V/80ivo://CDS.VizieR/V/80CDSProsser C.F.2012-11-12T15:44:53Z2001-07-13T16:10:58ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.fropen-star-clustersstellar-massesproper-motionsspectroscopyThis catalog contains the tabulated results of a combined astrometric, photometric, and spectroscopic search for low-mass members in the intermediate-age open cluster Alpha Persei. It contains information on 132 new members and likely members, and 16 uncertain members of Alpha Per. The new membership information suggested to the author a revised age of the cluster to approximately 8x10+7yr. Tabulated data include AP number, VBI photometry, 1950 coordinates, relative proper motions with errors, H-alpha equivalent widths, and spectral type. Included are the individual membership determinations, based on H-alpha emission, spectral type, and echelle spectra data. The photometric data were obtained with the Lick Obs. 1-m Nickel Telescope using a TI 500x500 pixel CCD in B, V, and I bands. Low dispersion CCD spectra centered on H-alpha for candidates whose V-I photometry indicated likely membership using the Lick 1-m Nickel and 3-m Shane telescopes. High-dispersion echelle spectra were obtained for many bright candidates using the Hamilton echelle spectrographic with the Shane and Coude auxiliary telescopes. Introduction: van den Bergh & Sher (1960) found from studying several open clusters that in general the faint end of the cluster luminosity function decreased or remained constant down to the level of observation. If true, the observed cluster luminosity functions are unable to account for the luminosity function of nearby field stars which increases to faint magnitudes. One possible solution is that additional unidentified low-mass stars exist in most (or all) open clusters. Recent studies in the Hyades (Weis & Hanson 1988AJ.....96..148W, Griffin et al. 1988AJ.....96..172G, Stauffer 1982AJ.....87..899S), Pleiades (Stauffer et al. 1991AJ....101..980S, Prosser et al. 1991AJ....101.1361P), and Praesepe (Mermilliod et al. 1990A&A...235..114M, Jones & Stauffer 1991AJ....102.1080J) have identified faint candidate members. It is the aim of this study to determine the existence, and some of the properties, of the low-mass membership in the open cluster Alpha Persei. Alpha Per was chosen for study because of the limited information on low-mass membership, because it is nearby (which enables both proper motion analysis and observation of low-mass candidates), because no other clusters of the same relatively youthful age have been studied completely, and because of the existence of the photographic plate material needed for the proper motion analysis. After a brief review of the history and previous work in this cluster, the proper motion survey of this study is described. This is accompanied by a description of the CCD photometry and spectroscopy programs employed to aid in identifying cluster members. A review of current information on previous members and possible members is also given, followed by a section presenting the new members and candidate members found in this study. An analysis of some cluster properties including luminosity function, age, spatial distribution of members, reddening, H-alpha emission strengths, and rotational velocity distribution is presented. Finally, the last section provides a general review of the results found in Alpha Per.1992AJ....103..488Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/V/80CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/68 : Positions and Proper Motions in alpha Per cluster (Fresneau 1980)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=V/80https://vizier.iucaa.in/viz-bin/VizieR-2?-source=V/80http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=V/80https://vizier.cds.unistra.fr/viz-bin/votable?-source=V/80https://vizier.iucaa.in/viz-bin/votable?-source=V/80http://vizieridia.saao.ac.za/viz-bin/votable?-source=V/80GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table V/80/table4 (Table 4: HE candidates (Heckmann et al. 1956AN....283..109H))https://vizier.cds.unistra.fr/viz-bin/conesearch/V/80/table4?https://vizier.iucaa.in/viz-bin/conesearch/V/80/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/V/80/table4?GETtext/xml+votable180.050000true46.76682951.2947150.005555555555555556Cone search capability for table V/80/table6 (Table 6: Fresneau's suggested HE members)https://vizier.cds.unistra.fr/viz-bin/conesearch/V/80/table6?https://vizier.iucaa.in/viz-bin/conesearch/V/80/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/V/80/table6?GETtext/xml+votable180.050000true47.04520848.9189810.005555555555555556Cone search capability for table V/80/table10 (Table 10: New AP membership information)https://vizier.cds.unistra.fr/viz-bin/conesearch/V/80/table10?https://vizier.iucaa.in/viz-bin/conesearch/V/80/table10?http://vizieridia.saao.ac.za/viz-bin/conesearch/V/80/table10?GETtext/xml+votable180.050000true49.38056248.8642060.0055555555555555565/440 