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Evolved GK stars near the sun. I - The old disk population
A sample of nearly two thousand GK giants with intermediate band, (R,I),DDO and Geneva photometry has been assembled. Astrometric data is alsoavailable for most of the stars. The some 800 members of the old diskpopulation in the sample yield accurate luminosities (from two sources),reddening values and chemical abundances from calibrations of thephotometric parameters. Less than one percent of the objects arepeculiar in the sense that the flux distribution is abnormal. Thepeculiarity is signaled by strong CH (and Ba II) and weak CH. The CH+stars are all spectroscopic binaries, probably with white dwarfcompanions, whereas the CH- stars are not. A broad absorption band,centered near 3500 A, is found in the CH+ stars whereas the CH- objectshave a broad emission feature in the same region. The intensity of theseabsorptions and emissions are independent of the intensity of abnormalspectral features. Ten percent of the old disk sample have a heavyelement abundance from one and a half to three times the solar value.The distribution of the heavy element abundances is nearly a normal onewith a peak near solar abundance and ranges three times to one sixthsolar. The distribution of the (U, V) velocities is independent of theheavy element abundance and does not appear to be random. Ten percent ofthe old disk stars show a CN anomaly, equally divided between CN strongand CN weak. Several stars of individual astrometric or astrophysicalimportance are isolated.
| Search for wide binaries in the Yale Bright Star Catalogue
A specific scheme for identifying wide binary candidates in the YaleBright Star Catalogue is presented. The choice of criteria for selectingcandidates is discussed, and the final criteria are used to compile apreliminary list of candidates which is presented and discussed. Thestatistics of the candidate list are characterized, and the list is usedto compute upper bounds on the wide binary density using a simpletheoretical model.
| Narrow-band photometry of late-type stars. II
This paper presents extensive narrow-band photometry in the Uppsalasystem supplementing earlier published mesurements so that data now areavailable for all late-type stars brighter than V = 6.05 and a number ofgalactic cluster members. Numerous UBV and BV measurements are alsopublished. The data are used to determine relations for the predictionof UBV intrinsic colors for late-type stars from the narrow-bandmeasurements. The main purpose of the data is to constitute the basisfor the determination of solar-neighborhood space densities of late-typestars, mainly giants of different kinds; these space densities will becombined with narrow-band data for fainter stars in the north Galacticpole region to yield the decrease of space density with distance fromthe galactic plane for many kinds of late-type stars.
| Visual measurements of southern double stars
A double-star observing program is described which has been started atCordoba with a 30 cm refractor. Usually neglected Index Catalog ofVisual Double Stars (IDS) pairs south of -60 deg are selected forobservation, most of them having been measured only one or two timespreviously. A total of 174 micrometric observations of 78 wide pairs arepresented together with a few measurements of 9 double stars not foundin the IDS. Also reported is a list of 135 additional measurements of 26test stars. By comparison with all earlier observations, an estimate forthe personal equation has been made, which is applied in combinationwith catalogue proper motions to investigate the nature of many of thesepairs.
| Radial Velocities of Bright Southern Stars - Part Two - 53 Late-Type HR and FK4 Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983A&AS...52..479A&db_key=AST
| UVBY photometry of wide visual double stars with B, A and F spectral type- I.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978A&AS...34..453O&db_key=AST
| On the cause underlying the spectral differences of the stars.
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Besorolás csoportokba:
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Pozíciós és asztrometriai adatok
| Csillagkép: | Távcső |
| Rektaszcenzió: | 19h52m37.60s |
| Deklináció: | -54°58'16.0" |
| Vizuális fényesség: | 5.74 |
| Távolság: | 108.578 parszek |
| RA sajátmozgás: | 18.8 |
| Dec sajátmozgás: | 3 |
| B-T magnitude: | 6.809 |
| V-T magnitude: | 5.803 |
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