As part of a thorough study of the luminosity function of Sco-Cen, UBV, and H_{beta}_ photometry has been acquired for a large number of mid B- to late A-type stars which are within or surrounding the Scorpius-Centaurus OB association. UBV and H_{beta}_ photoelectric measures have been obtained for all the B stars without previous observations and for many of those with in the large field 280deg<=l<=362deg, +10deg<=b<=+40deg, and m-M<=7.5mag. Within the upper Scopius subgroup (ScoOB2), 341deg<=l<=362deg, +10=<b=<30deg, UBV and H_{beta}_ photometry was obtained for all B stars listed in the MSC(HD) catalog. As well, UBV measures were obtained for all the A-type stars within this field.
Photoelectric and spectroscopic observations of the protoplanetary object V1853 Cyg, a B supergiant with an IR excess, are given. The observations were carried out with a UBV photometer attached to the 60-cm Zeiss telescope at the Crimean Station of the Stenberg Astronomical Institute.
We present a proper-motion, CCD photometric study of stars in the distant halo globular cluster Palomar 13. The absolute proper motion of Pal 13 with respect to the background galaxies, derived from moderate-scale photographic plates separated by a 40 year baseline, is (pmRAcosDE, pmDE)=(2.30, 0.27)+/-(0.26, 0.25)mas/yr.
From observations at the European Southern Observatory, spectrographic and photometric data are presented for 91 supergiant stars belonging to the Small Magellanic Cloud and its Wing. The data include MK classes for 52 stars, radial velocity data for 51 stars and UBV photometry for 90 stars. In V the limiting magnitude for the spectrographic observations is 13.7 and for the photometric observations 13.9. Whenever possible, radial velocities for interstellar CaII and [OII] have been measured and listed. In Remarks to the Catalogue notes are given for the individual stars concerning the obtained data and comparisons with results of previous investigations.
Our goals were to analyse 52 photographic and 651 electronic spectra of beta Lyr to obtain additional information about circumstellar matter and to investigate spectrophotometric information for the first time.
New, accurate radial velocities and photoelectric UBV photometry of 83 red-giant candidates in the field of the rich, intermediate-age open cluster NGC 2477 ([Fe/H]=-0.05, age ~1Gyr) are presented and discussed. From 49 constant-velocity members we find a mean cluster velocity of +7.32+/-0.13km/s and confirm the membership of 76 of the stars. Among the cluster members, we identify 26 definite and 1 probable spectroscopic binaries and determine orbits for 13 of these systems, with periods ranging from 40 to 4578 days. The binary frequency is thus rather high (27/76=36%). The observed internal radial velocity dispersion of the cluster, as determined from the single member stars, is 0.93km/s, corrected for the small average observational error of 0.22km/s. Fitting King-type models to the observed stellar density distribution and velocity dispersion, and assuming a distance of 1.25kpc, we find the core and tidal radii of NGC 2477 to be 1.8 and 8.1pc, respectively, and estimate that the mass of cluster stars down to V=17, corresponding to ~1M_{sun}_, is at least 5400 M_{sun}_. The substantial differential reddening of NGC 247 requires a more detailed study before definitive isochrone fits can be made.
The A-type star HR 6412 = V2368 Oph was used by several investigators as a photometric comparison star for the known eclipsing binary U Oph but was found to be variable by three independent groups, including us. By analysing series of new spectral and photometric observations and a critical compilation of available radial velocities, we were able to find the correct period of light and radial-velocity variations and demonstrate that the object is an eclipsing and double-lined spectroscopic binary moving in a highly eccentric orbit. We derived a linear ephemeris Tmin.I=HJD(2454294.67+/-0.01)+(38.32712+/-0.00004)d*E and estimated preliminary basic physical properties of the binary.
UBV and uvby-beta observations of Orion OB1 Association
Short Name:
II/36
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Catalogue of Individual UBV and uvby-beta Observations of Stars in the Region of the Orion OB 1 Association presents individual UBV observations of 106 stars in the vicinity of the Orion Nebula (the Sword region) and individual uvby-beta observations of 508 stars in all regions of the Orion OB 1 association. For the UBV data the stars are identified by their Brun (1935) numbers, with cross identifications to the chart numbers used in Warren and Hesser (1977); the uvby-beta stars are identified by the aforementioned chart numbers and HD, BD or P (Parenago 1954) numbers in that order of preference. The catalogue contains the data of all observations and is intended to provide data for investigations of variability in the Orion region. See <http://obswww.unige.ch/gcpd/ph01.html> for a full description of the UBV system, and <http://obswww.unige.ch/gcpd/ph04.html> for a description of uvby-beta system.
130 stars in the region of the Zeta Sculptoris cluster have been observed photoelectrically, most of them in UBVBeta and about half of them in uvby and a few also in the Cousins' system.
