UBV (RI)c observations of Johnson's standard sequence in IC 4665.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996MNRAS.282..313M&db_key=AST
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UBV(RI)c photometry of equatorial standard stars - A direct comparison between the northern and southern systems
UBV(RI)c photometry of 212 stars from Landolt's list of equatorialstandards is presented. The observations are tied to the system definedby Cousin's E-region standards. A comparison of the present results withLandolt's reveals reasonably good agreement for (V-R)c and (V-I)c, butmarked systematic differences for (B-V) and (U-B). The UBV systems ofCousins and Landolt are evidently not the same and both probably differfrom Johnson's original system.
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First detection of the astrometric orbit of the single-lined spectroscopic binary epsilon Librae
The Multichannel Astrometric Photometer of the University ofPittsburgh's Allegheny Observatory was used to successfully measure forthe first time the astrometric orbit of the single-lined spectroscopicbinary epsilon Lib. Solution of the orbit indicates that the secondarycomponent is a 0.5-solar-mass star, assuming that the F5 IV primary is1.3 solar mass. If the secondary is on the main sequence, then it islater than a K5 star, but earlier than an M2 star. In addition todetection of the astrometric orbit of epsilon Lib, two references starsused in the observations, AO 754 and AO 755, are found to be acommon-proper-motion pair.
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Photoelectric observations of classical cepheids.
Not Available
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UBVRI photometric standard stars around the celestial equator
It is pointed out that accurate, internally consistent, and readilyaccessible standard star photometric sequences are necessary for thecalibration of the intensity and color data which astronomers obtain atthe telescope. The photometric results provided in connection with thepresent study represent the first part of an effort which is concernedwith the presentation of UBVRI photoelectric photometric standard starsin the magnitude range from 7 to 17 over as broad a range in color aspossible. All of the photometric observations were made with a 31034type photomultiplier used in a pulse counting mode. Some 15 to 25standard stars chosen from Cousins' lists (1973, 1976) in the E-regionswere observed with an 0.4-m telescope each night along with the programstars. UBVRI standard stars were observed periodically throughout thenight. Observations with a 0.9-m telescope were also conducted. TheUBVRI photoelectric observations take into account 223 stars.
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Spectral classifications for Landolt's celestial equatorial standard stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1979AJ.....84..783D&db_key=AST
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Equatorial UBVRI photoelectric sequences
From 1335 BVRI observations of 189 stars in selected areas 92-115,Landolt's (1973) network of faint UBV standards has been extended to RI. Of these stars, 173 have four or more observations. The (U-B) valuesof Landolt are adopted, and a well-observed equatorial faint-starnetwork is presented on the Johnson UBVRI photometric system.
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