Baltic Astronomy, vol. 9, 165-170, 2000. PRELIMINARY 8 SCUTI STAR CATALOG R. Zechner Institute for Astronomy, University of Vienna, Tiirkenschanzstr. 17, 1180 Vienna Received December 3, 1999 Abstract. The new, now in late stage of development, catalog will be a compilation of 400 <5 Scuti stars. Identification, positions, UBV- and ubvyp photometric as well as spectral type and stellar astrophysical parameters will be given. This database includes references which were published until December 1999. Key words: stars: variables: 5 Set, SX Phe types 1. INTRODUCTION S Scuti stars are pulsating variables of spectral class Al to F5 with luminosity classes V to III. They are situated in the cepheid instability strip on and slightly above the main sequence. They pul- sate with a large number of detectable low-order radial and nonradial p-modes, while there also exists evidence for the presence of g-modes. Luminosity variations of such stars range from less than a mil- limag to light amplitudes of about 0.3 mag or higher. Pulsation periods are characteristically in the order of 30 minutes to 8 hours. In many stars the shapes of the light curves vary markedly from cycle to cycle. The 5 Scuti stars have masses near 2 M© and they are in the main-sequence stage of evolution. They have characteristically nor- mal metal abundance and low space motion. Most of the stars that exhibit variations with these character- istics are Population I stars in a main sequence or early post-main sequence phase of evolution. However, there is also a group of stars that show similar variations but that have high space velocities and low metal abundances. These stars are not members of Population 166 R. Zechner 1, but they may be main sequence Population II stars. Both types of stars are referred to as 5 Scuti stars. (Breger 1979) 2. THE STRUCTURE OF THE CATALOG This catalog is a compilation of approximately 400 variable stars. The main goal of this work is to present an extensive and up to date list of 8 Scuti stars. The catalog intends to be a comprehensive re- view of observational characteristics of all the S Scuti stars known until now. This implies stars contained in earlier catalogs together with other new discovered variables. So more information compared to previous catalogs is given. This database is a collection of in- formation related to identification, positions, photometry, spectra, pulsation features and literature references and its size is 25 MB. The catalog contains a current data table, references, notes, queries and publications. Besides, an important point is that all the data will be evaluated and interpreted. The catalog will be finished soon and published in the Sixth Vienna Workshop in Astrophysics: Delta Scuti and related stars (Zechner 2000). The main source of information is the Rodriguez Catalogue (Ro- driguez et al. 1994), which is based on the 4th Edition of the General Catalogue of Variable Stars (GCVS) Vol. I, II, III, IV (Kholopov et al. 1985a, 1985b, 1987a, 1990) and the Name Lists (NL) Nos. 67, 68, 69 (Kholopov et al. 1985c, 1987b, 1989), 70 (Kazarovets & Samus 1990) and 71 (Kazarovets et al. 1993). Spectral types (ST) and UBV indices are taken from several sources, most from Nicolet (1978). The sources of information for Stromgren indices, rotational velocities (v sin i) and radial velocities (RV) have been the catalogs of Hauck & Mermilliod (1990), Uesugi & Fukuda (1982) and Abt k Biggs (1972). The efficiency of the 5 Scuti star Catalog are to seek for stars and search for a specific value by using the find or the filter function. Also, it is possible to look up queries and to make own ones. More- over, references to the literature are given to search for publications about a specific 8 Scuti star. Furthermore, the catalog includes index cards to print a selected star in a default report layout. A graphical user interface helps to work with the catalog. Another advantage of the catalog is to make statistical plots in one place. In future new 5 Scuti type stars from the Hipparcos database will be included in the catalog. The Hipparcos Catalogue is the primary product of the European Space Agency's astrometric mission called Preliminary ó Scuti star catalog 167 Hipparcos. The satellite, which operated for four years, returned high quality scientific data from November 1989 to March 1993. So the catalog contains a large quantity of very high quality astrometric and photometric data. The Hipparcos Input Catalogue (Version 2) consists of more than 118 000 stars that need a careful examination. We also expect to put the catalog on the Internet and to make the tables available for the public. The