442 443 773 775 784 785 786 6/1719 1725 1726 1727 1739 1740 1742 1743 1765 1766 1767 1784 1786 3089 3091 3096 3097 3099 3124 3127 3148 31683.322582951404819e-19 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/V/80?format=asciiOpticaldefaultV/80/table4Table 4: HE candidates (Heckmann et al. 1956AN....283..109H)notesNotesmeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHEStar identificationmeta.id;meta.mainintHEn[N ]meta.notecharVmagV magnitudemagphot.mag;em.opt.Vfloatu_Vmag[: ]V magnitude uncertainty flagmeta.code.errorcharB-VB-V color indexmagphot.color;em.opt.B;em.opt.VfloatBDBD (Cat. <I/122>) designationmeta.idcharRA1950Right ascension (1950)pos.eq.ra;meta.mainDE1950Declination (1950)pos.eq.dec;meta.mainRVKr?Radial velocity from Kraftkm/sspect.dopplerVelocfloatnullableRVo[0-9 . :+-] Other radial velocitykm/sspect.dopplerVeloc;pos.heliocentricchare_RVo?Error in other radial velocitykm/sstat.errorfloatnullablel_Vrot[><= ] Limit indication for rot. velocitymeta.code.errorcharVrot?Rotational velocity from echelle spectrakm/sphys.veloc.rotatintnullableu_Vrot[: ]Rotational velocity uncertainty flagmeta.code.errorcharref_1?Reference 1meta.ref;pos.frameintnullableref_2?Reference 2meta.ref;pos.frameintnullablemphot[YN? ] HE membership from photometrymeta.code.membercharmesche[YN? ] HE membership from echelle spectrameta.code.membercharmli[YWK? ] HE membership from LImeta.code.membercharmfinal[YN? ] Final HE membership determinationmeta.code.memberchar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data)pos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data)pos.eq.decnullableindexedV/80/table6Table 6: Fresneau's suggested HE membersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHEStar identificationmeta.id;meta.mainintVmagV magnitudemagphot.mag;em.opt.VfloatB-VB-V color indexmagphot.color;em.opt.B;em.opt.VfloatV-IV-I color indexmagphot.color;em.opt.V;em.opt.IfloatvNumber of V observationsmeta.numberintbNumber of B observationsmeta.numberintiNumber of I observationsmeta.numberintBDBD designation (Cat. <I/122>)meta.idcharRA1950Right ascension (1950)pos.eq.ra;meta.mainDE1950Declination (1950)pos.eq.dec;meta.mainFprobFresneau's membership probabilitystat.probabilityfloatmBVI[YN? ] Membership based on BVImeta.code.membercharmuvby[YNPM? ] Membership based on uvby-beta photometry by Trullols et al. (1989A&AS...81...47T)meta.code.membercharRV?Radial velocity from echelle spectrakm/sspect.dopplerVelocfloatnullablee_RV?Error in radial velocitykm/sstat.errorfloatnullablel_Vrot[>< ] Limit indication for rot. velocitymeta.code.errorcharVrot?Rotational velocity from echelle spectrakm/sphys.veloc.rotatintnullableu_Vrot[: ] Rotational velocity uncertaintymeta.code.errorcharmfinal[YN? ] Final HE membership determinationmeta.code.membercharnotesNotesmeta.notechar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data)pos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data)pos.eq.decnullableindexedV/80/table10Table 10: New AP membership informationSp?MK Spectral Typesrc.spTypecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAPAP numbermeta.id;meta.mainintprimaryVmagV magnitudemagphot.mag;em.opt.VfloatB-V?B-V color indexmagphot.color;em.opt.B;em.opt.VfloatnullableV-IV-I color indexmagphot.color;em.opt.V;em.opt.IfloatvNumber of V obs.meta.numberintbNumber of B obs.meta.numberintiNumber of I obs.meta.numberintRA1950Right ascension (1950)pos.eq.ra;meta.mainDE1950Declination (1950)pos.eq.dec;meta.mainpmXRelative proper motion in X directionarcsec/yrpos.pm;pos.dirCosfloatpmYRelative proper motion in Y directionarcsec/yrpos.pm;pos.dirCosfloate_pmXProper motion error in X direction10mas/yrstat.errorfloate_pmYProper motion error in Y direction10mas/yrstat.errorfloatEW[0-9 .-]? H-alpha equiv. width (angstroms)0.1nmspect.line.width;em.line.Halphacharmphot[YN? ] phot. membership determinationmeta.code.membercharmhalph[YNWAF? ]? H-alpha membership determinationmeta.code.membercharmspect[YN? ]? Spectral membership determinationmeta.code.membercharmesche[YN? ]? Echelle spect. determinationmeta.code.membercharmfinal[Y? ] Final membership determinationmeta.code.membercharnotesNotesmeta.notechar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data)pos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data)pos.eq.decnullableindexedV/80/table11Table 11: Velocities of new AP starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAPAP numbermeta.id;meta.mainintVmagV magnitudemagphot.mag;em.opt.VfloatB-V?B-V color indexmagphot.color;em.opt.B;em.opt.VfloatnullableV-IV-I color indexmagphot.color;em.opt.V;em.opt.IfloatRV?Heliocentric radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloatnullablee_RV?Error in radial velocitykm/sstat.errorfloatnullableVrot[0-9><-: ] Rotational velocity (Vsini)km/sphys.veloc.rotatcharLi[STRYWK?- ] Presence of Li 6707 linemeta.codecharmescheMembership based on echelle spectrameta.code.membercharNotes?Notes on binary status, spectrum, velocitymeta.notechar