We present wide-area UBRI photometry for globular clusters around the Leo group galaxy NGC 3379. Globular cluster candidates are selected from their B-band magnitudes and their (U-B)_0_ versus (B-I)_0_ colours. A colour-colour selection region was defined from photometry of the Milky Way and M31 globular cluster systems. We detect 133 globular cluster candidates, which supports previous claims of a low specific frequency for NGC 3379.
We present UBRI photometry and spectra for 60 quasars found within 1{deg}^2^ centered on the J0053+1234 region, which has been the subject of the Caltech Faint Galaxy Redshift Survey. Candidate quasars were selected by their ultraviolet excess with respect to the stellar locus and confirmed spectroscopically. The quasars span a wide range in brightness (17.5<B<21.6) and redshift (0.43<z<2.38).
We describe a new estimate of the radio galaxy 1.4 GHz luminosity function and its evolution at intermediate redshifts (z~0.4). Photometric redshifts and color selection have been used to select B_J_<23.5 early-type galaxies from the Panoramic Deep Fields, a multicolor survey of two 25deg^2^ fields. Approximately 230 radio galaxies have then been selected by matching early-type galaxies with NVSS radio sources brighter than 5mJy. Estimates of the 1.4GHz luminosity function of radio galaxies measure significant evolution over the observed redshift range. For an {Omega}_M_=1 cosmology the evolution of the radio power is consistent with luminosity evolution where P(z)~P(0)(1+z)^K_L_^ and 3<K_L_<5. The observed evolution is similar to that observed for UVX and X-ray selected active galactic nuclei and is consistent with the same physical process being responsible for the optical and radio luminosity evolution of active galactic nuclei.
Results of photoelectric UBVRI photometry of 78 stars and photographic PDS and CCD photometry for 437 stars are presented for Collinder 110, an old open cluster at low Galactic latitude. Proper motions obtained from Lick Sky Survey plates were used to identify 39 stars as foreground objects. The cluster's reddening, distance, and age are estimated as E(B-V)=0.50+/-0.03mag, r=1950+/-300pc, and t=1.4+/-0.3Gyr, assuming a solar metal abundance.
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.
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.
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.
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.
UBV CCD absolute photometry and differential astrometry of 111 southern visual binaries are presented. Observations have been performed at Las Campanas Observatory (Chile) in 1991-92 at 61-cm telescope. The separation range is 2.5-8arcsec. The mean epoch of the measurements is 1992.0. The photometry (table 1) was calibrated by one night of standard star observations. The positional parameters (table 3) are given in the reference system J2000 and calibrated using Hipparcos and CDS data. An additional table 2 provides the notes on observational circumstances.
