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7851. VIPERS Multi-Lambda Survey
ID:
ivo://CDS.VizieR/J/A+A/590/A102
Title:
VIPERS Multi-Lambda Survey
Short Name:
J/A+A/590/A102
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present observations collected in the CFHTLS-VIPERS region in the ultraviolet with the GALEX satellite (far- and near-ultraviolet channels) and in the near-infrared with the CFHT/WIRCam camera (Ks band) over an area of 22 and 27deg^2^, respectively. The depth of the photometry was optimised to measure the physical properties (e.g., star formation rate, stellar masses) of all the galaxies in the VIPERS spectroscopic survey. The large volume explored by VIPERS will enable a unique investigation of the relationship between the galaxy properties and their environment (density field and cosmic web) at high redshift (0.5<=z<=1.2). In this paper, we present the observations, the data reductions, and the build-up of the multi-colour catalogues. The CFHTLS-T0007 (gri-{chi}^2^) images are used as reference to detect and measure the Ks -band photometry, while the T0007 u*-selected sources are used as priors to perform the GALEX photometry based on a dedicated software (EMphot). Our final sample reaches NUV_AB_~25 (at 5{sigma}) and K_AB_~22 (at 3{sigma}). The large spectroscopic sample (~51,000 spectroscopic redshifts) allows us to highlight the robustness of our star/galaxy separation and the reliability of our photometric redshifts with a typical accuracy of {sigma]_z_<=0:04 and a fraction of catastrophic failures {eta}<=2% down to i~23. We present various tests on the Ks -band completeness and photometric redshift accuracy by comparing our results with existing overlapping deep photometric catalogues. Finally, we discuss the BzK sample of passive and active galaxies at high redshift and the evolution of galaxy morphology in the (NUV-r) vs (r-Ks) diagram at low redshift (z<=0.25) based on the high image quality of the CFHTLS. The images, catalogues, and photometric redshifts for 1.5 million sources (down to NUV<=25 {union} Ks<=22) are released and available at this URL: http://cesam.lam.fr/vipers-mls/.
7852. VI photometry and spectroscopy in h+{chi} Per
ID:
ivo://CDS.VizieR/J/ApJS/186/191
Title:
VI photometry and spectroscopy in h+{chi} Per
Short Name:
J/ApJS/186/191
Date:
21 Oct 2021
Publisher:
CDS
Description:
From photometric observations of ~47000 stars and spectroscopy of ~11000 stars, we describe the first extensive study of the stellar population of the famous Double Cluster, h and {chi} Persei, down to subsolar masses. By analyzing optical spectra and optical/infrared photometry, we constrain the distance moduli (dM), reddening (E(B-V)), and ages for h Persei, {chi} Persei, and the low-density halo population surrounding both cluster cores. With the exception of mass and spatial distribution, the clusters are nearly identical in every measurable way. From these data, we establish the first spectroscopic and photometric membership lists of cluster stars down to early/mid M dwarfs. At minimum, there are ~5000 members within 10' of the cluster centers, while the entire h and {chi} Persei region has at least ~13000 and as many as 20000 members. The Double Cluster contains ~8400M_{sun}_ of stars within 10' of the cluster centers. We estimate a total mass of at least 20000M_{sun}_. We conclude our study by outlining outstanding questions regarding the past and present properties of h and {chi} Persei. From comparing recent work, we compile a list of intrinsic colors and derive a new effective temperature scale for O-M dwarfs, giants, and supergiants.
7853. VI Photometry and Variables in NGC 3201
ID:
ivo://CDS.VizieR/J/AJ/123/279
Title:
VI Photometry and Variables in NGC 3201
Short Name:
J/AJ/123/279
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Globular Cluster NGC 3201 was monitored for the existence of variable stars with 16.5<V<20 and 0.2days<period<5days. The files v*.dat contain time-series photometry data in V and I for the 14 variables detected in the field of NGC 3201. Only V6 (a blue straggler contact binary) is a member of the cluster. Due to its low-latitude position, interstellar extinction is present across the field of the cluster. The file phot.dat contains VI photometry data on the monitored stars. These data are NOT corrected for extinction. The variables V7, V8, and V9 were discovered during a follow-up observing run with a different telescope and therefore do not lie in the field covered by phot.dat. Variables V1-V9 are contact system eclipsing binaries, V10 is an RR Lyrae, V11 a semi-detached Algol type binary, V12 a detached binary system, and V13 and V14 are unclassified variable systems.
7854. VI photometry and velocity map of NGC 6388
ID:
ivo://CDS.VizieR/J/A+A/533/A36
Title:
VI photometry and velocity map of NGC 6388
Short Name:
J/A+A/533/A36
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from ground based VLT/FLAMES spectroscopy in combination with HST data for the globular cluster NGC 6388. The aim of this work is to probe whether this massive cluster hosts an intermediate-mass black hole at its center and to compare the results with the expected value predicted by the M-{sigma} scaling relation.
