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XID II: Statistical Cross-Association of ROSAT Bright Source Catalog X-ray Sources with 2MASS Point Source Catalog Near-Infrared Sources
The 18,806 ROSAT All Sky Survey Bright Source Catalog (RASS/BSC) X-raysources are quantitatively cross-associated with near-infrared (NIR)sources from the Two Micron All Sky Survey Point Source Catalog(2MASS/PSC). An association catalog is presented, listing the mostlikely counterpart for each RASS/BSC source, the probability Pid that the NIR source and X-ray source are uniquelyassociated, and the probability P no-id that none of the2MASS/PSC sources are associated with the X-ray source. The catalogincludes 3853 high quality (P id>0.98) X-ray-NIR matches,2280 medium quality (0.98 >= P id>0.9) matches, and4153 low quality (0.9 >= P id>0.5) matches. Of the highquality matches, 1418 are associations that are not listed in the SIMBADdatabase, and for which no high quality match with a USNO-A2 opticalsource was presented for the RASS/BSC source in previous work. Thepresent work offers a significant number of new associations withRASS/BSC objects that will require optical/NIR spectroscopy forclassification. For example, of the 6133 P id>0.92MASS/PSC counterparts presented in the association catalog, 2411 haveno classification listed in the SIMBAD database. These 2MASS/PSC sourceswill likely include scientifically useful examples of known sourceclasses of X-ray emitters (white dwarfs, coronally active stars, activegalactic nuclei), but may also contain previously unknown sourceclasses. It is determined that all coronally active stars in theRASS/BSC should have a counterpart in the 2MASS/PSC, and that the uniqueassociation of these RASS/BSC sources with their NIR counterparts thusis confusion limited.
| A catalogue of chromospherically active binary stars (third edition)
The catalogue of chromospherically active binaries (CABs) has beenrevised and updated. With 203 new identifications, the number of CABstars is increased to 409. The catalogue is available in electronicformat where each system has a number of lines (suborders) with a uniqueorder number. The columns contain data of limited numbers of selectedcross references, comments to explain peculiarities and the position ofthe binarity in case it belongs to a multiple system, classicalidentifications (RS Canum Venaticorum, BY Draconis), brightness andcolours, photometric and spectroscopic data, a description of emissionfeatures (CaII H and K, Hα, ultraviolet, infrared),X-ray luminosity, radio flux, physical quantities and orbitalinformation, where each basic entry is referenced so users can go to theoriginal sources.
| Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)
The LSPM catalog is a comprehensive list of 61,977 stars north of theJ2000 celestial equator that have proper motions larger than 0.15"yr-1 (local-background-stars frame). The catalog has beengenerated primarily as a result of our systematic search for high propermotion stars in the Digitized Sky Surveys using our SUPERBLINK software.At brighter magnitudes, the catalog incorporates stars and data from theTycho-2 Catalogue and also, to a lesser extent, from the All-SkyCompiled Catalogue of 2.5 million stars. The LSPM catalog considerablyexpands over the old Luyten (Luyten Half-Second [LHS] and New LuytenTwo-Tenths [NLTT]) catalogs, superseding them for northern declinations.Positions are given with an accuracy of <~100 mas at the 2000.0epoch, and absolute proper motions are given with an accuracy of ~8 masyr-1. Corrections to the local-background-stars propermotions have been calculated, and absolute proper motions in theextragalactic frame are given. Whenever available, we also give opticalBT and VT magnitudes (from Tycho-2, ASCC-2.5),photographic BJ, RF, and IN magnitudes(from USNO-B1 catalog), and infrared J, H, and Ks magnitudes(from 2MASS). We also provide an estimated V magnitude and V-J color fornearly all catalog entries, useful for initial classification of thestars. The catalog is estimated to be over 99% complete at high Galacticlatitudes (|b|>15deg) and over 90% complete at lowGalactic latitudes (|b|>15deg), down to a magnitudeV=19.0, and has a limiting magnitude V=21.0. All the northern starslisted in the LHS and NLTT catalogs have been reidentified, and theirpositions, proper motions, and magnitudes reevaluated. The catalog alsolists a large number of completely new objects, which promise to expandvery significantly the census of red dwarfs, subdwarfs, and white dwarfsin the vicinity of the Sun.Based on data mining of the Digitized Sky Surveys (DSSs), developed andoperated by the Catalogs and Surveys Branch of the Space TelescopeScience Institute (STScI), Baltimore.Developed with support from the National Science Foundation (NSF), aspart of the NASA/NSF NStars program.