database includes the following parameters: Table 1. Star ID Number of identification HD Designation from Henry Draper Catalogue HR Designation from Harvard Revised Catalogue (Bright Star Catalogue) SAO Smithsonian Astrophysical Observatory Star Catalogue BD Bonner Durchmusterung CD Cordoba Durchmusterung CPD Cape Photographic Durchmusterung CGVS General Catalogue of Variable Stars Other Other designations HIC Hipparcos parallaxes RA (2000) Equatorial coordinate right ascension for the equinox 2000.0 D (2000) Equatorial coordinate declination for the equinox 2000.0 RA (1950) Equatorial coordinate right ascension for the equinox 1950.0 D (1950) Equatorial coordinate declination for the equinox 1950.0 Galactic longitude Galactic coordinate longitude Galactic latitude Galactic coordinate latitude Per (d) Period (cycles per day) Amp ( V) Amplitude of light variation (in mag) B B magnitude V V magnitude B-V B-V color index U-B U-B color index 168 R. Zechner Table 1. - continued StarlD Number of identification Mv Absolute magnitude (in Johnson V-filter) b-y Color index b-y (b-y) o Corrected or intrinsic color index ml Parameter ml, ml=(v-b)-(b-y), line blocking dml(b) Dereddened parameter dml(b) cl Parameter cl, cl=(u -v)-(v-b), Balmer jump 0 Beta parameter = H beta - index Epsilon (M) Parameter E (b-y) v sin i Projected rotational velocity in km/s Equinox Equinox ST Spectral type of variable star according to GCVS RV Radial velocity in km/s Q(d) Pulsation constant TEFF The effective temperature in Kelvins log g The decimal logarithm of the surface gravity expressed in cm/s2 M Mass (in M©) L Luminosity (in LQ) R Radius (in RQ) Type Type of variability: DSCT = variable of 5 Set type; DSCTC = Low group of 8 Set variables (A<0.1V); SXPHE = SX Phe type variables; RRC = variables of RR Lyrae type; NOT 5 SCT = Other kinds of variables (f.e. E, EA,...); ??? = unknown Population Population Double Star Double Star Notes Notes Commentary Commentary References Literature references, where information about important features is given. Preliminary 8 Scuti star catalog 169 3. STATISTICS Fig. 1 shows the location of known 8 Scuti stars in the HR- diagram. The dashed lines indicate the observed boundaries of the instability strip. These borders may not be absolute, but are bor- ders to indicate the regions beyond which pulsation is less probable. Wheras a few variables may lie outside these limits, pulsation is much more probable within them. Fig. 2 points out that the values of vsini in high amplitude S Scuti stars are very small (between 20 km/s and 50 km/s) whereas low amplitude variables have a mean value of about lOOkm/s. (b-y)o Fig. 1. Position of 5 Scuti stars in the HR-diagram 250-i vsini (km/s) loo- 0.0 0.2 0.4 0.6 0.8 1.0 Amp (mag) Fig. 2. Full average of the visual amplitude versus rotational velocity. 170 R. Zechner ACKNOWLEDGMENTS. This work is supported by the Aus- trian Fonds zur Förderung der wissenschaftlichen Forschung under project number S7304-AST. REFERENCES Abt H.A., Briggs E.S. 1972, Bibliography of Stellar Radial Velocities, Kitt Peak National Observatory, Arizona Breger M. 1979, 8 Scuti and Related Stars, PASP, 91, 5 Hauck B., Mermilliod M. 1990, uvbyß photoelectric photometric catalogue, A&AS, 86, 107 Kazarovets E. V., Samus N. N. 1990, The 70th Name-List of Variable Stars, IBVS, 3530 Kazarovets E.V., Samus N.N., Goranskij V.P. 1993, The 71st Name-List of Variable Stars, IBVS, 3840 Kholopov P. N., Samus N. N., Frolov M. S. et al. 1985a, General Catalogue of Variable Stars, 4th Edition, Vol. I Kholopov P. N., Samus N. N., Frolov M. S. et al. 1985b, General Catalogue of Variable Stars, 4th Edition, Vol. II Kholopov P. N., Samus N. N., Frolov M. S. et al. 1987a, General Catalogue of Variable Stars, 4th Edition, Vol. III Kholopov P. N., Samus N.N., Durlevich O.V. et al. 1990, General Cata- logue of Variable Stars, 4th Edition, Vol. IV Kholopov P.N., Samus N.N., Kazarovets E.V., Perova N.B. 1985c, The 67th Name-List of Variable Stars, IBVS, 2681 Kholopov P.N., Samus N.N., Kazarovets E.V., Kireeva N.N. 1987b, The 68th Name-List of Variable Stars, IBVS, 3058 Kholopov P.N.; Samus N.N., Kazarovets B.V. et al. 1989, The 69th Name-List of Variable Stars, IBVS 3323 Nicolet B. 1978, Photoelectric photometric catalogue of homogeneous mea- surements in the UBV System, A&AS, 34, 1 Rodriguez E., Lopez de Coca P., Rolland A., Garrido R., Costa V. 1994, 8 Scuti stars: a new revised list, A&AS, 106, 21 Uesugi A., Fukuda I. 1982, Revised Catalogue of Stellar Rotational Velo- cities, Kyoto University, Japan Zechner R. 2000, in Proceedings of the 6th Vienna Workshop in Astro- physics: 8 Scuti and Related Stars, submitted .