- ID:
- ivo://CDS.VizieR/J/A+A/533/A37
- Title:
- VI HST photometry of VV124 = UGC4879
- Short Name:
- J/A+A/533/A37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep V and I photometry of the isolated dwarf galaxy VV124=UGC4879, obtained from archival images taken with the Hubble Space Telescope - Advanced Camera for Surveys. In the color-magnitude diagrams of stars at distances larger than 40" from the center of the galaxy, we clearly identify for the first time a well-populated old Horizontal Branch (HB). We show that the distribution of these stars is more extended than that of Red Clump stars. This implies that very old and metal poor populations becomes more and more dominant in the outskirts of VV124. We also identify a massive (M=1.2+/-0.2x10^4^M_{sun}_) young (age=250+/-50Myr) star cluster (C1), as well as another of younger age (C2<~30+/-10Myr) with a mass similar to classical open clusters (M<=3.3+/-0.5x10^3^M_{sun}_). Both clusters lie at projected distances smaller than 100pc from the center of the galaxy.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/446/730
- Title:
- VIJK photometry of Whiting 1 stars
- Short Name:
- J/MNRAS/446/730
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Whiting 1 is a member of the fast-growing group of young globular clusters in the Milky Way halo. Preliminary estimates of its fundamental parameters have been provided using optical photometry and low-resolution spectroscopy. In an attempt to strengthen our knowledge of Whiting 1, in this study we employ a complementary approach. Isochrone fitting method was applied on the near-infrared colour-magnitude diagram and yields an age t=5.7+/-0.3Gyr, metallicity z=0.006+/-0.001 ([Fe/H]=-0.5+/-0.1) and distance modulus (m-M)0=17.48+/-0.10. Our results confirm that Whiting 1 is a young and moderately metal-rich globular cluster. It is one of the youngest from the Sgr dSph. We fitted an Elson, Fall and Freeman (EFF) profile to the near-infrared number counts, and measured cluster core radius r_c_=9.1+/-3.9". Two probable eclipsing variables in the cluster were found from multi-epoch V-band photometry. Finally, an unknown galaxy cluster was identified on our K versus (J-K) colour-magnitude diagram. It has a redshift z~1, and it is located at about 1arcmin from the centre of Whiting 1 at {alpha}_J2000_= 02:02:56.6, {delta}_J2000_=-03:16:09, contaminating the cluster photometry.
- ID:
- ivo://CDS.VizieR/II/343
- Title:
- VIKING catalogue data release 2
- Short Name:
- II/343
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The VIKING survey with VISTA (ESO programme ID 179.A-2004) is a wide area (eventually 1500 sq.degrees), intermediate-depth (5-sigma detection limit J=21 on Vega system) near-infrared imaging survey, in the five broadband filters Z, Y, J, H, Ks. The planned sky coverage is at high galactic latitudes, and includes two main stripes 70x10{deg}^2^ each: one in the South Galactic cap near Dec~-30{deg}, and one near Dec~0{deg} in the North galactic cap; in addition, there are two smaller outrigger patches called GAMA09 and CFHLS-W1. Science goals include z>6.5 quasars, extreme brown dwarfs, and multiwavelength coverage and identifications for a range of other imaging surveys, notably VST-KIDS and Herschel-ATLAS. This second public data release of VIKING data covers all of the highest quality data taken between the start of the survey (12th of November 2009) and the end of Period 92 (30th September 2013). This release supersedes the first release (VIKING and VIKING CAT published 28.06.2013 and 16.12.2013 respectively) as it includes improved CASU processing (V1.3) that gives better tile grouting and zero point corrections This release contains 396 tiles with coverage in all five VIKING filters, 379 of which have a deep co-add in J, and an additional 81 with at least two filters where the second OB has not been executed yet or one filter in an OB was poor quality. These 477 fields cover a total of ~690 square degrees and the resulting catalogues include a total of 46,270,162 sources (including low-reliability single-band detections). The imaging and catalogues (both single-band and band-merged) total 839.3GB. The coverage in each of the five sub-areas is not completely contiguous but any inter-tile gaps are relatively small. More details can be found in the accompanying documentation: viking_cat_dr2.pdf
- ID:
- ivo://CDS.VizieR/II/329
- Title:
- VIKING catalogue data release 1
- Short Name:
- II/329
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The VIKING survey with VISTA (ESO programme ID 179.A-2004) is a wide area (eventually 1500 sq.degrees), intermediate-depth (5-sigma detection limit J=21 on Vega system) near-infrared imaging survey, in the five broadband filters Z, Y, J, H, Ks. The planned sky coverage is at high galactic latitudes, and includes two main stripes 70x10{deg}^2^ each: one in the South Galactic cap near Dec~-30{deg}, and one near Dec~0{deg} in the North galactic cap; in addition, there are two smaller outrigger patches called GAMA09 and CFHLS-W1. Science goals include z>6.5 quasars, extreme brown dwarfs, and multiwavelength coverage and identifications for a range of other imaging surveys, notably VST-KIDS and Herschel-ATLAS. This first public data release of data taken between the 12th of November 2009 and the 13th of February 2011 includes 151 tiles with complete coverage in all five VIKING filters (55 in GAMA09/12/14, 91 in SGP and 5 in CFHLS-W1) i.e. 226 square degrees, and includes approximately 14,773,385 total sources (including low-reliability single-band detections) and the imaging and source lists total 314.4GB. The coverage in each of the five sub-areas is not completely contiguous but any inter-tile gaps are relatively small. More details can be found in the accompanying documentation: viking_cat_dr1.pdf
- ID:
- ivo://wfau.roe.ac.uk/vikingDR4-dsa
- Title:
- VIKING - VISTA Kilo-degree Infrared Galaxy survey Data Release 4
- Short Name:
- VIKING DR4
- Date:
- 04 Dec 2019 13:41:34
- Publisher:
- WFAU, Institute for Astronomy, University of Edinburgh
- Description:
- The VIKING survey is the VISTA counterpart to the VST KIDS survey. The KIDS survey will cover 1500 deg^2 in u,g,r,i divided in two stripes (NGP, centred on equator ; SGP, centred on Dec = -30). The matching VISTA survey will cover (almost) all of these stripes in Z,Y,J,H, Ks with ~ 400s exposures per band.
