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- ID:
- ivo://CDS.VizieR/J/A+AS/118/111
- Title:
- BVRI photometry of 234 spiral galaxies
- Short Name:
- J/A+AS/118/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present V- and I-band CCD surface photometry on 234 inclined Sa-Sd galaxies, completed by similar data in B and R for a reduced subsample. In this first paper of a series, the reduction of the data is discussed, and several comparisons are made with other recent works. Radial profiles are presented for the surface brightness and the characteristics of ellipses fitted to isophotes; global, effective, and isophotal parameters are listed.
- ID:
- ivo://CDS.VizieR/J/A+AS/129/593
- Title:
- BVRI surface photometry for 14 Sb galaxies
- Short Name:
- J/A+AS/129/593
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Profiles of surface brightness, ellipticity and position angle obtained from CCD-BVRI images are presented for a sample of 14 spiral galaxies with 13<B_T_<16.1. For these galaxies, exponential disc components were fitted to the profiles. A decrease of disc scalelengths from B to I is found for 13 galaxies, while for one galaxy scalelengths increase from B to I. The scalelength ratios r_D(B)_/r_D(I)_, r_D(V)_/r_D(I)_ and r_D(R)_/r_D(I)_ show a systematic increase with increasing apparent ellipticity. The maximum variation is found for r_D(B)_/r_D(I)_ which is 80% larger for edge-on galaxies than for face-on galaxies.
- ID:
- ivo://CDS.VizieR/J/PASJ/55/1079
- Title:
- BVRi'z'JHKs photometry of ERO objects
- Short Name:
- J/PASJ/55/1079
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We studied the evolution of elliptical galaxies at z>~1 using a sample of 247 Extremely Red Objects (EROs) with R-Ks>3.35 (AB) and Ks<=22.1 (AB) constructed from BVRi'z'JHKs multicolor data of a 114arcmin^2^ area in the Subaru/XMM-Newton Deep Field taken with the Subaru Telescope and the UH 2.2m telescope. By fitting template spectra of old galaxies (OGs) and young, dusty starbursts (DSs) to the multicolor data, we classified EROs into these two classes and estimated their redshifts. We found that 58% of the EROs in our sample belong to the OG class and that these OGs have a wide range of colors at any redshift. We derived rest-frame B-band luminosity functions of OGs in our sample at z=1-1.5 and 1.5-2.5, and found that the number density of galaxies obeying passive evolution drops at z>~1.5 by a factor of three or more. The spatial correlation length of OGs is estimated to be r_0_>~8h^-1^Mpc, which is comparable to, or larger than, those of present-day early-type galaxies of similar luminosities. We also discussed properties of DSs in our data.
- ID:
- ivo://CDS.VizieR/J/ApJS/162/80
- Title:
- BVRJHKgr photometry of bright spiral galaxies
- Short Name:
- J/ApJS/162/80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometrically calibrated images and surface photometry in the B, V, R, J, H, and K bands of 25, and in the g, r, and K bands of five nearby bright (B^0^_T_<12.5 mag) spiral galaxies with inclinations of 30{deg}-65{deg} spanning the Hubble sequence from Sa to Scd. Data are from The Ohio State University Bright Spiral Galaxy Survey (Eskridge et al., Cat. <J/ApJS/143/73>), the Two Micron All Sky Survey (2006AJ....131.1163S), and the Sloan Digital Sky Survey Second Data Release (Abazajian et al., 2004AJ....128..502A). Radial surface brightness profiles are extracted, and integrated magnitudes are measured from the profiles. Axis ratios, position angles, and scale lengths are measured from the near-infrared images. A one-dimensional bulge/disk decomposition is performed on the near-infrared images of galaxies with a nonnegligible bulge component, and an exponential disk is fit to the radial surface brightness profiles of the remaining galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/382/60
- Title:
- BVR photometry in Abell 1689
- Short Name:
- J/A+A/382/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- At a redshift of 0.18, Abell 1689 is so far the most distant cluster of galaxies for which substantial mid-infrared (MIR) data have been published. Its mapping with the ISOCAM camera onboard the ISO satellite allowed the detection of 30 cluster members at 6.75{mu}m (LW2 filter) and 16 cluster members at 15{mu}m (LW3 filter) within a clustercentric radius of 0.5Mpc (Fadda et al., 2000A&A...361..827F, Paper I). We present here the follow-up optical photometric and spectroscopic observations which were used to study the individual properties of the galaxy members of A1689. We confirm the high fraction of blue galaxies initially reported in this rich cluster by Butcher & Oemler (1984ApJ...285..426B), that was challenged by some subsequent studies. We discuss the spectral and morphological properties of all cluster members in our spectroscopic sample, and of the MIR-detected galaxies in particular.
