The RAdial Velocity Experiment (RAVE): Third Data Release
We present the third data release of the RAdial Velocity Experiment(RAVE) which is the first milestone of the RAVE project, releasing thefull pilot survey. The catalog contains 83,072 radial velocitymeasurements for 77,461 stars in the southern celestial hemisphere, aswell as stellar parameters for 39,833 stars. This paper describes thecontent of the new release, the new processing pipeline, as well as anupdated calibration for the metallicity based upon the observation ofadditional standard stars. Spectra will be made available in a futurerelease. The data release can be accessed via the RAVE Web site.
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UBV(RI)C JHK observations of Hipparcos-selected nearby stars
We present homogeneous, standardized UBV(RI)C photometry forover 700 nearby stars selected on the basis of Hipparcos parallaxes.Additionally, we list JHK photometry for about half of these stars, aswell as L photometry for 86 of the brightest. A number of stars withpeculiar colours or anomalous locations in various colour-magnitudediagrams are discussed.
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UBVRI Photometric Standard Stars Around the Celestial Equator: Updates and Additions
New broadband UBVRI photoelectric observations on theJohnson-Kron-Cousins photometric system have been made of 202 starsaround the sky, and centered at the celestial equator. These starsconstitute both an update of and additions to a previously publishedlist of equatorial photometric standard stars. The list is capable ofproviding, for both celestial hemispheres, an internally consistenthomogeneous broadband standard photometric system around the sky. Whenthese new measurements are included with those previously published byLandolt (1992), the entire list of standard stars in this paperencompasses the magnitude range 8.90 < V < 16.30, and the colorindex range -0.35 < (B - V) < +2.30.
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The effect of activity on stellar temperatures and radii
Context: Recent analyses of low-mass eclipsing binary stars haveunveiled a significant disagreement between the observations andpredictions of stellar structure models. Results show that theoreticalmodels underestimate the radii and overestimate the effectivetemperatures of low-mass stars but yield luminosities that accord withobservations. A hypothesis based upon the effects of stellar activitywas put forward to explain the discrepancies. Aims: In this paper westudy the existence of the same trend in single active stars and providea consistent scenario to explain systematic differences between activeand inactive stars in the H-R diagram reported earlier. Methods: Theanalysis is done using single field stars of spectral types late-K and Mand computing their bolometric magnitudes and temperatures throughinfrared colours and spectral indices. The properties of the stars insamples of active and inactive stars are compared statistically toreveal systematic differences. Results: After accounting for a numberof possible bias effects, active stars are shown to be cooler thaninactive stars of similar luminosity therefore implying a larger radiusas well, in proportions that are in excellent agreement with those foundfrom eclipsing binaries. Conclusions: The present results generalisethe existence of strong radius and temperature dependences on stellaractivity to the entire population of low-mass stars, regardless of theirmembership in close binary systems.Tables 1 and 2 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/478/507
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Further observations of Hipparcos red stars and standards for UBV(RI)C photometry
We present homogeneous and standardized UBV(RI)C JHKphotometry for over 100 M stars selected from an earlier paper on thebasis of apparent photometric constancy. L photometry has been obtainedfor stars brighter than about L = 6. Most of the stars have asubstantial number of UBV(RI)C observations and, it is hoped,will prove useful as red supplementary standards. Additionally, we listJHK photometry for nearly 300 Hipparcos red stars not selected asstandards, as well as L photometry for the brightest stars.
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Absolute magnitudes for late-type dwarf stars for Sloan photometry
We present a new formula for absolute magnitude determination forlate-type dwarf stars as a function of (g-r) and (r-i) for Sloanphotometry. The absolute magnitudes estimated by this approach arebrighter than those estimated by colour-magnitude diagrams, and theyreduce the luminosity function rather close to the luminosity functionof Hipparcos.