- ID:
- ivo://wfau.roe.ac.uk/vikingDR3-dsa
- Title:
- VIKING - VISTA Kilo-degree Infrared Galaxy survey Data Release 3
- Short Name:
- VIKING DR3
- Date:
- 04 Dec 2019 13:41:21
- Publisher:
- WFAU, Institute for Astronomy, University of Edinburgh
- Description:
- The VIKING survey is the VISTA counterpart to the VST KIDS survey. The KIDS survey will cover 1500 deg^2 in u,g,r,i divided in two stripes (NGP, centred on equator ; SGP, centred on Dec = -30). The matching VISTA survey will cover (almost) all of these stripes in Z,Y,J,H, Ks with ~ 400s exposures per band.
- ID:
- ivo://wfau.roe.ac.uk/vikingDR2-dsa
- Title:
- VIKING - VISTA Kilo-degree Infrared Galaxy survey Data Release 2
- Short Name:
- VIKING DR2
- Date:
- 04 Dec 2019 13:41:10
- Publisher:
- WFAU, Institute for Astronomy, University of Edinburgh
- Description:
- The VIKING survey is the VISTA counterpart to the VST KIDS survey. The KIDS survey will cover 1500 deg^2 in u,g,r,i divided in two stripes (NGP, centred on equator ; SGP, centred on Dec = -30). The matching VISTA survey will cover (almost) all of these stripes in Z,Y,J,H, Ks with ~ 400s exposures per band.
- ID:
- ivo://CDS.VizieR/J/ApJ/563/629
- Title:
- VIK' photometry and redshifts of galaxy clusters
- Short Name:
- J/ApJ/563/629
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze photometry and spectroscopy of a sample of 63 clusters at 0.3<=z<=0.9 drawn from the Las Campanas Distant Cluster Survey to empirically constrain models of cluster galaxy evolution. Our data originate from a variety of telescopes and instruments. The candidate galaxy clusters are identified using drift-scan images and techniques described briefly below for context but in full detail by Gonzalez et al. (2001, Cat. <J/ApJS/137/117>).
- ID:
- ivo://CDS.VizieR/J/ApJ/566/103
- Title:
- VIK' photometry and redshifts of galaxy clusters
- Short Name:
- J/ApJ/566/103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the influence of environment on brightest cluster galaxy (BCG) evolution using a sample of 63 clusters at 0.3<=z<=0.9 drawn primarily from the Las Campanas Distant Cluster Survey and follow-up V, I, and K' photometry. Our data originate from a variety of telescopes and instruments. The cluster sample and observations used here stem from deep optical and infrared follow-up imaging of a small subset of the full catalog that was obtained to aid in the classification of candidates and to develop photometric redshift indicators.
- ID:
- ivo://CDS.VizieR/J/ApJ/475/445
- Title:
- VIK photometry of faint field galaxies
- Short Name:
- J/ApJ/475/445
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We combine deep K-band (W. M. Keck Telescope) with V- and I-band (New Technology Telescope) observations of two "blank" high Galactic latitude fields, surveying a total of ~2arcmin^2^. The K-band number-magnitude counts continue to rise above K~22mag, reaching surface densities of few x10^5^deg^-2^. The slope for the galaxy counts is approximately [dlog(N)/dmag].deg^-2^=0.23+/-0.02 over the range 18-23mag. While this slope is consistent with other recent deep K-band surveys, there is a definite scatter in the normalisations by about a factor of 2. In particular, our normalisation is ~2x greater than the galaxy counts reported by Djorgovski et al. in 1995 (1995ApJ...438L..13D). Optical near-infrared color-magnitude and color-color diagrams for all objects detected in the V+I+K image are plotted and discussed in the context of grids of Bruzual-Charlot isochrone synthesis galaxy evolutionary models. The colors of most of the observed galaxies are consistent with a population drawn from a broad redshift distribution. A few galaxies at K~19-20 are red in both colors (V-I>3; I-K>2, consistent with being early-type galaxies having undergone a burst of star formation at z>5 and viewed at z~1. At K>20, we find several (approximately eight) "red outlier" galaxies with I-K>4 and V-I<2.5, whose colors are difficult to mimic by a single evolving or nonevolving stellar population at any redshift unless they either have quite low metallicity or are highly reddened. We compare the data against the evolutionary tracks of second-burst ellipticals and against a grid of models that does not constrain galaxy ages to a particular formation redshift. The red outliers' surface density is several per square arcminute, which is so high that they are probably common objects of low luminosity L<L*. Whether these are low-metallicity, dusty dwarf galaxies, or old galaxies at high redshift, they are curious and merit spectroscopic follow-up.