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Astron. Astrophys. 350, 491-496 (1999)

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1. Introduction

This paper follows in a series of reports (see Richichi et al. 1994, 1996 and 1997, hereafter Papers I, II and III), on discoveries of new binary stars, or on re-observations of known systems. The data were collected in the course of two long-term routine programs of lunar occultations (LO) in the near-IR, which have been active for a number of years at the TIRGO and Calar Alto observatories. We refer the reader to Paper II for a detailed description of our observational and data reduction methods, and of the instruments and telescopes used.

The observations log is reported in Table 1, following the same format of Paper III. In summary, Columns (1) through (3) list the source identification, the date of the event and the telescope used. In this latter column, the symbols identify the telescopes: T for the 1.5 m TIRGO telescope, and C1, C2 for the Calar Alto 1.23 m and 2.2 m telescopes respectively. In all cases InSb photometers equipped with broad band K filters were used. The characteristics of the acquisition systems and filters are described in Paper II. Column (4) lists the aperture of the diaphragm, while Columns (5) and (6) list the sampling time of the lightcurves, and the integration time for each data point where applicable. Columns (7) and (8) list the total magnitude of the star in the V and K filters. The V magnitudes are taken from the literature, while the K magnitudes are from our own photometric data except in the case of three sources, for which we present an estimate based on the expected V-K color for the given spectral type. In Columns (9) and (10) we report the spectral types and distances, again extracted when available from the literature; in the case of multiple determinations, the most frequent or most recent were used. The distances are based on Hipparcos parallaxes. Finally, the last column reports a short comment on whether the binary was previously known or not. Table 2 lists the cross-identifications of the observed sources. In two cases, no cross-identification with other catalogues could be established, and we provide coordinates from the HST Guide Star Catalogue.


[TABLE]

Table 1. List of the occultation events and the circumstances of their observation.
Notes:
a) value estimated from the V magnitude and the expected color for the given spectral type



[TABLE]

Table 2. Cross identifications


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© European Southern Observatory (ESO) 1999

Online publication: October 4, 1999
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