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Meeting the Cool Neighbors. VIII. A Preliminary 20 Parsec Census from the NLTT Catalogue
Continuing our census of late-type dwarfs in the solar neighborhood, wepresent BVRI photometry and optical spectroscopy of 800 mid-type Mdwarfs drawn from the NLTT proper-motion catalog. The targets are takenboth from our own cross-referencing of the NLTT Catalogue and the 2MASSSecond Incremental Data Release, and from the revised NLTT compiledrecently by Salim & Gould. All are identified as nearby-starcandidates based on their location in the(mr,mr-Ks) diagram. Three hundred starsdiscussed here have previous astrometric, photometric, or spectroscopicobservations. We present new BVRI photometry for 101 stars, togetherwith low-resolution spectroscopy of a further 400 dwarfs. In total, wefind that 241 stars are within 20 pc of the Sun, while a further 70 liewithin 1 σ of our distance limit. Combining the present resultswith previous analyses, we have quantitative observations for 1910 ofthe 1913 candidates in our NLTT nearby-star samples. Eight hundredfifteen of those stars have distance estimates of 20 pc or less,including 312 additions to the local census. With our NLTT follow-upobservations essentially complete, we have searched the literature for Kand early-type M dwarfs within the sampling volume covered by the 2MASSsecond release. Comparing the resultant 20 pc census against predictednumbers, derived from the 8 pc luminosity function, shows an overalldeficit of ~20% for stellar systems and ~35% for individual stars.Almost all are likely to be fainter than MJ=7, and at leasthalf are probably as yet undiscovered companions of known nearby stars.Our results suggest that there are relatively few missing systems at thelowest luminosities, MJ>8.5. We discuss possible means ofidentifying the missing stars.
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Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog
We complete construction of a catalog containing improved astrometry andnew optical/infrared photometry for the vast majority of NLTT starslying in the overlap of regions covered by POSS I and by the secondincremental Two Micron All Sky Survey (2MASS) release, approximately 44%of the sky. The epoch 2000 positions are typically accurate to 130 mas,the proper motions to 5.5 mas yr-1, and the V-J colors to0.25 mag. Relative proper motions of binary components are measured to 3mas yr-1. The false-identification rate is ~1% for11<~V<~18 and substantially less at brighter magnitudes. Theseimprovements permit the construction of a reduced proper-motion diagramthat, for the first time, allows one to classify NLTT stars intomain-sequence (MS) stars, subdwarfs (SDs), and white dwarfs (WDs). We inturn use this diagram to analyze the properties of both our catalog andthe NLTT catalog on which it is based. In sharp contrast to popularbelief, we find that NLTT incompleteness in the plane is almostcompletely concentrated in MS stars, and that SDs and WDs are detectedalmost uniformly over the sky δ>-33deg. Our catalogwill therefore provide a powerful tool to probe these populationsstatistically, as well as to reliably identify individual SDs and WDs.
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UBV(RI)C photometry of Hipparcos red stars
We present homogeneous and standardized UBV(RI)C photometryfor nearly 550 M stars selected from the Hipparcos satellite data baseusing the following selection criteria: lack of obvious variability (noHipparcos variability flag); δ<+10°(V-I)>1.7 and Vmagnitude fainter than about 7.6. Comparisons are made between thecurrent photometry, other ground-based data sets and Hipparcosphotometry. We use linear discriminant analysis to determine aluminosity segregation criterion for late-type stars, and principalcomponent analysis to study the statistical structure of the colourindices and to calibrate absolute magnitude in terms of (V-I) for thedwarf stars. Various methods are used to determine the mean absolutemagnitude of the giant stars. We find 10 dwarf stars, apparentlypreviously unrecognized (prior to Hipparcos) as being within 25pc,including five within 20pc.
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Revised Coordinates and Proper Motions of the Stars in the Luyten Half-Second Catalog
We present refined coordinates and proper-motion data for the highproper-motion (HPM) stars in the Luyten Half-Second (LHS) catalog. Thepositional uncertainty in the original Luyten catalog is typicallygreater than 10" and is often greater than 30". We have used the digitalscans of the POSS I and POSS II plates to derive more accurate positionsand proper motions of the objects. Out of the 4470 candidates in the LHScatalog, 4323 objects were manually reidentified in the POSS I and POSSII scans. A small fraction of the stars were not found because of thelack of finder charts and digitized POSS II scans. The uncertainties inthe revised positions are typically ~2" but can be as high as ~8" in afew cases, which is a large improvement over the original data.Cross-correlation with the Tycho-2 and Hipparcos catalogs yielded 819candidates (with mR<~12). For these brighter sources, theposition and proper-motion data were replaced with the more accurateTycho-2/Hipparcos data. In total, we have revised proper-motionmeasurements and coordinates for 4040 stars and revised coordinates for4330 stars. The electronic version of the paper5 contains the updated information on all 4470stars in the LHS catalog.
