A revised catalogue of delta Sct stars
An extensive and up-dated list of delta Sct stars is presented here.More than 500 papers, published during the last few years, have beenrevised and 341 new variables have been added to our last list, sixyears ago. This catalogue is intended to be a comprehensive review onthe observational characteristics of all the delta Sct stars known untilnow, including stars contained in earlier catalogues together with othernew discovered variables, covering information published until January2000. In summary, 636 variables, 1149 references and 182 individualnotes are presented in this new list. Tables 1 and 2 will be accessibleonly in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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MSC - a catalogue of physical multiple stars
The MSC catalogue contains data on 612 physical multiple stars ofmultiplicity 3 to 7 which are hierarchical with few exceptions. Orbitalperiods, angular separations and mass ratios are estimated for eachsub-system. Orbital elements are given when available. The catalogue canbe accessed through CDS (Strasbourg). Half of the systems are within 100pc from the Sun. The comparison of the periods of close and widesub-systems reveals that there is no preferred period ratio and allpossible combinations of periods are found. The distribution of thelogarithms of short periods is bimodal, probably due to observationalselection. In 82\% of triple stars the close sub-system is related tothe primary of a wide pair. However, the analysis of mass ratiodistribution gives some support to the idea that component masses areindependently selected from the Salpeter mass function. Orbits of wideand close sub-systems are not always coplanar, although thecorresponding orbital angular momentum vectors do show a weak tendencyof alignment. Some observational programs based on the MSC aresuggested. Tables 2 and 3 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Spectroscopic survey of delta Scuti stars. I. Rotation velocities and effective temperatures
Projected rotational velocities and effective temperatures for 68 deltaSct stars as well as 41 non-variable stars of similar spectral type andluminosity are presented here. The rotational velocities have beencalculated following the method developed in \cite[Gray (1992)]{ref38}and effective temperatures have been derived using the Balmer lineprofiles. The temperatures obtained from this method are shown to be inreasonable agreement with those calculated using the Infrared FluxMethod (IRFM) or spectrophotometric methods. This result has allowed usto use our temperatures to compare different uvby beta photometriccalibrations. We find that the calibration given by \cite[Moon \&Dworetsky (1985)]{ref72} is the most consistent. In the second part ofthis paper we have studied the relation between the pulsationalproperties (periods and amplitudes) and the physical parameters (v sin iand Teff). Where pulsation modes have been determined, thelow amplitude $\delta$ Scutis tend to be multimode (radial andnon-radial) pulsators, consistent with the theory that non-linearcoupling between modes acts to limit the amplitude in these stars. Wehave compared the distribution of v sin i for low amplitude $\delta$Scutis and non-variable stars. This shows the $\delta$ Scutis have abroader distribution in v sin i suggesting that a high rotation velocitymay favour pulsation. We find that the large amplitude delta Scuti starstend to have longer periods, cooler temperatures and lower rotationvelocities. Given that the large amplitude stars are also relativelyrare all the above are consistent with the hypothesis that these starsare more evolved (sub-giants) than the low amplitude delta Scutis (mainsequence or early post-main sequence).
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Luminosity and related parameters of δ Scuti stars from HIPPARCOS parallaxes. General properties of luminosity.
The absolute magnitudes of δ Scuti stars derived from parallaxesmeasured by the Hipparcos astrometric satellite are discussed andcompared with the previous estimates based on photometric uvbyβindices. There are significant differences which are related tophotometric effects of metallicity and rotational velocity, but thepossible effect of a close companion on the measured apparent magnitudeshould be also taken into account. The possibility of differentgroupings of δ Scuti stars based on the absolute magnitudes isbriefly discussed. Some high amplitude δ Scuti stars withintermediate or normal metallicity and small and uncertain parallax haveapparently a very low luminosity; this could be a systematic effectrelated to the observational errors.
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Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
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A catalogue of variable stars in the lower instability strip.
Identifications, positions, photometry, spectra, some pulsationalfeatures, other astrophysical parameters and literature for 302pulsating variable stars in the lower instability strip, near the ZAMS,are given. About 185 stars have near homogeneous photometric informationin the Stroemgren's uvby-β photometric system. Thiscatalogue/database covers information published until November 1993.
