Speckle Interferometry at the US Naval Observatory. XIII.
The results of 1424 speckle interferometric observations of doublestars, made with the 26 inch (66 cm) refractor of the US NavalObservatory, are presented. Each speckle interferometric observation ofa system represents a combination of over 2000 short-exposure images.These observations are averaged into 1053 mean relative positions andrange in separation from 0.36″ to 61.92″, with a medianseparation of 10.31″. This is the 13th in a series of paperspresenting measurements obtained with this system and covers the period2006 January 12-December 29. Included in these data are nine oldermeasurements whose positions were previously deemed possibly aberrantbut are no longer classified this way following a confirmingobservation. This paper also includes the first data obtained using anew "secondary" camera, designed and built at USNO.
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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
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Photometry of F-K type bright giants and supergiants. 3: The luminosity, reddening, and heavy element abundance of GK stars
The reddening, luminosity, and heavy element abundance of 250 brightgiants and supergiants of type GK are discussed on the basis of 4 color,DDO, RI, and Geneva photometry Bright giants of type GK with age greaterthan 5 x 108 yr, and of type G0/3 with age greater than 2 x108 yr, are very scarce in the solar neighborhood. The medianspace motion vectors of the bright giants and supergiants with welldetermined space motions are (U, V, W) = (+10.6, -13.2, -7.7) +/- (12.3,8.8, 8.8) km/s. The M1 index for 4 color photometry, whencorrected for luminosity (gravity) effects, is sensitive to heavyelement abundance of the GK stars but may not be reliable for those oftype G0/3. The available spectroscopic determinations of (Fe/H) givemixed results with the two largest samples being internally consistentbut with a large zero-point difference. There is a similar zero-pointshift in the peak frequency of the photometrically determined values ofP(Fe/H) for the F type and for the GK type stars. There is littleevidence for an appreciable galactic, radial gradient in the P(Fe/H)values. A previously noted correlation of the heavy element abundanceindex, delta M1, with the amplitude defect in the B lightcurves of Cepheids, FB, and interpretation of the(PLFB) relation as a (PL(Fe/H)) relation needs furtherinvestigation in light of the apparent sensitivity of M1 toFe/H for the F stars (the domain of the Cepheids with P less than 10 d)and lack of this sensitivity for the G0/3 star (domain of the Cepheidswith P greater than 10 d).
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Photometry of F-K type bright giants and supergiants. I - Intermediate band and H-Beta observations
Over 1500 observations of 560 bright giants and supergiants of types F-Kare presented and compared to the observations by Gray and Olsen (1991).The present results include intermediate-band which is slightlydifferent from the Stromgren data by Gray and Olsen due to a differentwidth for the v filter. A systematic difference in m(1) - M(1) withdecreasing temperature is noted in the two H-Beta data sets, and thecorrelations are defined.
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Maximum separations among cataloged binaries
The paper classifies many of the widest common-motion binaries listed inthe Aitken catalog and list 72 physical pairs with known photoelectricphotometry, 31 physical pairs without good photometry, and 27 opticalpairs. As a function of primary types, the physical systems have upperlimits to their separations that are exceeded by some of the opticalpairs. The fact that optical pairs occur with larger separations impliesthat the limits are real ones and not just catalog limitations. Thoselimits (in AU) are expressed by 2500 M1 exp 1.54 for B5-KO main-sequenceprimaries. The same limits hold for the Trapezium and hierarchicalsystems studied previously.
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A study of the nine interstellar dark clouds
An investigation of the physical and chemical properties of nineinterstellar dark clouds, L1407, L1551, L1544, L134N, L63, L1147, L1235,L1253, and L1257 are reported. Observations of a variety of atomic andmolecular species have been obtained, and the clouds have been partiallymapped in the near infrared. The observations have been compared withtheoretical models of the line emission and absorption from interstellarclouds to derive many of the fundamental physical parameters. Thetemperatures, densities, masses, sizes, and abundances of atomic andmolecular species in the clouds have been determined along withvariations of the density and temperature as a function of radius.
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Catalogue of stars with CaII H and K emissions
Not Available
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Masses of red giants. I - Mean initial mass from visual binary data
Existing information on red-giant masses is reviewed, and an independentmethod for determining the frequency distribution of initial masses ofred giants is presented which is based on analysis of visual binarysystems containing a red giant and a main-sequence star (RG-MS systems).A list of RG-MS systems is compiled which yields an apparent frequencydistribution of the spectral types of the secondaries. This apparentdistribution is transformed to a 'true' distribution of secondary massesby accounting for certain selection effects; the true distribution isthen transformed into a distribution of initial primary masses (i.e.,initial masses of red-giant components) by assuming a form for thedistribution of mass ratios. Values in the range from 0.8 to 1.2 solarmasses and an upper limit of 1.4 solar masses are determined for themean initial masses of red giants and shown to be in satisfactoryagreement with the theoretical prediction of about 1 solar mass.
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Cyanogen strengths, mixing and supermetallicity in G and K giants
Wide visual binaries consisting of a G or K giant in physicalassociation with an F dwarf, observed using DDO and ubvy photometry,were used to study the possibility of mixing in the giants prior to orduring helium core burning. The two abundance indices, delta m1 of theuvby system, and delta CN of the DDO system, are compared to study thepossibility that mixing from a hydrogen burning region has affected theCN strengths of the giants.
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Absolute magnitudes of stars from widths of chromospheric CaII emission lines.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJ...205..823W&db_key=AST
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Radial velocity measurements of visual binaries. 1.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974AJ.....79..866B&db_key=AST
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Observational studies relating to stars formation. III.
Not Available
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An investigation of the consistency of the calibrations of the UVBY beta and GNKMF photometric systems.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971A&A....15..161O&db_key=AST
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Determination of atmospheric parameters for G and K giants by means of photoelectric indices.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971A&A....15..123H&db_key=AST
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UBV observations of visual double stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971PASP...83..488L&db_key=AST
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UBV photometry of 550 F, G and K type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966MNRAS.133..475A&db_key=AST
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A UBV Study of 94 Wide Visual Binaries.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1964ApJ...139.1105T&db_key=AST
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Micrometer Measures of Double Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961ApJS....6....1K&db_key=AST
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Spectral Classification of Visual Binaries Having Primaries Above the Main Sequence
Not Available
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INHABITED SKY
