Peremennye Zvezdy (Variable Stars) 27, No. 6, 2007 Received 3 September; accepted 26 October.

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New GCVS Versions for Three Southern Constellations

N.N Samus^1,2, E.N. Pastukhova¹, O.V. Durlevich²

1. Institute of Astronomy, Russian Academy of Sciences, 48, Pyatnitskaya Str., Moscow 119017, Russia

2. Sternberg Astronomical Institute, 13, University Ave., Moscow 119992, Russia

1. INTRODUCTION

The first three volumes of the 4th edition of the General Catalogue of Variable Stars (GCVS), containing information on our Galaxy's variable stars in all the 88 constellations, were published about 20 years ago (Kholopov, 1985ab; Kholopov, 1987). They contained more than 28000 variable stars. Since then, about 12000 variable stars have been added to the GCVS system via Name Lists of Variable Stars, regularly published in the Information Bulletin on Variable Stars. The electronic GCVS version available at the GCVS site (http://www.sai.msu.su/gcvs/gcvs/) contains all these stars, those of the 4th edition and those of the Name Lists published since (Nos. 67-78), but the data presented for the Name-List stars is incomplete. (It should be reminded that the coordinates of variable stars in the web GCVS version have been considerably improved compared to the original paper version; cf. Samus et al., 2006, and references therein.) For many GCVS stars of the main edition, new publications appeared, demanding changes in the astrophysical information provided by the GCVS.

At the recent General Assembly of the International Astronomical Union (IAU), the IAU Commission 27 "Variable Stars" and the IAU Division V "Variable Stars" discussed the future of variable-star catalogues. The variable-star community is facing serious problems because of the current flow of new automatic discoveries, usually not accompanied with a sufficiently thorough analysis of new results. Commission 27, on behalf of Division V, created an informal working group to discuss these problems and suggest a solution. Meanwhile, it was generally agreed that attempts to prepare a new GCVS version providing up-to-date information were desirable.

It is also obvious that the variable-star classification system used in the 4th GCVS edition should be revised for the new GCVS versions. One of us (N.N.S.) presented a draft new classification scheme to the IAU Commission 27 (see
http://www.sai.msu.su/gcvs/future/classif.htm). It was understood that we would tentatively use this draft scheme in our GCVS work, while the variable-star community would send us suggestions of its improvement.

2. RESULTS

As the first approach to the new GCVS version, we have looked into information available for the GCVS and Name-List stars in three southern constellations, Antlia, Ara, and Telescopium. Earlier, we already approached this task for the constellation of Telescopium and gained some experience in using data available online for improving the GCVS information; we published our results mainly for stars with no light elements in the 4th GCVS edition (Pastukhova et al., 2004). We also used data mining to derive light elements for 100 stars, most of them objects of the NSV catalogue (Kazarovets et al., 2005).

For the constellations of Antlia, Ara, and Telescopium, the most important source of online photometric information is the ASAS-3 survey (Pojmanski, 2002). Many stars in these constellations are contained in the ASAS-3 variable-star catalogue. We are not always satisfied with light curve solutions and period determinations of the ASAS-3 catalogue and sometimes attempted to improve these data. Moreover, for variable stars not in the ASAS-3 catalogue, it is often possible to derive data needed for the GCVS using ASAS-3 raw data. Unfortunately, during 2006, the ASAS-3 data were not completely accessible due to hardware problems in Poland. Additional information for some stars in Antlia could be found in the ROTSE1/NSVS data (Wozniak et al., 2004).

We prepared a complete new GCVS version for 1317 stars in the three constellations, "old" GCVS (4th edition) stars as well as stars named in the Name Lists Nos. 67-78 (the number 1317 does not include non-existing stars; stars having several GCVS names are counted once, in accordance with their main designations). For purposes of evaluation of the new classification system, a subversion using the new draft classification is available at the GCVS Internet site (http://www.sai.msu.su/gcvs/future/). In this subversion, two types are given for each star, according to the old and new classification system. Another subversion, with GCVS information revised but based on the GCVS (4th edition) classification scheme, has been introduced in the main online GCVS version, including data provided by the GCVS search engine.

The Table below contains those stars of the new-classification subversion where information (types, light elements) was significantly revised by us, primarily by means of data mining. The columns are traditional for the GCVS (with the exception that, for eclipsing binaries, the brightness in the secondary minimum is given in the Table rather than in Remarks). Asterisks after GCVS names refer to the short, most important Remarks given after the Table. More detailed remarks, with additional references, can be found at the GCVS site. Like in our earlier catalogues, an asterisk in the " or " column means "".