Chromospheric Activity of Southern Stars from the Magellan Planet Search Program
I present chromospheric-activity measurements of ~670 F, G, K, and Mmain-sequence stars in the Southern Hemisphere, from ~8000 archivalhigh-resolution echelle spectra taken at Las Campanas Observatory since2004. These stars were targets from the Old Magellan Planet Search, andare now potential targets for the New Magellan Planet Search that willlook for rocky and habitable planets. Activity indices (S values) arederived from Ca II H and K line cores and then converted to the MountWilson system. From these measurements, chromospheric (logR'HK) indices are derived, which are then used as indicatorsof the level of radial-velocity jitter, age, and rotation periods thesestars present.Based on observations obtained with the Magellan Telescopes, operated bythe Carnegie Institution, Harvard University, University of Michigan,University of Arizona, and the Massachusetts Institute of Technology.
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Accurate Coordinates and 2MASS Cross Identifications for (Almost) All Gliese Catalog Star
We provide precise J2000, epoch 2000 coordinates, andcross-identifications to sources in the 2MASS Point Source Catalog fornearly all stars in the Gliese, Gliese-Jahreiss, and Woolley catalogs ofnearby stars. The only Gliese objects where we were not successful aretwo Gliese sources that are actually QSOs; two proposed companions tobrighter stars, which we believe do not exist; four stars included inone of the catalogs but identified there as only optical companions; oneprobable plate flaw; and two stars that simply remain unrecovered. Forthe 4251 recovered stars, 2693 have coordinates based on Hipparcospositions, 1549 have coordinates based on 2MASS data, and 9 havepositions from other astrometric sources. All positions have beencalculated at epoch 2000 using proper motions from the literature, whichare also given here.
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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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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
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Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample
We are obtaining spectra, spectral types, and basic physical parametersfor the nearly 3600 dwarf and giant stars earlier than M0 in theHipparcos catalog within 40 pc of the Sun. Here we report on resultsfor 1676 stars in the southern hemisphere observed at Cerro TololoInter-American Observatory and Steward Observatory. These resultsinclude new, precise, homogeneous spectral types, basic physicalparameters (including the effective temperature, surface gravity, andmetallicity [M/H]), and measures of the chromospheric activity of ourprogram stars. We include notes on astrophysically interesting stars inthis sample, the metallicity distribution of the solar neighborhood, anda table of solar analogs. We also demonstrate that the bimodal nature ofthe distribution of the chromospheric activity parameterlogR'HK depends strongly on the metallicity, andwe explore the nature of the ``low-metallicity'' chromosphericallyactive K-type dwarfs.
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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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The Liverpool-Edinburgh high proper motion survey
We present a catalogue of 6206 stars which have proper motions exceeding0.18arcsec yr-1 with an R-band faint magnitude limit of 19.5mag. This catalogue has been produced using SuperCOSMOS digitized R-bandESO and UK Schmidt Plates in 131 Schmidt fields covering more than 3 000square degrees (>7.5% of the whole sky) at the South Galactic Cap.The survey is >= 90% complete within the nominal limits of the LuytenTwo Tenths Catalogue of mR <= 18 .5 mag and 0.2 <= mu<=2.5arcsec yr-1, and is >= 80% complete formR <= 19 .5 mag and mu <=2 .5arcsec yr-1.Catalogue is only available in electronic form at the CDS via anonymousftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/397/575
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Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
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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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Ca II H and K Filter Photometry on the UVBY System. II. The Catalog of Observations
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....109.2828T&db_key=AST
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The general catalogue of trigonometric [stellar] paralaxes
Not Available
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Not Available
Not Available
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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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UBV (RI)c photometry of faint nearby stars.
Not Available
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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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New light on faint stars. I - The luminosity function in the solar neighbourhood
From photoelectric photometry of red dwarf stars identified in anobjective prism survey, a magnitude-limited complete sample has beendefined. Applying photometric parallaxes, calibrated for theKron-Cousins system by observations of trigonometric parallax stars,this sample is used to determine the space densities of stars withabsolute magnitudes between + 7 and + 12. The resultant luminosityfunction is consistent with the Luyten and Wielen functions for thesolar neighbourhood. An analysis of the stellar kinematics shows littlesignificant evidence of a substantial local population of low spacemotion M-dwarfs.
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Photometry of Southern Hemisphere red dwarf stars
Results are presented for a photometric investigation of aspectroscopically selected sample of red dwarf stars in the SouthernHemisphere. Absolute magnitudes and distances for the stars areestimated from broadband red colors. Three stars which may besubluminous are identified, as are several stars which may be within 25pc. The tangential velocity and velocity dispersion of the sample aresimilar to values found in other studies of nearby late-type stars.
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Optical polarization of stars of galactic latitudes b-45 degres.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...23..125S&db_key=AST
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The space density and kinematics of dwarf M stars
The results of an objective-prism survey for dwarf stars, K7 and later,are presented. One hundred twenty-one red sensitive plates covering 1720sq. degrees of the southern sky were obtained with the Curtis Schmidttelescope at C.T.I.O. The resulting luminosity function rises from log N+ 10 = 7.9 at MV = 8 to about 8.7 at MV = 11 and12. About 75% of the dwarfs in this survey are identified with BPMstars, but inserting the proper motions given into the equations of themethod of mean absolute magnitudes yields values of MB aboutthree magnitudes brighter than the spectral types would indicate. Thatthe method of mean absolute magnitudes appears to be calibrated on starsof higher than average proper motion lends credence to the luminosityfunction result. A galactic mass density is found for the dwarfsconsidered.
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UBV Photometry of 500 Southern Stars [erratum: 1973MNSSA..32...48C]
Not Available
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Photoelectric Three Colour Magnitudes for Southern Stars
Not Available
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