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The Palomar/MSU Nearby Star Spectroscopic Survey. III. Chromospheric Activity, M Dwarf Ages, and the Local Star Formation History
We present high-resolution echelle spectroscopy of 676 nearby M dwarfs.Our measurements include radial velocities, equivalent widths ofimportant chromospheric emission lines, and rotational velocities forrapidly rotating stars. We identify several distinct groups by theirHα properties and investigate variations in chromospheric activityamong early (M0-M2.5) and mid (M3-M6) dwarfs. Using a volume-limitedsample together with a relationship between age and chromosphericactivity, we show that the rate of star formation in the immediate solarneighborhood has been relatively constant over the last 4 Gyr. Inparticular, our results are inconsistent with recent large bursts ofstar formation. We use the correlation between Hα activity and ageas a function of color to set constraints on the properties of L and Tdwarf secondary components in binary systems. We also identify a numberof interesting stars, including rapid rotators, radial velocityvariables, and spectroscopic binaries. Observations were made at the 60inch telescope at Palomar Mountain, which is jointly owned by theCalifornia Institute of Technology and the Carnegie Institution ofWashington.
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The u'g'r'i'z' Standard-Star System
We present the 158 standard stars that define the u'g'r'i'z' photometricsystem. These stars form the basis for the photometric calibration ofthe Sloan Digital Sky Survey. The defining instrument system andfilters, the observing process, the reduction techniques, and thesoftware used to create the stellar network are all described. Webriefly discuss the history of the star selection process, thederivation of a set of transformation equations for theUBVRCIC system, and plans for future work.
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The Palomar/MSU Nearby Star Spectroscopic Survey.II.The Southern M Dwarfs and Investigation of Magnetic Activity
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996AJ....112.2799H&db_key=AST
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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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The Palomar/MSU Nearby-Star Spectroscopic Survey. I. The Northern M Dwarfs -Bandstrengths and Kinematics
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....110.1838R&db_key=AST
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Statistical studies of visual double and multiple stars. II. A catalogue of nearby wide binary and multiple systems.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1994RMxAA..28...43P&db_key=AST
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The importance of surface inhomogeneities for K and M dwarf chromospheric fluxes
We present published and archived spectroscopic and spectrophotometricdata of H-alpha, Ca II, Mg II, and X-rays for a large sample of K and Mdwarfs. The data set points to the importance that surfaceinhomogeneities have in the flux luminosity diagrams in these late-typedwarfs, irrespective of whether the Balmer lines are in emission orabsorption. Although supporting the fact that cooler stars exhibitincreasing levels of surface activity, evident through an increasingincidence of Balmer emission, surface inhomogeneities, or variations inthe local temperature and density structure, at the chromospheric level,dominate the total Ca II and Mg II fluxes. We show that the flux-fluxand luminosity-luminosity relations indicate differing extents ofinhomogeneity from the chromosphere through to the corona. A goodcorrelation between Ca II and Mg II fluxes indicates that they areformed in overlapping regions of the chromosphere, so that thecontribution of surface inhomogeneities is not evident from thisparticular flux-flux diagram. In the region of the upper chromospherethrough to the transition and corona, the correlation between Ly-alphaand X-ray fluxes indicates regions with similar levels of arealinhomogeneity. This appears to be uncorrelated with that at thechromospheric level.
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Infrared colors of low-mass stars
A total of 322 red dwarf stars are studied in a review of IR IJHKphotometry to discern chromospheric activity and kinematic dataregarding metallicity effects in the IR color:color diagrams. Themetallicity variations are employed to assess changes in the H(-)continuum opacity and water-vapor characterizations. The stars areclassified in terms of metal-richness with five categories includingyoung disk, old disk, and halo types with attention given to the inverserelationship between metallicity and water-band absorption strength. Theresults include IR photometric parallax relations for each metallicitygroup and absolute magnitudes for single stars as well as temperatures,intrinsic colors, and spectral types. The body of data is useful forconstraining models of the interiors and atmospheres of this class ofstars.
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UBVRI photometric standard stars in the magnitude range 11.5-16.0 around the celestial equator
UBVRI photoelectric observations have been made on theJohnson-Kron-Cousins photometric system of 526 stars centered on thecelestial equator. The program stars within a 298 number subset havesufficient measures so that they are capable of providing, fortelescopes of intermediate and large size in both hemispheres, aninternally consistent homogeneous broadband standard photometric systemaround the sky. The stars average 29 measures each on 19 nights. Themajority of the stars in this paper fall in the magnitude range11.5-16.0, and in the color range -0.3 to +2.3.
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VRI photometry of late dwarf common proper motion pairs
VRI photometry and photometric distance moduli are presented for 266late dwarf common proper motion pairs. From the distance modulusdifferences between the components of each pair, it is inferred that atleast 56 percent of the pairs contain one or more additional stellarcomponents. The maximum separation of M dwarf binaries appears to be ofthe order 10,000-20,000 AU.
