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- ID:
- ivo://CDS.VizieR/J/A+A/439/487
- Title:
- Nuker law fits of radio galaxies
- Short Name:
- J/A+A/439/487
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Nuker law fits of brightness profiles of a number of radio galaxies that were observed with the HST. The data on B2 radio galaxies were described in Capetti et al. (2000A&A...362..871C), while a number of 3C galaxies with FR II radio structure were taken from the HST archive. The profiles are compared with other samples of early type galaxies, taken from the literature. We find that radio galaxies always have "core"-type profiles, i.e. a shallow profile in the inner part of the galaxy, while radio-quiescent ellipticals may either have "core"-type or "power-law" type profiles.
- ID:
- ivo://CDS.VizieR/J/ApJ/664/226
- Title:
- Nuker law parameters of early-type galaxies
- Short Name:
- J/ApJ/664/226
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We combine several HST investigations on the central structure of early-type galaxies to generate a large sample of surface photometry. The studies selected were those that used the "Nuker law" to characterize the inner light distributions of the galaxies. The sample comprises WFPC1 and WFPC2 V-band observations published earlier by our group, R-band WFPC2 photometry of Rest et al. (2001AJ....121.2431R), NICMOS H-band photometry by Ravindranath et al. (2001AJ....122..653R) and Quillen et al. (2000ApJS..128...85Q), and the brightest cluster galaxy WFPC2 I-band photometry of Laine et al. (2003, Cat. J/AJ/125/478).
- ID:
- ivo://CDS.VizieR/J/MNRAS/472/4878
- Title:
- Number counts predictions for surveys
- Short Name:
- J/MNRAS/472/4878
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We estimate the number counts of line emitters at high redshift and their evolution with cosmic time based on a combination of photometry and spectroscopy. We predict the H{alpha}, H{beta}, [OII], and [OIII] line fluxes for more than 35000 galaxies down to stellar masses of ~10^9^M_{sun}_ in the COSMOS and GOODS-S fields, applying standard conversions and exploiting the spectroscopic coverage of the FMOS-COSMOS survey at z~1.55 to calibrate the predictions. We calculate the number counts of H{alpha}, [OII], and [OIII] emitters down to fluxes of 1x10^-17^erg/cm^2^/s in the range 1.4<z<1.8 covered by the FMOS-COSMOS survey. We model the time evolution of the differential and cumulative H{alpha} counts, steeply declining at the brightest fluxes. We expect ~9300-9700 and ~2300-2900-galaxies/deg^2^ for fluxes >=1x10^-16^ and >=2x10^-16^erg/cm^2^/s over the range of 0.9<z<1.8. We show that the observed evolution of the main sequence of galaxies with redshift is enough to reproduce the observed counts variation at 0.2<z<2.5. We characterize the physical properties of the H{alpha} emitters with fluxes >=2x10^-16^erg/cm^2^/s including their stellar masses, UV sizes, [NII]/H{alpha} ratios and H{alpha} equivalent widths. An aperture of R~R_e_~0.5arcsec maximizes the signal-to-noise ratio for a detection, whilst causing a factor of ~2x flux losses, influencing the recoverable number counts, if neglected. Our approach, based on deep and large photometric data sets, reduces the uncertainties on the number counts due to the selection and spectroscopic samplings whilst exploring low fluxes. We publicly release the line flux predictions for the explored photometric samples.
- ID:
- ivo://CDS.VizieR/J/A+A/602/A96
- Title:
- Number counts produced by the EGG
- Short Name:
- J/A+A/602/A96
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper introduces egg, the Empirical Galaxy Generator, a tool designed within the ASTRODEEP collaboration to generate mock galaxy catalogs for deep fields with realistic fluxes and simple morphologies. The simulation procedure is based exclusively on empirical prescriptions - rather than first principles - to provide the most accurate match with current observations at 0<z<7. We considered that galaxies can be either quiescent or star-forming, and used their stellar mass (M*) and redshift (z) as the fundamental properties from which all the other observables can be statistically derived. Drawing z and M* from the observed galaxy stellar mass functions, a star-formation rate (SFR) is attributed to each galaxy from the tight SFR-M* main sequence, while dust attenuation, optical colors and simple disk plus bulge morphologies are obtained from empirical relations that we established from the high quality Hubble and Herschel observations from the CANDELS fields. Random scatter was introduced in each step to reproduce the observed distributions of each parameter. Based on these observables, an adequate panchromatic spectral energy distribution (SED) is selected for each galaxy and synthetic photometry is produced by integrating the redshifted SED in common broad-band filters. Finally, the mock galaxies are placed on the sky at random positions with a fixed angular two-point correlation function to implement basic clustering. The resulting flux catalogs reproduce accurately the observed number counts in all broad bands from the ultraviolet up to the sub-millimeter, and can be directly fed to image simulators such as SkyMaker. The images can then be used to test source extraction softwares and image-based techniques such as stacking. egg is open-source, and is made available to the community on behalf of the ASTRODEEP collaboration, together with a set of pre-generated catalogs and images.
