COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                     Number 1588

                                 Konkoly Observatory
                                 Budapest
                                 1979 April 24




    FLARE OBSERVATIONS OF UV CETI DURING NOVEMBER 1975


  The flare star UV Ceti (R.A.=01h36m24s, declination=-18d13'
(1950), visual magnitude 12.9 at minimum, spectral type dM5.5e)
was monitored from Boyden Observatory during November 1975.
  Of the 17 flares recorded, three were very intense; the 
outbursts peaking at 18h15m32s and 02h07m05s on the night of 2-3
November were confirmed visually through the 15 cm finder.
Throughout this work the 41 cm Nishimura reflector was used with
an uncooled EMI 6256A photomultiplier tube and a Johnson B 
filter.
  Possibly of particular interest are the six spike events noted 
during the period. Generally they were of 3 to 6 seconds 
duration with (I_0+f-I_0)/I_0 values between 1.10 and 2.05. They are
significantly shorter in lifespan than UV Ceti flares we have
previously recorded.
  We are particularly indebted to Prof. F.D.I. Hodgson, Director 
of the Institute of Groundwater Studies at the University,
for making his department's Hewlett Packard Model 9825 microcomputer 
and digitizer available for the reduction of our photometric 
data.



                   A.H. JARRETT and J. VAN ROOYEN
                   Boyden Observatory
                   Astronomy Department
                   University of The Orange Free State
                   Bloemfontein 
                   Republic of South Africa



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              MONITORING TIME         FLARE MAXIMUM  I_0+f - I_0)/I_0                               sigma(mag)            m_lim - m_0
                    U.T.                   U.T.                        2.5 log((I_0+f - I_0)/I_0)   = -2.5log|sigma|/I_0  =sigma(mag)-1.19
1975                                                   
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02/43 Nov     18h00m02s- 21h32m18s   + 18h15m32s        7.40                      2.17                     2.19                 1.01
              21 38 24 - 22 04 24    * 23 27 00         1.11                      0.17.                    2.20                 1.06
              00 09 29 - 01 12 30
              01 13 54 - 02 22 02    + 02 07 05       >18.59                     >3.17                     2.15                 0.96
03/04 Nov     17 48 15 - 19 28 07      17 58 15         3.21                      1.27                     1.89                 0.70
              19 29 09 - 20 59 07    * 18 45 28         2.05                      0.78                     1.89                 0.70
              21 04 54 - 20 27 00
              20 32 09 - 02 20 11      18 47 40         2.02                      0.76                     1.89                 0.70
                                       22 53 49         1.18                      0.18                     1.97                 0.78
                                     * 01 53 24         1.39                      0.35                     1.97                 0.78
04/05 Nov     18 03 00 - 23 07 42      22 21 01         1.74                      0.60                     2.03                 0.84
              23 12 02 - 02 06 14    * 22 23 46         1.10                      0.11                     2.03                 0.84
                                       01 03 18         1.62                      0.52                     1.89                 0.70
                                       01 09 12         1.25                      0.24                     1.89                 0.70
05/06 Nov     22 15 06 - 02 01 02      23 32 48         1.15                      0.15                     1.86                 0.67
                                     * 23 51 41         2.01                      0.76                     1.86                 0.67
                                     * 01 05 17         1.42                      0.38                     1.86                 0.67
14/15 Nov     17 48 06 - 01 50 06      19 20 51         2.51                      1.00                     1.31                 0.12
29/30 Nov     18 05 21 - 18 45 00      19 27 38         2.07                      0.79                     2.28                 1.09
              18 49 12 - 19 16 54                           
              19 22 24 - 22 00 19
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                      * SPIKE EVENT
                      + CONFIRMED VISUALLY

                       [FIGURE 1]
                       [FIGURE 2]