- ID:
- ivo://CDS.VizieR/J/A+A/487/1081
- Title:
- uvby photometry of 6 eclipsing binaries
- Short Name:
- J/A+A/487/1081
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate mass, radius, and abundance determinations from binaries provide important information on stellar evolution, fundamental to central fields in modern astrophysics and cosmology. Within the long-term Copenhagen Binary Project, we aim to obtain high-quality light curves and standard photometry for double-lined detached eclipsing binaries with late A, F, and G type main-sequence components, needed for the determination of accurate absolute dimensions and abundances, and for detailed comparisons with results from recent stellar evolutionary models. Between March 1985 and July 2007, we carried out photometric observations of AD Boo, HW CMa, SW CMa, V636 Cen, VZ Hya, and WZ Oph at the Stromgren Automatic Telescope at ESO, La Silla. We obtained complete uvby light curves, ephemerides, and standard uvby{beta} indices for all six systems.
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- ID:
- ivo://CDS.VizieR/J/A+A/402/509
- Title:
- uvby photometry of four MC eclipsing binaries
- Short Name:
- J/A+A/402/509
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new accurate CCD uvby light curves for the LMC eclipsing binaries HV 982 and HV 12578, and for the SMC systems HV 1433 and HV 11284 obtained at the Danish 1.5m telescope at ESO, La Silla, equipped with a direct camera and CCD #28 (a thinned 1024x1024 Tek device), during several periods between November 1992 and November 1995. The light curves were derived from DoPHOT photometry, and typical accuracies are between 0.007 and 0.012mag per point. Standard uvby indices have also been established for each binary, primarily for determination of interstellar reddening and absorption. For HV 982 and HV 12578, accurate photometric elements have been established. Both systems consist of two detached components of comparable sizes in an eccentric orbit.
- ID:
- ivo://CDS.VizieR/J/AJ/127/980
- Title:
- vby and BVI photometry of Omega Cen giants
- Short Name:
- J/AJ/127/980
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained photometric observations in a 182arcmin^2 area, 25' to the north of the center of the globular cluster {omega} Centauri. The Stroemgren vby and broadband BI filters were used to obtain measurements for some 2500 stars. Preliminary examinations of parts of the data have been presented previously (Hughes & Wallerstein, 2000, Cat. <J/AJ/119/1225>; Hughes, Wallerstein, & van Leeuwen, 2002, in ASP Conf. Ser. 265, 73). Here we present the complete data set, study the giant branches, and use the B-I color index as a tool for assessing the ages of the populations within {omega} Cen.
124. VPHAS+ DR2 survey
- ID:
- ivo://CDS.VizieR/II/341
- Title:
- VPHAS+ DR2 survey
- Short Name:
- II/341
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The primary goal of the VST Photometric H{alpha} Survey of the Southern Galactic Plane and Bulge (VPHAS+) is to collect single-epoch ugri broad-band and Ha narrow-band photometry across the southern Galactic Plane within the latitude range -5{deg}<b<+5{deg} down to point source magnitudes of ~21 or better. The VPHAS+ footprint also includes the inner Galactic Bulge, defined as a 20x20 deg^2^ box around the Galactic Centre: this assures optical coverage of the full VVV footprint. For all massive OBA stars this survey is deep enough to explore all but the most heavily obscured locations of the southern Plane, reaching to >4kpc from the Sun. These data will increase the number of known southern emission line stars by up to an order of magnitude, yielding much better statistics on important short-lived types of object. The wide-area uniform photometry obtained will also facilitate stellar population studies, capable of tracing structure over much of the southern Plane. VPHAS+ will trawl the star-formation history of the Galaxy as seen in stellar remnants of all types.
- ID:
- ivo://CDS.VizieR/J/AJ/148/51
- Title:
- WIYN Open Cluster. LXI. NGC 6819 photometry
- Short Name:
- J/AJ/148/51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- NGC 6819 is a richly populated, older open cluster situated within the Kepler field. A CCD survey of the cluster on the uvbyCaH{beta} system, coupled with proper-motion membership, has been used to isolate 382 highly probable, single-star unevolved main-sequence members over a 20' field centered on the cluster. From 278 F dwarfs with high precision photometry in all indices, a mean reddening of E(b-y)=0.117+/-0.005 or E(B-V)=0.160+/-0.007 is derived, where the standard errors of the mean include both internal errors and the photometric zero-point uncertainty. With the reddening fixed, the metallicity derived from the same 278 stars is [Fe/H]=-0.116+/-0.101 from m_1_ and -0.055+/-0.033 from hk, for a weighted average of [Fe/H]=-0.06+/-0.04, where the quoted standard errors of the mean include the internal errors from the photometric scatter plus the uncertainty in the photometric zero points. If metallicity is derived using individual reddening values for each star to account for potential reddening variation across the face of the cluster, the analogous result is unchanged. The cluster members at the turnoff of the color-magnitude diagram are used to test and confirm the recently discovered variation in reddening across the face of the cluster, with a probable range in the variation of {Delta}E(B-V)=0.045+/-0.015. With the slightly higher reddening and lower [Fe/H] compared to commonly adopted values, isochrone fitting leads to an age of 2.3+/-0.2Gyr for an apparent modulus of (m-M)=12.40+/-0.12.
- ID:
- ivo://CDS.VizieR/J/AJ/152/192
- Title:
- WOCS. LXXII. A uvbyCaHb study of NGC 2506
- Short Name:
- J/AJ/152/192
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Precision uvbyCaH{beta} photometry of the metal-deficient, old open cluster NGC2506 is presented. The survey covers an area of 20'*20' and extends to V~18 for b-y and H{beta} and to V~17.0 for c_1_ and hk. For V brighter than 16.0, photometric scatter among the indices leads to the recovery of six known variables within the cluster core and five new variables in the outer 5' of the survey field. Proper motions, radial velocities, and precise multicolor indices are used to isolate a highly probable sample of cluster members from the very rich color-magnitude diagram. From 257 highly probable members at the cluster turnoff, we derive a reddening estimate of E(b-y)=0.042+/-0.001 (E(B-V)=0.058+/-0.001), where the errors refer to the internal standard errors of the mean. [Fe/H] is derived from the A/F dwarf members using both m_1_ and hk, leading to [Fe/H]=-0.296+/-0.011 (sem) and -0.317+/-0.004 (sem), respectively. The weighted average, heavily dominated by hk, is [Fe/H]=-0.316+/-0.033. Based on red giant members, we place an upper limit of +/-0.010 on the variation in the reddening across the face of the cluster. We also identify two dozen potential red giant cluster members outside the cluster core. Victoria-Regina isochrones on the Stromgren system produce an excellent match to the cluster for an apparent modulus of (m-M)=12.75+/-0.1 and an age of 1.85+/-0.05Gyr.
