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\IBVShead{4189}{5 May 1995}                      % Use it with dummy or empty arguments

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\title{X PERSEI}

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The Be/X-ray binary X Persei is the optical counterpart of X-ray pulsar 4U
0352+30. Possible orbital period of the system is the 580 day periodicity
detected in the radial velocities of the Balmer lines (Hutchings, 1977),
in spite of existence of some doubts (Penrod \& Vogt, 1985). The star is
a known optical variable on time scales from minutes to years. The most
comprehensive optical light curve over the past decades is presented by
Roche et al. (1993).

X Per has been observed with 60 cm telescope and photon counting photometer
of the National Astronomical Observatory Rozhen. HR\,1197 (V=6.25, B$-$V=0.20,
U$-$B=0.14) served as the comparison star. The APR software (Kirov et al.,
1993) was used during the data reduction.

Our data are summarized in Table 1. Figure 1 presents the V band light curve
over the period 1986-1995. Our observations showed the optical low state that
began in the mid-1990 finished in the spring of 1993. Since this time the star
has been in optical high state. A clear similarity between the light maximum in
1987-1988 and that in 1993-1994 is visible. The displacement is about 2400
days, i.e. 4 times larger than the supposed orbital period.

The last observations indicate that the optical high state is almost over
and X Per is going to a new low state now. May be the star will lose its 
circumstellar  disk again as it was observed in 1990 (Norton et al., 1991;
Roche et al., 1993).
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Figure 1. V band light curve of X Per. Circles indicate our data. The
light curve before JD\,2448500 is taken from Roche et al. (1993).
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\centerline{Table 1}
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\begin{tabular}{ccccccccc}
\hline
JD\,2440000+&V&B$-$V&U$-$B& &JD\,2440000+&V&B$-$V&U$-$B\\
\hline
\\
8545.57&6.81&0.09&$-$0.68& &9341.27&6.47&0.18&$-$0.78\\
8620.52&6.76&0.08&$-$0.64& &9343.42&6.47&0.19&$-$0.78\\
8712.29&6.78&0.11&$-$0.73& &9357.43&6.44&0.20&$-$0.78\\
8734.26&6.76&0.05&$-$0.68& &9366.46&6.44&0.19&$-$0.78\\
8841.52&6.75&0.13&$-$0.66& &9572.51&6.34&0.26&$-$0.73\\
8842.56&6.76&0.11&$-$0.67& &9573.52&6.33&0.26&$-$0.73\\
8905.56&6.78&0.09&$-$0.70& &9597.50&6.26&0.26&$-$0.73\\
8916.42&6.78&0.09&$-$0.70& &9598.48&6.27&0.24&$-$0.73\\
9028.22&6.78&0.05&$-$0.66& &9715.32&6.38&0.21&$-$0.75\\
9046.26&6.76&0.06&$-$0.66& &9748.23&6.45&0.21&$-$0.81\\
9195.55&6.45&0.21&$-$0.75& &9772.23&6.48&0.21&$-$0.83\\
9197.54&6.42&0.21&$-$0.76& & & & & \\
9340.28&6.47&0.18&$-$0.79& & & & & \\
\hline
\end{tabular}
\end{center}
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We gratefully acknowledge Dr. N. A. Tomov for help in observations. This
work was partly supported by NSF (F-466/94).

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% Call for macros \authors - \authorsrightcol - \endauthors
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R. K. ZAMANOV
NAO Rozhen, POB 136,
4700 Smoljan, Bulgaria
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V. I. ZAMANOVA
Planetarium, POB 132,
4700 Smoljan, Bulgaria
\endauthors

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\references

Hutchings, J. B., 1977, {\it MNRAS}, {\bf 181}, 619

Kirov, N., Antov, A., Genkov, V., 1993, {\it Compt. Rend. Acad. Bulg. Sci.},
{\bf 44}, No.\,11, 5

Northon, A. J., Coe, M. J., Estela, A. et al., 1991, {\it MNRAS}, {\bf 253},
579

Penrod, G., Vogt, S., 1985, {\it ApJ}, {\bf 299}, 653

Roche, P., Coe, M. J., Fabregat, J., McHardy, I. M., Norton, A. J., Percy, J. R.,
Reglero, V., Reynolds, A., Unger, S. J., 1993, {\it A}\&{\it A}, {\bf 270}, 122

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