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Photoelectric observations of CPM stars in the BVRI system
A photometric program to estimate the frequency of close unresolvedcompanions in visual binary systems has been developed. The sensitivityof the detection depends on the accuracy of the differential photometricmeasurements of binary components. Unresolved companions up to sevenmagnitudes fainter than the primary are detectable in the BVRIphotometric systems.
| Common proper motion stars in the AGK 3
A search was made of common-proper-motion (CPM) systems among AGK 3stars. The selection of physical systems was based upon the ratiobetween the angular separation (rho) and the proper motion (mu); the CPMstars found are presented in two tables. Table I lists systems withrho/mu less than 1000 years. It contains 326 entries, and the proportionof optical pairs is estimated to be 1 percent. Table II lists systemswith rho/mu in the range 1000 to 3500 years; it contains 113 systems,but only 60 percent of them are physical. Nevertheless, these systemsoften have separations larger than 10,000 AU and are the mostinteresting for the study of the tail of the distribution function ofthe semimajor axes.
| A sample of solar-type stars of known age
A sample of field F and G dwarfs of known ages is presented. All thedwarfs are secondaries of visual binaries in which the temperature andgravity of the hotter primary has been estimated from Stromgrenphotometry, and its age derived from reference to isochrones. This ageis taken to apply to the secondary. Even in the case of F-typesecondaries, which themselves have measured Stromgren indices, it ismuch better to estimate ages from the primaries as it is demonstratedthat use of isochrones to determine age of stars not far evolved fromthe main sequence can lead to significant systematic overestimates ofages when the photometric measurements have typical random errors. Anumber of systems in which photometry is available for both componentshave primaries which appear much younger than the secondaries,suggesting a need for further investigation.
| Ages and uvbybeta photometry of wide visual binaries. II
Visual magnitudes and color indices b-y, m1, c1 and beta have beenobtained for the members of 39 double or multiple systems containingstars with magnitudes greater than 4m. Relationships between stellarages, spectral types and photometric indices are given from a sample ofabout 3,500 stars. Data is presented with regard to MK spectral types,the separation, and absolute magnitudes; also tabulated are the meanvalues of photometric unreddened indices with their standard deviationfor intervals of 0.2 in log age. From calculations for each binary ofthe relative difference in the ages of the components and the differencein the effective temperatures, an increase in the relative differencesin ages with the differences in temperatures is noted.
| UVBY beta study of A-and F-type visual binaries. I.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976AJ.....81..107M&db_key=AST
| A list of stars with common proper motions.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958AJ.....63..246V&db_key=AST
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Gözlemler ve gökölçümü verileri
| Takýmyýldýz: | Baliklar |
| Sað Açýklýk: | 01h41m19.01s |
| Yükselim: | +10°06'49.5" |
| Görünürdeki Parlaklýk: | 8.811 |
| özdevim Sað Açýklýk: | 163.5 |
| özdevim Yükselim: | 34.6 |
| B-T magnitude: | 9.488 |
| V-T magnitude: | 8.867 |
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