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Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS Radial velocities have been determined for a sample of 2930 B2-F5 stars,95% observed by the Hipparcos satellite in the north hemisphere and 80%without reliable radial velocity up to now. Observations were obtainedat the Observatoire de Haute Provence with a dispersion of 80Ä,mm(-1) with the aim of studying stellar and galactic dynamics.Radial velocities have been measured by correlation with templates ofthe same spectral class. The mean obtained precision is 3.0 km s(-1)with three observations. A new MK spectral classification is estimatedfor all stars. Based on observations made at the Haute ProvenceObservatory, France and on data from The Hipparcos Catalogue, ESA.Tables 4, 5 and 6 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr or viahttp://cdsweb.u-strasbg.fr/Abstract.htm
| UBVRI photometry of 225 AM stars UBVRI photometry of 225 Am stars taken from Mendoza's (1974) catalog ispresented. The results are compared with those obtained by Feinstein(1974) for 21 of the stars and with the values of Johnson et al. (1966).It is assumed that in the first approximation the (V-I) color index ofan unreddened Am star is equal to that of a normal main-sequence star; astandard main sequence is defined for A and early F stars, and thefive-color photometry is analyzed by means of plots of U-V vs. V-I, B-Vvs. V-I, and V-R vs. V-I. Mean color deficiencies of Am stars areexamined, and it is suggested that an unreddened star located below themain-sequence A0-F2 line in the (V-I, U-V) plane is a photometric Amstar. It is concluded that: (1) photometric Am stars have colordeficiencies (as a function of V-I) which, on the average, are 0.07 magin (U-V) color index and 0.025 mag in (B-V) color index; (2) Am starswith V-R less than 0.25 mag may also have a color deficiency of about0.01 mag; (3) Am stars with V-R greater than 0.3 mag may have a colorexcess of approximately 0.01 mag; and (4) Am stars with V-R between 0.25and 0.3 mag may have normal colors.
| Classification spectrale d'etoiles AP et Am. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975A&AS...21...25F&db_key=AST
| Multicolor photometry of metallic-line stars. III. A photometric catalogue Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974RMxAA...1..175M&db_key=AST
| UVBY photometry of AM and AP stars. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973AJ.....78..192W&db_key=AST
| New Peculiar Stars Noted on Objective-Prism Plates Not Available
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Посматрања и Астрометриски подаци
Сазвежђа: | Делфин |
Ректацензија: | 20h27m15.64s |
Deклинација: | +16°42'39.7" |
Apparent магнитуда: | 7.566 |
Даљина: | 216.92 parsecs |
Proper motion RA: | -12.1 |
Proper motion Dec: | -22.8 |
B-T magnitude: | 7.992 |
V-T magnitude: | 7.602 |
Каталог и designations:
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