - 02 18 00
22 06 18  - 24 00 00
8th 4h00m24s 23 14 04      23 14 05      23 14 18   Possibly a small    0.40+-0.08           1.3023
                                                    flare

Monitoring Times (U.T.)
00h00m00s - 00h43m48s
00 48 06  - 02 10 00
22 05 18  - 24 00 00
9th 3h48m48s  02 00 48    02 00 50       02 00 54   Possibly a small flare0.41+-0.06         1.2503
              02 01 14    02 01 20       02 01 42   Possibly a flare      0.64+-0.11         1.2511


                          Table (cont.)

Date Total     Rise      Max.     Ends  Comments    ((I_0+f)-(I_0))/(I_0)  Air Mass
     Hours               U.T.                                                 Max.

Monitoring Times (U.T.)
00h00m00s - 00h35m12s
00 39 06  - 02 08 06
22 13 24  - 23 58 00