COMMISSION 27 OF THE I. A. U.
         INFORMATION BULLETIN ON VARIABLE STARS
                     Number 1664

                                    Konkoly Observatory
                                    Budapest
                                    1979 August 27



          LOW INTENSITY FLARES OF V645 Cen



     V645 Cen (R.A. 14h26m42s, declination -62d29'(1950), 11.3
visual magnitude at minimum, spectral type dM5e) was observed from
Boyden observatory on the nights of 22/23 and 25/26 April 1976.
     We used the 41 cm Nishimura reflector, fitted with a photometer 
consisting of an uncooled EMI 6256A photomultiplier tube
and a standard Johnson B filter.
     Observing conditions were very good through the monitoring 
periods.
     Of the seventeen low intensity flares recorded only the
spike flare shown in the diagram was significantly above the noise
level of the recording gear. The others we regard as probable
flares; although they were of low intensity we nevertheless, in
the light of previous experience, consider that they should be
reported. They are similar in character to some of the V645 Cen
flares we have previously recorded.                 
                    
                 Monitoring Time of flare
----------------------------------------------------------------
Date     time(U.T.)  maximum (U.T.) (I_0+f - I_0)/I_0
----------------------------------------------------------------
1976                                           Comments
22 April   20h35m00s   21h52m57s      0.50  Probable small flare
        to 23 20 00    21 55 26       0.60     "   "   "
                       21 59 41       0.57     "   "   "
                       22 17 30       0.42     "   "   "
                       22 45 29       0.48     "   "   "
1976                   22 59 00       0.63     "   "   "
25 April   17 40 00    19 04 52       0.59  Probable small flare
        to 23 00 00    19 05 00       0.52     "   "   "
           23 06 00    19 26 20       0.56     "   "   "
        to 24 00 00    21 28 03       0.44     "   "   "
                       21 47 57       0.45     "   "   "
1976
26 April   00 00 00    02 01 38       0.53  Probable small flare
        to 03 36 00    02 03 37       0.56     "   "   "
                       02 07 56       0.53     "   "   "
                       02 09 04       0.58     "   "   "
                       02 11 22       0.48     "   "   "
                       02 46 42       0.76  Spike flare
----------------------------------------------------------


                            [FIGURE 1]


    The reductions were made with a Hewlett Packard Model 9 825
microcomputer and digitizer, kindly made available by Professor
F.D.I. Hodgson, the Director of the Institute of Groundwater Studies
at the university.





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




Reference:
Jarrett, A.H. and van Rooyen, J. 1979, I.B.V.S., No. 1641