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Stroemgren photometry of F- and G-type stars brighter than V = 9.6. I. UVBY photometry
Within the framework of a large photometric observing program, designedto investigate the Galaxy's structure and evolution, Hβ photometryis being made for about 9000 stars. As a by-product, supplementary uvbyphotometry has been made. The results are presented in a cataloguecontaining 6924 uvby observations of 6190 stars, all south ofδ=+38deg. The overall internal rms errors of one observation(transformed to the standard system) of a program star in the interval6.5
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δ Scuti stars: a new revised list
An extensive and up to date list of δ Sct stars is presented. Thiscatalogue is intended to be a comprehensive review of observationalcharacteristics of all the δ Sct stars known until now, includingstars contained in earlier catalogues together with other new discoveredvariables, covering information published until November 1993. Globalinformation in the form of histograms and diagrams are also shown.
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Empirical P-L-C relation for Delta Scuti stars - A catalogue
An extensive and up-to-date list of 192 Delta Scuti stars is presented.Empirical period - luminosity - color (P-L-C) relations are obtained forthe four lowest modes corresponding to radial pulsations. Agreement withpredicted values indicates that, in general, both Stroemgren photometriccalibration and pulsation theory work well for these stars.
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Orbital binaries with variable components
Published observational data are compiled for 171 binary systems forwhich (1) orbital parameters have been computed and (2) one or bothcomponents are known or suspected to exhibit intrinsic variability. Theselection criteria for the catalog are discussed; the data are presentedin a large table; and brief notes on the unusual characteristics ofspecific binaries are provided.
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Maximum separations among cataloged binaries
The paper classifies many of the widest common-motion binaries listed inthe Aitken catalog and list 72 physical pairs with known photoelectricphotometry, 31 physical pairs without good photometry, and 27 opticalpairs. As a function of primary types, the physical systems have upperlimits to their separations that are exceeded by some of the opticalpairs. The fact that optical pairs occur with larger separations impliesthat the limits are real ones and not just catalog limitations. Thoselimits (in AU) are expressed by 2500 M1 exp 1.54 for B5-KO main-sequenceprimaries. The same limits hold for the Trapezium and hierarchicalsystems studied previously.
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Quasi-160-minute oscillation period of Delta Scuti stars
The resonance power spectrum (or commensurability spectrum) computed for217 Delta Scuti stars indicates that the dominant (most commensurate)period for the total set of oscillation periods of these stars is 162.2+ or - 2.8 min. Within the error limits, this period coincidesapproximately with the 160-min period of global oscillations of the sun.
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Population I pulsating stars. III - Period-Evolutionary mass(-colour) relations
Evolutionary masses of Population I pulsating stars (89 Delta Scutivariables and 155 classical Cepheids are investigated in Iben's andPaczynski's systems of tracks. The evolutionary masses are larger in thelatter system than in the former. The uncertainty of the evolutionarymass of a star is estimated, when various evolutionary phases arepossible for this star (a smaller evolutionary mass corresponds to alater phase). Semi-empirical period-evolutionary mass-color (P-Me-C) andperiod-evolutionary mass (P-Me) relations are derived for various modes,groups of stars, color indices (and effective temperature), andevolutionary phases. For Delta Scuti stars, the uncertainty ofevolutionary masses calculated from the P-Me relations for differentmodes, is estimated. The improvement of the evolutionary mass accuracyis estimated, when a P-Me-C relation is used instead of thecorresponding P-Me relation. The theoretical and semi-empirical periodratios of radial pulsations derived from the P-Me relations for DeltaScuti stars, are compared. There is relatively good agreement betweenthe P-Me relations for the two types of Population I pulsating stars,but a 'gap' exists between them.
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Population I pulsating stars. II - Period-age (-colour) relations
Ages corresponding to various evolutionary phases of population Ipulsating stars (89 Delta Scuti variables and 155 classical cepheids)are interpolated in the evolutionary track systems of Iben (1967) andPaczynski (1970). The stellar ages are considerably less in the lattersystem than in the former one. The undertainty of the age of a star isestimated when various evolutionary phases are possible for this star (agreater age corresponds to a later phase). Semiempiricalperiod-age-color (P-t-C) and period-age (P-1) relations are derived forvarious modes, groups of stars, color indices (and effectivetemperature), and evolutionary phases. For Delta Scuti stars, theuncertainty of ages calculated from the P-t relations for differentmodes, is estimated. Theoretical P-t-C and P-t relations for Delta Scutistars are obtained and compared with semiempirical relations (such acomparison of P-t relations is performed for classical cepheids too).The improvement of the age accuracy is estimated when a P-t-C relationis used instead of the corresponding P-t relation. The theoretical andsemiempirical period ratios of radial pulsations, derived from the P-trelations for Delta Scuti stars, are compared. There is relatively goodagreement between the P-t relations for the two types of population Ipulsating stars, but a 'gap' exists between them.