| SB9: The ninth catalogue of spectroscopic binary orbits
The Ninth Catalogue of Spectroscopic Binary Orbits(http://sb9.astro.ulb.ac.be) continues the series of compilations ofspectroscopic orbits carried out over the past 35 years by Batten andcollaborators. As of 2004 May 1st, the new Catalogue holds orbits for2386 systems. Some essential differences between this catalogue and itspredecessors are outlined and three straightforward applications arepresented: (1) completeness assessment: period distribution of SB1s andSB2s; (2) shortest periods across the H-R diagram; (3)period-eccentricity relation.
| 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
| BVRI photometry of spectroscopic binaries
Not Available
| 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.
| The general catalogue of trigonometric [stellar] paralaxes
Not Available
| Spectroscopic binary orbits from photoelectric radial velocities. A synopsis of papers 1-100
Not Available
| CA II H and K measurements made at Mount Wilson Observatory, 1966-1983
Summaries are presented of the photoelectric measurements of stellar CaII H and K line intensity made at Mount Wilson Observatory during theyears 1966-1983. These results are derived from 65,263 individualobservations of 1296 stars. For each star, for each observing season,the maximum, minimum, mean, and variation of the instrumental H and Kindex 'S' are given, as well as a measurement of the accuracy ofobservation. A total of 3110 seasonal summaries are reported. Factorswhich affect the ability to detect stellar activity variations andaccurately measure their amplitudes, such as the accuracy of the H and Kmeasurements and scattered light contamination, are discussed. Relationsare given which facilitate intercomparison of 'S' values with residualintensities derived from ordinary spectrophotometry, and for convertingmeasurements to absolute fluxes.
| Kinematics of chromospherically active late-type dwarfs in the solar neighborhood
The space motions of chromospherically active late-type dwarfs(solar-type stars, K and M dwarfs, and BY Draconis binaries) areillustrated and discussed. Except for a small number of deviant stars,all the active single stars have the kinematics of young stars (ageabout 0.5 Gyr). The most egregious exception is HD 152391, which appearsto be a single star with a high level of chromospheric activity but withthe kinematics of the old disk population, for reasons unknown. The BYDra binaries, with a few exceptions, also have the kinematics of youth,being characterized by an age of about 1-2 Gyr. This lack of old BY Drabinaries seems puzzling, since a binary should be able to draw onorbital angular momentum to maintain rapid rotation well into old age,but this dearth is suggested to be due to the very rapid loss of angularmomentum that a double star can maintain until essentially all theangular momentum is lost and the stars coalesce. No strong kinematiccoherence is seen among the active single stars, indicating that thesestars were born in many different nurseries and have come to the solarneighborhood through random processes.
| Space motions of low-mass stars.
Radial-velocity measures are presented for 225 stars, most of which aredwarf K and M stars. The data were obtained with the CfA digitalspeedometer, whose uncertainty is less than 1 km/s. Calibrations ofthree earlier radial-velocity studies and comparisons with three othercontemporary ones lead to the evaluation of the standard error for anindividual star as determined in each investigation. The data from twomasks, matching solar type and M type stars, form a ratio that measuresstellar surface temperature quite closely and appear to be useful indetecting the presence of unseen companions. A few previouslyunrecognized binaries have been detected; those with most certaintyinclude stars nos. 366B, 453, and 46A of the McCormick lists of dwarfstars.
