COMMISSIONS 27 AND 42 OF THE IAU
           INFORMATION BULLETIN ON VARIABLE STARS
                        Number 4097

                                             Konkoly Observatory
                                             Budapest
                                             3 October 1994                      
                                             HU ISSN 0374 - 0676





           Photoelectric minima of eclipsing binaries




The following Table gives the photoelecric minima obtained in the years 1991-1993
at the N Copernicus Observatory and Planetarium in Brno (Czech Republic) by means
of the Nasmyth type 0.4-m telescope.

The telescope was used with a single channel photometer and EMI6256B 
photomultiplier. Measurements were made in the UBV-system. The integration time 
of one measurement was ten second.

The times of minimum brightness and their standard deviation were determined by 
Kwee-van Woerden's (1956) method. The name of star, the name of the filter, 
heliocentric time of minima, standard deviation, different values of O-C
and abbreviations of the observers's name are given in Table 1. The 
abbreviations in the column ``Observer'' means:

DH: Dalibor Hanzl
EN: Eva Neureiterova
PH: Petr Hajek
TH: Tomas Hudecek
MN: Martin Navratil
MZ: Miloslav Zejda

Data for calculating the O-C residuals have been taken from the 
following literature:

OC(I): SAC65, Krakow, 1993

OC(I): GCVS, Moscow, 1985-1987

Table 1


Name          JDhel        err.    OC(I)     OC(II)  Obs.


RT And  V  s  48506.3373  0.0016 -0.0035    -0.0017  MN
        V     48600.3639  0.0005 -0.0019    -0.0001  MN
        B     48600.3629  0.0003 -0.0029    -0.0011  MN
        U     48600.3655  0.0004 -0.0003    -0.0015  MN
        V     48646.2751  0.0014 -0.0025    -0.0007  MN
        B     48646.2746  0.0008 -0.0030    -0.0012  MN
        U     48646.2754  0.0004 -0.0022    -0.0004  MN
DS And  V     48537.4321  0.0005 +0.0050  = +0.0050  DH
        B     48537.4293  0.0007 +0.0023  = +0.0023  DH
RX Ari  V     48262.3965  0.0002 -0.0073    +0.0097  DH
        B     48262.3951  0.0005 -0.0087    +0.0083  DH
TT Aur  V     48599.3018  0.0004 +0.0073    -0.0059  DH
        B     48599.3007  0.0002 +0.0062    -0.0070  DH
        U     48599.3016  0.0003 +0.0071    -0.0061  DH
BF Aur  V  s  48271.3680  0.0004 +0.0052  = +0.0052  DH/PH
        B  s  48271.3694  0.0003 +0.0066  = +0.0066  DH/PH
        U  s  48271.3724  0.0011 +0.0096  = +0.0096  DH/PH
VW Cep  V     48276.4159  0.0005 -0.0000    -0.0533  EN
        B     48276.4144  0.0005 -0.0015    -0.0548  EN
GS Cep  V  s  48461.4968  0.0012 +0.0006             DH
        B  s  48461.4969  0.0020 +0.0007             DH
        V     48500.4957  0.0008 +0.0015             DH
        B     48500.4949  0.0008 +0.0007             DH
        V     48503.4394  0.0011 +0.0019             DH
        B     48503.4397  0.0006 +0.0022             DH


Table 1 (cont.)


Name           JDhel        err.   OC(I)     OC(II)   Obs.


GS Cep  V  s  48567.4472  0.0013  -0.0060               DH
        B  s  48567.4484  0.0013  -0.0048               DH
V680 Cyg V    48445.4665  0.0023  +0.0139     +0.0433   DH/TH
        B     48445.4622  0.0008  +0.0096     +0.0390   DH/TH
TT Her  V     48444.4762  0.0011  -0.0038     +0.0138   DH/TH
        B     48444.4816  0.0008  -0.0016     +0.0192   DH/TH
        V     48839.4120  0.0011  +0.0021     +0.0209   DH
        B     48839.4124  0.0003  +0.0025     +0.0213   DH
V566 Oph V    48443.4616  0.0006  +0.0014     +0.0164   DH/TH
        B     48443.4623  0.0007  +0.0021     +0.0170   DH/TH
V839 Oph V    48500.3775  0.0009  +0.0018     +0.0741   DH
        B     48500.3772  0.0006  +0.0015     +0.0738   DH
        V     48805.4965  0.0002  +0.0048     +0.0826   DH
        B     48805.4980  0.0002  +0.0063     +0.0841   DH
FT Ori  V     48273.2980  0.0003  +0.0021  =  +0.0021   DH/EN
        B     48273.2975  0.0007  +0.0016  =  +0.0016   DH/EN
        U     48273.3009  0.0004  +0.0050  =  +0.0050   DH/EN
V392 Ori V    48272.3628  0.0016  +0.0070  =  +0.0070   DH
        B     48272.3601  0.0008  +0.0043  =  +0.0043   DH
GP Peg  B     48476.4195  0.0007  +0.0008     -0.0177   MZ/DH
IU Per  V     48567.3246  0.0011  -0.0176     +0.0090   DH
        B     48567.3224  0.0011  -0.0198     +0.0068   DH
        U     48567.3239  0.0028  -0.0183     +0.0083   DH
GR Tau  V     48619.2975  0.0010  +0.0008     -0.0112   DH
        B     49619.2971  0.0011  +0.0004     -0.0016   DH
BU Vul  V     48479.4249  0.0009  +0.0038     +0.0028   DH
        B     48479.4253  0.0005  +0.0042     +0.0032   DH



Moments of the secondary minima are labelled by ``s''. As far as the data for
calculating the time of the secondary minima are not given in the above
mentioned literature, we use the phase 0.5 for calculating the O-C of the
secondary minima (the secondary minimum is supposed to be in mid-phase between 
the primary ones).

In case the elements in both sources are equal, the O-C's are also equal (this
is indicated by the sign ``=''). The GCSV period of GS Cep is definitely wrong,
so corresponding (O-C) values are not given.






Dalibor HANZL
N. Copernicus Observatory
and Planetarium
Kravi hora
616 00 Brno
Czech Republic
e-mail: HANZL@vm.ics.muni.cz



References:

GCVS, Moscow, 1985-87

Kwee, K. K. and van Woerden, H., 1956,  Bull. Astron. Inst. Neth., 
12, No.464 [BIBCODE 1956BAN....12..327K ]

SAC 65, Krakow, 1993