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Up: A photometric study

1. Introduction

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Figure 1: Location of the tex2html_wrap_inline1372 area covered by fields A, B, C and D. Coordinates of star 45 Oph can be found in the text

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Figure 2: Chart of Field C, south-west the star 45 Oph

A systematic photographic survey initiated in 1959 by A. Terzan (A. T.) in the direction of the Bright Cloud B in Sagittarius has been going on since 1976 at the ESO 1 m Schmidt telescope (Chile). A large number of peculiar objects have already been recognized, e.g. variable stars, galactic open clusters, galactic globular clusters, diffuse objects, planetary nebulae and proper motion stars (Terzan 1990 and references therein; Terzan & Gosset 1991; Acker et al. 1992; Cuisinier et al. 1993, 1994).

The tex2html_wrap_inline1374 programme field is centred on the star 45 Oph (tex2html_wrap_inline1376; tex2html_wrap_inline1378, equinox 2000.0).

We present now the results of the search for long period variable stars in the last part of the programme field. The investigated region is a tex2html_wrap_inline1380 area, situated south-west the star 45 Oph, and defined by: tex2html_wrap_inline1382 and tex2html_wrap_inline1384. It corresponds to part C of the programme field (see Fig. 1 (click here), Table 1 (click here), and Fig. 2 (click here)). A catalogue of positions and photographic R magnitudes at observed maximum and minimum brightness is given for 1061 newly detected variables. The limiting magnitude of the detection is about 18. If we take into account the 3369 similar objects previoulsy discovered by Terzan et al. (1982, 1988, 1991), the total number of new variable stars discovered in our 100 square degree field amounts to 4430. The global catalogue will be available in electronic form at CDS via anonymous ftp cdsarc.u-strasbg.fr or 130.79.128.5



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