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HD 172052


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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available

A catalog of rotational and radial velocities for evolved stars. II. Ib supergiant stars
Rotational velocity vsin i and mean radial velocity are presented for asample of 231 Ib supergiant stars covering the spectral region F, G andK. This work is the second part of the large survey carried out with theCORAVEL spectrometer to establish the behavior of the rotation for starsevolving off the main sequence (De Medeiros & Mayor 1999). Thesedata will add constraints to the study of the rotational behavior inevolved stars, as well as solid information concerning tidalinteractions in binary systems and on the link between rotation,chemical abundance and activity in stars of intermediate masses. Basedon observations collected at the Haute-Provence Observatory,Saint-Michel, France and at the European Southern Observatory, La Silla,Chile Table 1 is 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/395/97

Colour excesses of F-G supergiants and Cepheids from Geneva photometry.
A reddening scale for F-G supergiants and Cepheids is presented.Supergiants with low reddenings or in clusters form the basis of thecalibration. In this sense, it is entirely empirical. The data have beenobtained in the Geneva photometric system. Comparisons with otherreddening scales show no disagreement. The only problem is with Fernie'sscale for Cepheids (1990), where a systematic trend exists. Its originis not clear. It is suggested to extend the number of supergiants withindependently obtained colour excesses in order to test the existence ofa possible luminosity dependence of the calibration. A period-colourrelation for Cepheids is deduced, on the basis of the present reddeningcorrections. It gives strong support for V473 Lyr being a secondovertone pulsator.

Colour excesses and absolute magnitudes for non-Cepheid F-G supergiants from uvbybeta photometry
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990A&A...239..205A&db_key=AST

Ultraviolet survey for hot companions among nonvariable yellow supergiants
Twenty nonvariable yellow supergiants have been observed for the firsttime with the International Ultraviolet Explorer satellite, with the aimof discovering hot companions. Two newly discovered systems areannounced: HD 74395 (G2 I + B9.5 IV-V) and HD 193469 (later than G0 + B8IV-V). The Cepheid HD 9250 was also observed, but no hot companion wasfound. Some stars independently known to have a hot companion wereincluded in order to study the properties of the companions and tocompare with previous work. Atmospheric models were used to fit theoverall energy distribution of the binary system, allowing an estimateof Te, log g, and the spectral type of the companion. The magnitudedifferences, in the V band, between the yellow supergiants and theircompanions were calculated. The possibility of using this magnitudedifference and the spectral type determined for the hot companions toestimate M(v) for the yellow supergiants and the distance to the systemsis explored. Comparison of the binaries' positions in the H-R diagramwith theoretical evolutionary tracks suggests that the masses of theprimaries are contained between 5 and 9 solar masses and that, onaverage, they are about twice as massive as their hot companions.

A photometric determination of the metal content for F-G type supergiants in the Large Magellanic Cloud
A VBLUW photometric analysis is used to derive the metal content of some100 F- and G type supergiants in the LMC. Using the empirical locus ofPel in the V-B/B-L diagram in conjunction with the relative dependenceof theoretical colors on the metal abundance, a metal deficiency of1.4-1.6 is found for the LMC stars in comparison with those in the solarneighborhood. With an average UBV system foreground reddening of E(B-V)= 0.05 for the LMC, these stars have a metal content of 0.66 + 0.11,-0.03 of the solar abundance. Agreement is found with the result ofprevious studies. Application to the derivation of the reddenings ofmost of the galactic supergiants is noted.

Nineteen new spectroscopic binaries and the rate of binary stars among F-M supergiants
Nineteen spectroscopic binaries (SBs) have been discovered in radialvelocity measurements made with the CORAVEL spectrophotometer on 181northern F-M supergiants. The rate of detected SBs among northern F-Msupergiants is 21 percent, without any dependence on spectral orluminosity class. The study of the binary F-M supergiants with knownorbital elements indicates that all the systems with a period smallerthan the critical value P(circ) have a nearly circular orbit. The valueof P(circ) depends on the luminosity class, being 400-600 d for class Iband 2000-7000 d for class Ia. This circularization of the orbits may bedue to the transfer of angular momentum during the phase of binary massexchange.

New UBVRI photometry for 900 supergiants
A description is presented of the results obtained in connection with asystematic program of supergiant photometry on the Johnson UBVRI system.During the eight years after the start of the program, almost 1000 starshave been observed, about 400 three or more times each. The originalselection of stars used the spectral type catalog of Jaschek et al.(1964) to choose supergiants. Since observations were possible from bothChile and Canada, no declination limits were imposed, and no particularselection criteria were imposed other than to eliminate carbon stars.These are so red as to require enormous extrapolations of thetransformation equations.

Estimation of spectral classifications for bright southern stars with interesting Stromgren indices
This paper investigates the degree of success with which uvby photometrycan be applied to predict spectral classifications for 947 A, F, and Gstars brighter than an apparent magnitude of 8.3 and with four-colorindices indicating some kind of interesting, unusual, or peculiarspectrum. One or several possible spectral classifications are estimatedfor each star from photometry alone, double stars are distinguished, andthe estimates are compared with published classifications. The resultsshow that the framework provided by uvby photometry can be extended toinclude most G and K stars, reddened stars, peculiar stars, and certaintypes of double star.

Further photometry of Cepheid-like supergiants
Photoelectric photometry in Johnson's UBVRI system has been carried outfor 19 supergiants having spectral classifications similar to classicalCepheids. This is part of a continuing search to find either previouslyundiscovered low-amplitude Cepheids or stable stars within the Cepheidinstability strip on the H-R diagram. Of the present stars, only one, HD101947, has been found to show significant variability.

Five-channel photometry of cepheids and supergiants in the southern Milky Way.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...24..413P&db_key=AST

The Atmospheres of the F-Type Supergiants II. The Line and Continuous Spectra
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972ApJS...24..255O&db_key=AST

Photometric data for 139 supergiants.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972AJ.....77..150F&db_key=AST

Color Excesses for Supergiants and Classical Cepheids.VI. on the Intrinsic Colors and the Hess Diagram of Late-Type Supergiants.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961ApJ...134..850K&db_key=AST

Color Excesses from Six-Color Photometry of Supergiant Stars
Not Available

Line Broadening in High-Luminosity Stars. II. Less Luminous Supergiants.
Abstract image available at:http://adsabs.harvard.edu/abs/1958ApJ...127..658A

Spectral Classification of Stars Listed in Miss Payne's Catalogue of C Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1951ApJ...113..304B&db_key=AST

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Сазвежђа:Стрелац
Ректацензија:18h39m02.07s
Deклинација:-23°10'55.5"
Apparent магнитуда:6.729
Даљина:1369.863 parsecs
Proper motion RA:-1.1
Proper motion Dec:-5.3
B-T magnitude:7.498
V-T magnitude:6.793

Каталог и designations:
Proper имена   (Edit)
HD 1989HD 172052
TYCHO-2 2000TYC 6858-1190-1
USNO-A2.0USNO-A2 0600-36122957
HIPHIP 91446

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