- ID:
- ivo://CDS.VizieR/J/A+AS/128/67
- Title:
- BVR photometry of Abell 85
- Short Name:
- J/A+AS/128/67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two catalogues of galaxies in the direction of the rich cluster ABCG 85. The first one includes 4232 galaxies located in a region +/-1{deg} from the cluster centre. It has been obtained from a list of more than 25000 galaxy candidates detected by scanning a Schmidt photographic plate taken in the B_J_ band. Positions are very accurate in this catalogue but magnitudes are not. This led us to perform CCD imaging observations in the V and R bands to calibrate these photographic magnitudes. A second catalogue (805 galaxies) gives a list of galaxies with CCD magnitudes in the V and R bands for a much smaller region in the centre of the cluster. These two catalogues will be combined with a redshift catalogue of 509 galaxies by Durret et al. (1997, subm.) to investigate the cluster properties at optical wavelengths Durret et al. (1997, subm.), as a complement to our previous X-ray studies (Pislar et al., 1997A&A...322...53P; Lima-Neto et al., 1997A&A...327...81L).
- ID:
- ivo://CDS.VizieR/J/AJ/109/173
- Title:
- BVR photometry of NGC 6822
- Short Name:
- J/AJ/109/173
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Our proposed method to study the star-formation histories in nearby irregulars is here applied to NGC 6822. To this purpose we have obtained accurate CCD photometry of three regions in the galaxy, reaching V=23.5 with the required accuracy of {sigma}_BVR_<=0.1mag. Major information on the stellar populations, star-formation rates, and initial mass functions of these regions in the last 1Gyr are derived from the comparison of the observational color-magnitude diagrams and luminosity functions with the corresponding synthetic diagrams and luminosity functions generated by a numerical simulation code based on stellar evolutionary tracks. We find that in the last 1Gyr the star-formation activity has been rather continuous, possibly occurring in long episodes of moderate activity separated by short quiescent periods, and that the initial mass function exponent a is in the vicinity of Salpeter's value, i.e., slightly flatter than in the solar neighborhood. The studied regions of NGC 6822 appear to contain different stellar populations. The preferred star formation regime for region A is a continuous activity coupled with a moderately flat {alpha}. For region C, instead, our best models suggest a discontinuous star formation and a moderately steep {alpha}. NGC 6822 is the last object of our original sample of five nearby irregulars. We can then draw the scenario resulting from this sample: most of the observed fields appear to have experienced a gasping regime of star formation, with average exponent {alpha}=2.35 for the initial mass function. Despite their small sizes, the majority of the sample galaxies contain different stellar populations in different regions.
- ID:
- ivo://CDS.VizieR/J/AJ/132/1593
- Title:
- BVR photometry of NGC 4594 globular clusters
- Short Name:
- J/AJ/132/1593
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A detailed imaging analysis of the globular cluster (GC) system of the Sombrero galaxy (NGC 4594) has been accomplished using a six-image mosaic from the Hubble Space Telescope Advanced Camera for Surveys. The quality of the data is such that contamination by foreground stars and background galaxies is negligible for all but the faintest 5% of the GC luminosity function. This enables the study of an effectively pure sample of 659 GCs until ~2mag fainter than the turnover magnitude, which occurs at M^TOM^_V_=-7.60+/-0.06 for an assumed m-M=29.77. Two GC metallicity subpopulations are easily distinguishable, with the metal-poor subpopulation exhibiting a smaller intrinsic dispersion in color compared to the metal-rich subpopulation.
- ID:
- ivo://CDS.VizieR/J/AJ/110/212
- Title:
- BVR photometry of stars in NGC 2366
- Short Name:
- J/AJ/110/212
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The stellar content of the Im galaxy NGC 2366 is discussed on the basis of CCD BVR photometry. The three brightest blue and red stars have been used to estimate its distance, obtaining a value of 2.9pc. The spatial distribution of the young stellar population is discussed in the light of the integrated color indices and the color-magnitude diagrams of different zones of the galaxy. A generalized star formation burst seems to have taken place about 50Myr ago. The youngest stars are preferentially formed in the South-West part of the bar, where the giant H II complex NGC 2363 is located, being younger and bluer. The bar seems to play a role favoring star formation in one of its extremes. Self-propagation however, does not seem to be triggering star formation at large scale. A small region, populated by very young stars has also been found at the East of the galaxy.