- ID:
- ivo://CDS.VizieR/J/MNRAS/385/2097
- Title:
- NUV-J colours of red-sequence galaxies
- Short Name:
- J/MNRAS/385/2097
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present GALEX near-ultraviolet (NUV) and Two-Micron All-Sky Survey J-band photometry for red-sequence galaxies in local clusters. We define quiescent samples according to a strict emission threshold, removing galaxies with very recent star formation. We analyse the NUVJ colour-magnitude relation (CMR) and find that the intrinsic scatter is an order of magnitude larger than for the analogous optical CMR (~0.35 rather than 0.05mag), in agreement with previous studies. Comparing the NUVJ colours with spectroscopically derived stellar population parameters, we find a strong (>5.5sigma) correlation with metallicity, only a marginal trend with age, and no correlation with the alpha/Fe ratio. We explore the origin of the large scatter and conclude that neither aperture effects nor the UV upturn phenomenon contribute significantly. We show that the scatter could be attributed to simple 'frosting' by either a young or a low-metallicity subpopulation.
- ID:
- ivo://CDS.VizieR/J/AJ/138/598
- Title:
- NUV sources in Hubble Ultra Deep Field
- Short Name:
- J/AJ/138/598
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog from the first high-resolution U-band image of the Hubble Ultra Deep Field, taken with Hubble's Wide-Field Planetary Camera 2 through the F300W filter, is presented. We detect 96 U-band objects and compare and combine this catalog with a Great Observatories Origins Deep Survey B-selected catalog that provides B, V, i, and z photometry, spectral types, and photometric redshifts. We have also obtained far-ultraviolet (FUV, 1614{AA}) data with Hubble's Advanced Camera for Surveys Solar Blind Channel (ACS/SBC) and with GALEX. We detected 31 sources with ACS/SBC, 28 with GALEX/FUV, and 45 with GALEX/NUV. The methods of observations, image processing, object identification, catalog preparation, and catalog matching are presented.
- ID:
- ivo://CDS.VizieR/J/AJ/105/499
- Title:
- OB Associations and Spiral Structure in M33
- Short Name:
- J/AJ/105/499
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This file contains UBV photometry for the brightest stars in the southern spiral arm of M33. All stars brighter than V=21 are included in this file. For details on the observations and data reduction see reference. All the data is in ASCII format of the file. The observations where carried out on the Palomar 60in. telescope.
- ID:
- ivo://CDS.VizieR/J/A+A/502/1015
- Title:
- OB associations in IC 1613
- Short Name:
- J/A+A/502/1015
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Determining the parameters of massive stars is crucial to understand many processes in galaxies and the Universe, since these objects are important sources of ionization, chemical enrichment and momentum. 10m class telescopes enable us to perform detailed quantitative spectroscopic analyses of massive stars in other galaxies, sampling areas of different metallicity. Relating the stars to their environment is crucial to understand the physical processes ruling their formation and evolution. In preparation for the new instrumentation planned for the Gran Telescopio CANARIAS (GTC), our goal is to build a list of massive star candidates in the metal-poor irregular galaxy IC 1613. The catalogue must have very high astrometric accuracy, suitable for the current generation of multi-object spectrographs. A census of OB associations in this galaxy is also needed, to provide important additional information about the age and environment of the candidate OB stars.
2610. OB associations in M31
- ID:
- ivo://CDS.VizieR/J/ApJS/98/595
- Title:
- OB associations in M31
- Short Name:
- J/ApJS/98/595
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Images of the central and southern parts of the local group Sb spiral galaxy M31 were obtained by the Ultraviolet Imaging Telescope during the Astro-1 Spacelab mission. Stellar photometry is obtained for 611 stars in 59 van den Bergh associations in the near-UV A1 band (central wavelength 2490A), and for 130 of these stars in the far-UV B1 band (central wavelength 1520A). In addition, B-band magnitudes for 456 of the stars in ~30 associations, together with U- and R-band photometry for ~290 stars in ~15 associations are determined from CCD images. B-magnitudes from the catalog of Magnier et al. (1992A&AS...96..379M) are given for 137 stars and R-magnitudes for 233 stars. Stellar positions are obtained from the ground-based CCD images and from UIT images. Total fluxes in the UV bands are measured for 63 associations. Finding charts are presented in the NUV and FUV bands, as well as one optical band. Tables give the images utilized in this investigation, the associations observed, with positions, total UV fluxes, extinctions estimated from color-magnitude diagrams, and stellar positions with photometry in up to five bands. UV color magnitude diagrams are presented with extinctions estimated by comparing the observed association color magnitude diagrams with colors and magnitudes of early-type stars computed from the IUE spectral atlas of Fanelli et al. (1992ApJS...82..197F). Comparison with evolutionary models suggests a maximum initial mass ~85M_{sun}_. Ultraviolet extinction within most M31 OB associations is found to follow an extinction curve similar to that of Hutchings et al. (1992ApJ...400L..35H). The variation in the fraction of near-UV stars also measured in the far-UV among the associations is probably caused by variations in age, extinction, and the degree of foreground contamination.