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Radial pulsation modes as a possible cause for the heterogeneity of the Delta Scuti stars
On the basis of observational data (Breger, 1979), a radial pulsationmode of 83 Delta Scuti stars is estimated in two ways. These stars canpulsate in four lowest modes - F, 1H, 2H, 3H - and, perhaps, in 4H and5H. An earlier suggestion that the apparent heterogeneity of theseobjects in both the period luminosity plane and the period-frequencydistribution may be explained by means of pulsations in various modes -is confirmed. Semiempirical period-luminosity relations for the fourlowest modes are derived and the semiempirical period ratios arecompared with the theoretical ones.
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Spectral Classification of Select Delta-Scuti Stars - Part Three
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983RMxAA...8...45O&db_key=AST
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Revised list of pulsating stars with ultra-short periods
A comprehensive list of 178 known Delta Scuti and RR Lyrae-stars ispresented. Using this revised list a HR diagram for these ultra shortperiod pulsating stars is plotted and the blue and red edges of theresultant instability strip are determined. Selection effects arediscussed, and the PLC relationship of Breger (1979) is tested usingdata from this list. Stars lying outside the defined instability regionare discussed.
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Properties of Am, Delta Del and Delta SCT stars in the VBLUW system
The spread with respect to the main sequence in the two-color diagramsfor 115 Am, Delta Del and Delta Sct, for which VBLUW photometricobservations have been obtained, is primarily attributed to gravityeffects. Exceptions to this rule can be recognized from a comparison oftheir positions in these diagrams and in the reddening-independentdiagram L-U/B-L, where some Delta Sct stars have experienced relativelyhigh reddenings, while others are presumably metal-poor. It is notedthat gravities and temperatures compare satisfactorily with those ofDavis Philip et al. (1976), which were based on uvby-beta photometry.
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The radial pulsation modes of the Delta Scuti stars, and their nonuniform period distribution
From Breger's 1979 survey of the observational data for the Delta Sctvariables, radial pulsation modes are assigned to 83 of these stars.They can pulsate in the four lowest modes: F, 1H, 2H, 3H, and perhapsalso in 4H and even 5H. Confirming the author's earlier suggestion, theapparent nonuniformity in the distribution of Delta Sct stars both withrespect to period and in the period-luminosity diagram may naturally beattributed to pulsation in differing modes. Semiempirical (P, L)relations are derived for the four lowest modes, and the semiempiricaland theoretical period ratios are compared. Several statisticalrelationships are obtained, and in certain cases criteria are proposedfor determining the radial-pulsation mode.
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Delta Scuti and related stars
An extensive review is given of the current status of our knowledge ofthe stars in the lower instability strip. Current problems areemphasized. Particular attention is given to the following areas: theconfusion concerning naming and the implied astrophysical properties(often erroneous), single and multiple periods, the effect of rotationand metallicism on pulsation, the nature of the so-called dwarfcepheids, and pulsation in Ap stars. Various reports of unusal andstrange effects are also discussed with personal, possibly biasedjudgment on their reality.
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The classification of intrinsic variables. VIII - Ultrashort period Cepheids
The photometric and astrometric data for ultrashort-period Cepheids withmaximum visual magnitudes brighter than 11.5 are collected anddiscussed. Most of these variables are high-mass, little-evolved starswhich, in the halo and disk populations, are blue stragglers. Theluminosities are calibrated from membership in disk and halo populationgroups; the visual magnitude equals 8(1-/c1/sub c) for disk stars, where(C1)sub c is a reddening- and temperature-free parameter.
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Intermediate Band and Hbeta Photometry of Ultrashort Period Cepheids
Not Available
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Empirical P-L-C Relations for Delta Scuti Stars
Separate P-L-C relations have been empirically derived by sampling the ~Scuti stars according to their pulsation modes. The results based onthese relations have been compared with those estimated from the modelbased P-L-C relations and the other existing empirical P-L--C relations.It is found that a separate P-L-C relation for each pulsation modeprovides a better correspondence with observations
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Period-luminosity-color relations and pulsation modes of pulsating variable stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975ApJ...200..343B&db_key=AST
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Intermediate Band Photometry of BB Lyrae Stars. II. Colors of RR Lyrae and Ultra-Short Period Variables
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973ApJS...25..487J&db_key=AST
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Delta SCT stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&A....23..221B&db_key=AST
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58th Name-List of Variable Stars
Not Available
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Pulsation of models in the lower part of the cepheid instability strip and properties of AI Vel and del SCT variables.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972A&A....17..367P&db_key=AST
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Short period variable stars. IV. : periods of del SCT stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972A&A....16...38V&db_key=AST
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INHABITED SKY
