The DDO IVC Distance Project: Survey Description and the Distance to G139.6+47.6
We present a detailed analysis of the distance determination for oneintermediate-velocity cloud (IVC, G139.6+47.6) from the ongoing DDO IVCDistance Project. Stars along the line of sight to G139.6+47.6 areexamined for the presence of sodium absorption attributable to thecloud, and the distance bracket is established by astrometric andspectroscopic parallax measurements of demonstrated foreground andbackground stars. We detail our strategy regarding target selection,observational setup, and analysis of the data, including a discussion ofwavelength calibration and sky subtraction uncertainties. We find adistance estimate of 129+/-10 pc for the lower limit and257+211-33 pc for the upper limit. Given the highnumber of stars showing absorption due to this IVC, we also discuss thesmall-scale covering factor of the cloud and the likely significance ofnondetections for subsequent observations of this and other similarIVCs. Distance measurements of the remaining targets in the DDO IVCproject will be detailed in a companion paper.
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Photometry from the HIPPARCOS Catalogue: Constant MCP Stars, Comparison and Check Stars
Photometry from the Hipparcos catalogue is used to verify the constancyof four magnetic CP stars, as well as the comparison and the check starsused for variability studies of normal and chemically peculiar B and Astars with the Four College Automated Photoelectric Telescope;variability in these stars can produce spurious results. A few of thecomparison stars are found to be variable and should be replaced forfuture differential photometric studies.
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On the possible variability of metallic-line and Mercury-Manganese stars
Differential Stromgren uvby photometric observations from the 0.75-mFour College Automated Photoelectric Telescope were obtained for threemetallic-line and three Mercury-Manganese stars. None were found to bevariable. These sharp-lined stars may not be the best tests for classvariability as their polar axes are pointed towards the earth. Eachpresents essentially the same visible hemisphere as it rotates. Tables2-7 are available in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
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Differential UBV Photometry of the CP3 Star HD 89822
Not Available
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UVBY photometry of the suspected variable stars 53 Tauri, 68 Tauri, HR 4072, and HR 6096
Stromgren uvby photometry of four suspected variable stars is presented.Observations made at the Four College Automated Photoelectric Telescopeshow that the two mercury-manganese stars 53 Tauri and HR 4072 and themetallic lined star 68 Tauri are non-variable on time scales of a fewdays to within the accuracy of the observations. HR 6096, which has beenclassified as a mild silicon star, is not found to be variable and maybe a metal-rich normal B star.
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Photoelectric photometry of chemically peculiar stars at the Catania Astrophysical Observatory. II - Observations of the CP3 stars HD 3322, HD 27295 and HD 89822
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1991A&A...244..327C&db_key=AST
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ICCD speckle observations of binary stars. IV - Measurements during 1986-1988 from the Kitt Peak 4 M telescope
One thousand five hundred and fifty measurements of 1006 binary starsystems observed mostly during 1986 through mid-1988 by means of speckleinterferometry with the KPNO 4-m telescope are presented. Twenty-onesystems are directly resolved for the first time, including newcomponents to the cool supergiant Alpha Her A and the Pleiades shellstar Pleione. A continuing survey of The Bright Star Catalogue yieldedeight new binaries from 293 bright stars observed. Corrections tospeckle measures from the GSU/CHARA ICCD speckle camera previouslypublished are presented and discussed.
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Photoelectric Observations of HR 4047
Not Available
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The local system of early type stars - Spatial extent and kinematics
Published uvby and H-beta photometric data and proper motions arecompiled and analyzed to characterize the structure and kinematics ofthe bright early-type O-A0 stars in the solar vicinity, with a focus onthe Gould belt. The selection and calibration techniques are explained,and the data are presented in extensive tables and graphs and discussedin detail. The Gould belt stars of age less than 20 Myr are shown togive belt inclination 19 deg to the Galactic plane and node-lineorientation in the direction of Galactic rotation, while the symmetricaldistribution about the Galactic plane and kinematic properties (purecircular differential rotation) of the belt stars over 60 Myr oldresemble those of fainter nonbelt stars of all ages. The unresolveddiscrepancy between the expansion observed in the youngest nearby starsand the predictions of simple models of expansion from a point isattributed to the inhomogeneous distribution of interstellar matter.
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Four-colour photometry of B stars north of B = + 45 deg and comparison with the south
Four-color photometry of 33 Henry Draper B stars north of b = + 45 degis presented. Most are little-reddened B or intermediate-A stars. A newAm star is discovered. The new measures essentially complete uvbyphotometry of all HD B stars within 45 deg of either galactic pole. Thenorthern and southern cones of HD B stars are compared, and selectioneffects deduced. Far from the galactic plane, it appears that B starsmay be equally distributed north and south of the plane; closer to thesun, an asymmetry associated with Gould's Belt is evident.
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Photometric UBV period study of eight AP stars
Eight Ap stars for which periods had been determined by Winzer (1974)were the subject of an independent period determination. All were starswhich were found to be short-period variables and which showed thetypical small-amplitude variation associated with short periods. For sixof these, the period was confirmed. For one, HR 9017, a different andbetter period was determined and for the remaining star, HR 4430,periodic variation was not observed.
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Pulsation in peculiar A stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975AJ.....80..698P&db_key=AST
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Rotational Velocities of a0 Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJS...28..101D&db_key=AST
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Four-color and H beta photometry for the bright B8 and B9 type stars north of declination -10 degre.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973AJ.....78..738C&db_key=AST
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U, b, v, and Hβ Photometry for the Bright B8- and B9-TYPE Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963ApJ...137..530C&db_key=AST
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INHABITED SKY