| Spectroscopic binary orbits from photoelectric radial velocities. Paper 75: BD +28 413
Not Available
| A survey of chromospheric emission and rotation among solar-type stars in the solar neighborhood
A spectroscopic survey of Ca II and H and K emission among late-typedwarfs is analyzed in order to identify solar neighborhood stars with(B-V) greater than 0.50 and less than 1.00. The observations were usedto calculate RHK, the fraction of the bolometric luminosityof a star which appears as HK emission. The angular velocities of thestars relative to the sun (Omega/Omega solar radius) were calculatedbased on a calibration of RHK with the Rossby number. Therelationship between age and the rotational properties of the stars wasalso analyzed in detail. It is shown that for stars of a givenRHK, age RHK increases slightly with increasing(B-V). The activity-age relation (RHK varies as exp -1/2) wasfound to be independent of mass for the late-type dwarfs. Therotation-age relation was also independent of mass, and the rotationrate of the sun was found to be normal for a star of its mass and age.It is suggested that the age dependencies of chromospheric activity arealso unrelated to mass and angular momentum loss may be considered aself-regulating mechanism which is not related to the details of stellarstructure such as the convective zone depth.
| Magnetic structure in cool stars. VII - Absolute surface flux in CA II H and K line cores
Middlekoop's (1982) conversion of the relative Ca II H and K line-coreintensity index determined with the Ca II H and K photometer at Mt.Wilson is revised into the line-core flux per unit area at the stellarsurface. The conversion factor is now established for stars ranging inluminosity class from V to II-III and in color from B - V = 0.3 to B - V= 1.6. A calibration of the stellar surface-flux units is derived bymeans of the solar flux spectrum. These results are compared with otherabsolute flux determinations, and the influence of the pass band on thedetected Ca II line-core flux is investigated. The Ca II line-coresurface flux exhibits a color-dependent minimum which differs betweenmain-sequence stars and giants. There is no conspicuous dependence ofthe minimal Ca II H and K flux on metallicity.
| 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.
| Catalogue of stars with CaII H and K emissions
Not Available
| The motions of K and M dwarf stars of different ages
Parallax and proper-motion results are summarized for 145 nearby K and Mdwarfs, and space motions are calculated for most of the sample, whichis not biased toward stars with high velocity. The space motions andtheir U, V, and W components are presented, the mean motion and velocitydispersion of the stars are derived, and the velocity distributions arecompared with previous results. The stars are divided into groupsrepresenting the young-disk, old-disk, and halo populations, and thesizes of the groups are examined along with their kinematicalproperties. The weights of the space motions of the individual starscomprising each group are evaluated by means of a rigorous method basedon the premise that the error in tangential velocity must necessarily bea distance-dependent parameter whereas that in radial velocity is not.The results obtained indicate an outward motion of the young stars withrespect to the old ones and confirm that the kinematical local standardof rest is age-sensitive.
| The luminosity law for late-type main-sequence stars in the solar neighborhood
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86..697E&db_key=AST
| Parallaxes and proper motions. IV.,V. .
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971AJ.....76...77K&db_key=AST
| Calcium emission intensities as indicators of stellar age.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970MNRAS.148..463W&db_key=AST
| Radial velocities of dK and dM stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1967AJ.....72..905W&db_key=AST
| Photoelectric observations of red dwarf stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956AJ.....61..213M&db_key=AST
| Dwarf M stars found spectrophotometrically .
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956AJ.....61..201V&db_key=AST
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| קבוצת-כוכבים: | משולש |
| התרוממות ימנית: | 02h25m40.18s |
| סירוב: | +28°45'58.1" |
| גודל גלוי: | 9.053 |
| מרחק: | 35.587 פארסק |
| תנועה נכונה: | 167.3 |
| תנועה נכונה: | -97.2 |
| B-T magnitude: | 10.261 |
| V-T magnitude: | 9.153 |
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