7855. VI photometry in 3 dwarf galaxies
ID:
ivo://CDS.VizieR/J/A+A/615/A96
Title:
VI photometry in 3 dwarf galaxies
Short Name:
J/A+A/615/A96
Date:
21 Oct 2021
Publisher:
CDS
Description:
The abundance and spatial distribution of dwarf galaxies are excellent empirical benchmarks against which to test models of structure formation on small scales. The nearby Centaurus group, with its two subgroups centered on Cen A and M 83, stands out as an important alternative to the Local Group for scrutinizing cosmological model predictions in a group of galaxies context. We have obtained deep optical images of three recently discovered M 83 satellite galaxy candidates with the FORS2 instrument mounted on the Very Large Telescope. We aim to confirm their group membership and study their stellar population. Deep V I-band photometry was used to resolve the brightest stars in our targets. Artificial star tests are performed to estimate the completeness and uncertainties of the photometry. The color-magnitude diagrams reveal the red giant branch (RGB) stars, allowing us to use the Sobel edge detection method to measure the magnitude of the RGB tip and thus derive distances and group membership for our targets. The mean metallicity of the dwarf galaxies were further determined by fitting BASTI model isochrones to the mean RGB locus.
7856. VI Photometry in M54 and Sgr Dwarf Galaxy
ID:
ivo://CDS.VizieR/J/AJ/109/1086
Title:
VI Photometry in M54 and Sgr Dwarf Galaxy
Short Name:
J/AJ/109/1086
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present VI CCD color-magnitude diagrams for the globular cluster M54 and the Sagittarius dwarf galaxy. These are used to derive the following quantities: [Fe/H] = -1.79 +/- 0.08 for M54 and [Fe/H] = -0.52 +/- 0.09 for Sagittarius. We find a metallicity dispersion of +/- 0.16 dex in M54, and we infer the possible existence of a [Fe/H] ~ -1.3 component in Sagittarius, which may have a metallicity dispersion as well. The mean reddening in the direction of M54 is E(B-V) = 0.13 +/- 0.02. The distances to M54 and Sagittarius, determined using their horizontal branch magnitudes, are identical to within the uncertainties of existing RR Lyrae luminosity-abundance relations. This, together with positional and radial velocity arguments, suggests that M54 is physically associated with Sagittarius. We note that M54 is substantially brighter than the globular cluster members of the Fornax dwarf spheroidal galaxy, and that the metal abundance of Sagittarius is quite high for its estimated absolute magnitude.
7857. VI Photometry in M81 Group
ID:
ivo://CDS.VizieR/J/A+A/396/473
Title:
VI Photometry in M81 Group
Short Name:
J/A+A/396/473
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive quantitative star formation histories of the four suspected tidal dwarf galaxies in the M 81 group, Holmberg IX, BK3N, Arp-loop (A0952+69), and Garland, using Hubble Space Telescope/Wide Field Planetary Camera 2 images in F606W and F814W obtained as part of a Snapshot survey of dwarf galaxies in the Local Universe.
7858. VI photometry in M33 outer regions
ID:
ivo://CDS.VizieR/J/AJ/128/224
Title:
VI photometry in M33 outer regions
Short Name:
J/AJ/128/224
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep CCD photometry in the VI passbands using the WIYN 3.5m telescope of a field located approximately 20 southeast of the center of M33; this field includes the region studied by Mould & Kristian in 1986ApJ...305..591M. The color-magnitude diagram (CMD) extends to I~25 and shows a prominent red giant branch (RGB), along with significant numbers of asymptotic giant branch and young main-sequence stars.
7859. VI photometry in NGC 188
ID:
ivo://CDS.VizieR/J/A+A/390/961
Title:
VI photometry in NGC 188
Short Name:
J/A+A/390/961
Date:
21 Oct 2021
Publisher:
CDS
Description:
We used HST-WFPC2 to study the white dwarf luminosity function of the old open cluster NGC 188 in order to determine a lower limit to the age of the cluster (~5Gyr) by looking at the faint end of the cooling sequence (down to V~26.5).
7860. VI photometry in NGC 6352
ID:
ivo://CDS.VizieR/J/AJ/110/652
Title:
VI photometry in NGC 6352
Short Name:
J/AJ/110/652
Date:
21 Oct 2021
Publisher:
CDS
Description:
The globular cluster NGC 6352, which on the basis of its Galactic position, radial velocity, and [Fe/H] is a member of the (thick) disk system of globular clusters, has been observed to below the main-sequence turnoff (MSTO) using the Hubble Space Telescope. These observations, which were obtained before the repair mission, were analyzed using the flux-conserving iterative/recursive deconvolution algorithm developed at the University of North Carolina. This algorithm can produce more precise photometry than standard PSF-fitting methods with the aberrated images. The V, (V-Ic) color-magnitude diagram constructed from these observations places the cluster turnoff at V=18.80+/-0.10. Observations with the CTIO 0.9m telescope have been used to photometer the brighter stars in the cluster, providing a calibration of the HST data and an estimate of the cluster's reddening, E(B-V)=0.21+/-0.03. From spectroscopic observations of the strengths of the Ca II triplet lines in red giants in the cluster and from previous measurements in the literature, we find that NGC 6352 is only slightly more metal rich (Delta[Fe/H]=0.08+/-0.05) than the prototypical disk globular cluster, 47 Tuc. From the difference in V magnitude between the horizontal branch and the MSTO, we find that NGC 6352 is essentially the same age as 47 Tuc (formally, older by 0.7+/-2.2Gyr). Comparisons with the latest Yale isochrones support this result and yield 14.5+/-2Gyr for the age of 47 Tuc from the photometry of Hesser et al. (1987PASP...99..739H), which is consistent with other determinations. The old age obtained for NGC 6352 provides additional evidence that the disk system of globular clusters is very old and is in fact older or comparable in age to several globular clusters populating the Galactic halo.