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Catalogue of Variable or Suspected Stars Nearby the Sun
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990A&AS...85..971P&db_key=AST
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BVRI photometry of the Gliese Catalogue stars
Photoelectri BVRI photometry on the Cousins (Kron-Cape) system has beenobtained for many of the southern faint stars in the Gliese Catalog(1969). This extends the work of Cousins (1980) and provides a uniformset of data for the nearby stars. Several red dwarfs are noted, whichwere used to define the red end of the Cousins system.
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H-alpha versus X-ray luminosity in dwarf M stars
A power-law correlation is presented between the excess chromosphericH-alpha emission and the coronal X-ray emission for a group of dM anddMe stars. This excess emission was calculated by subtracting themaximum (i.e., saturated) observed H-alpha absorption equivalent widthfor a star of a similar color. Heating of the chromosphere through X-rayback-heating is not the dominant component of chromospheric heating indM stars, although in the very active late-type stars its contributioncould be about 50 percent.
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The infrared luminosity function for low-mass stars
IR observational luminosity functions are presented for M dwarfs towardsthe South Galactic Pole and the Hyades cluster. A compilation of VRIJHKdata is given for 200 parallax stars. Two-color NIR/IR diagrams of thedata are used to demonstrate metallicity and gravity effects. It isshown that I-J is the purest temperature color index. The corrections tothe luminosity functions that are necessary to allow for magnitudeerrors (Malmquist effects) are discussed. It is found that there is arise in the luminosity function and the mass function for stars in thesolar neighborhood with masses close to the hydrogen-burning limit.
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Chromospheric activity, kinematics, and metallicities of nearby M dwarfs
Attention is given to the results of more than 1000 observations ofabout 200 Gliese (1969) catalog M dwarfs, whose BVRIJHK photometry isbelieved to be accurate to 0.015 mag in each bandpass. An analysis ofthese data indicates that the H-alpha equivalent widths are a usefulchromospheric indicator for M dwarfs; as the chromosphere increases instrength, the H-alpha absorption equivalent width first increases, thendecreases, and H-alpha finally goes into emission, as predicted by Gramand Mullan (1979) for M dwarf chromospheres. The present JHK photometryis used to identify stars with metallicities that are significantlydifferent from that of the sun. It is noted that dMe stars in thissample generally have young disk motions, are more luminous than dMstars of the same color, and have B-V colors that are too blue for theirV-I color.
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Dwarf K and M stars of high proper motion found in a hemispheric survey
A recently completed visual/red spectral region objective-prism surveyof more than half the sky found some 2200 dwarf K and M stars ofnegligible proper motion (Stephenson, 1986). The present paper adds the1800-odd spectroscopically identified dwarfs that did prove to havesignificant proper motions. About half of these had previous spectralclassifications of some sort, especially by Vyssotsky (1952, 1956). Forthe great majority, the present coordinates are more accurate thanprevious data. The paper includes about 50 stars with unpublishedparallaxes, likely to have parallaxes of 0.05 arcsec or more. Combiningthe present data with the first paper suggests that the number oflow-proper-motion stars in that paper was not unreasonable.
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G. P. Kuiper's spectral classifications of proper-motion stars
Spectral classifications are listed for over 3200 stars, mainly of largeproper motion, observed and classified by Kuiper during the years1937-1944 at the Yerkes and McDonald Observatories. While Kuiper himselfpublished many of his types, and while improved classifications are nowavailable for many of these stars, much of value remains. For many ofthe objects, no other spectral data exist.
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Predicted infrared brightness of stars within 25 parsecs of the sun
Procedures are given for transforming selected optical data intoinfrared flux densities or irradiances. The results provide R, T(eff)blackbody approximations for about 2000 of the stars in Woolley et al.'sCatalog of Stars (1970) within 25 pc of the sun, and additional whitedwarfs, with infrared flux densities predicted for them at ninewavelengths from 2.2 to 101 microns including the Infrared AstronomySatellite bands.
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Spectral Types of M Dwarf Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJS...28....1J&db_key=AST
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Luminosities and temperatures of M dwarf stars from infrared photometry
Bolometric magnitudes for a large number of M type dwarf stars, obtainedby broadband infrared photometry at 1.65, 2.2, and 3.5 microns, arereviewed. The data obtained indicate that one parameter is sufficient todescribe the blanketing in all of the UBVRI bands for all types of Mdwarfs. In general, late M dwarfs seem to have lower effectivetemperatures than are predicted by theoretical models.
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INHABITED SKY
