- ID:
- ivo://CDS.VizieR/J/A+A/365/370
- Title:
- Photometry of UCM galaxies. II.
- Short Name:
- J/A+A/365/370
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Johnson B surface photometry for the UCM Survey galaxies. One-dimensional bulge-disk decomposition is attempted, discussing on fitting functions and computational procedures. The results from this decomposition, jointly with concentration indices and an asymmetry coefficient, are employed to study the morphological properties of these galaxies. We also compare our results with the previous morphological classification established using Gunn r imaging data and with other samples of galaxies. No major statistical differences in morphology are found between red and blue data, although some characteristics such as size and luminosity concentration vary. We find a correlation between luminosity and size. Several parameters are used to segregate the objects according to their morphological type.
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- ID:
- ivo://CDS.VizieR/J/AJ/117/102
- Title:
- Photometry + Spectroscopy in HDF + Flanking Fields
- Short Name:
- J/AJ/117/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an HK' wide-field survey encompassing the Hubble Deep Field and its flanking fields. Our wide-field survey provides uniform coverage of a 61.8arcmin^2^ area to a depth equivalent to K=20.1 at 5{sigma}. We have also imaged the Hubble Deep Field in HK', providing uniform coverage of a 7.8arcmin^2^ area to a depth equivalent to K=21.2 at 5{sigma}. Using these data in combination with new deep University of Hawaii 8K V- and I-imaging obtained on the Canada-France-Hawaii Telescope, we find only a small population of objects with colors redder than an equivalent I-K=4mag, the color expected for an evolved elliptical galaxy at z>1. We infer that only a fraction of the local field elliptical galaxy population with M_K_<-23.4 could have formed in single bursts at high redshift. The HK' observations of the HDF and its flanking fields were made with the University of Hawaii 2.2m telescope (1996-02-06 to 1996-02-08 for the HDF, and 1997-04-17 to 1997-04-22 for the wider area) and the 3.6m Canada-France-Hawaii Telescope (CFHT, 1996-04-05 to 1996-04-08 for the HDF). The deep V- and I-band observations were made with the CFHT (1997-04-03 to 1997-04-08), and B-band observations with the Keck Low Resolution Imaging Spectrograph in a strip across the center of the HK wide-field image.
- ID:
- ivo://CDS.VizieR/J/ApJ/800/7
- Title:
- Physical conditions of high redshift DLAs
- Short Name:
- J/ApJ/800/7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new method is used to measure the physical conditions of the gas in damped Ly{alpha} systems (DLAs). Using high-resolution absorption spectra of a sample of 80 DLAs, we are able to measure the ratio of the upper and lower fine-structure levels of the ground state of C^+^ and Si^+^. These ratios are determined solely by the physical conditions of the gas. We explore the allowed physical parameter space using a Monte Carlo Markov chain method to constrain simultaneously the temperature, neutral hydrogen density, and electron density of each DLA. The results indicate that at least 5% of all DLAs have the bulk of their gas in a dense, cold phase with typical densities of ~100/cm3 and temperatures below 500K. We further find that the typical pressure of DLAs in our sample is log(P/k_B_)=3.4(K/cm3), which is comparable to the pressure of the local interstellar medium (ISM), and that the components containing the bulk of the neutral gas can be quite small with absorption sizes as small as a few parsecs. We show that the majority of the systems are consistent with having densities significantly higher than expected for a purely canonical warm neutral medium, indicating that significant quantities of dense gas (i.e., n_H_>0.1/cm3) are required to match observations. Finally, we identify eight systems with positive detections of Si II*. These systems have pressures (P/k_B_) in excess of 20000K/cm3, which suggest that these systems tag a highly turbulent ISM in young, star-forming galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/807/139
- Title:
- Physical parameters of compact SFGs in COSMOS field
- Short Name:
- J/ApJ/807/139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study on the physical properties of compact star-forming galaxies (cSFGs) with M_*_>=10^10^ M_{sun}_ and 2<=z<= 3 in the COSMOS (Cosmic Evolution Survey) and GOODS-S (Great Observatories Origins Deep Survey South) fields. We find that massive cSFGs have a comoving number density of (1.0+/-0.1)x10^-4^ Mpc^-3^. The cSFGs are distributed at nearly the same locus on the main sequence as extended star-forming galaxies (eSFGs) and dominate the high-mass end. On the rest-frame U-V versus V-J and U-B versus M_B_ diagrams, cSFGs are mainly distributed at the middle of eSFGs and compact quiescent galaxies (cQGs) in all colors, but are more inclined to "red sequence" than "green valley" galaxies. We also find that cSFGs have distributions similar to cQGs on the nonparametric morphology diagrams. The cQGs and cSFGs have larger Gini and smaller M_20_, while eSFGs have the reverse. About one-third of cSFGs show signatures of postmergers, and almost none of them can be recognized as disks. Moreover, those visually extended cSFGs all have lower Gini coefficients (Gini<0.4), indicating that the Gini coefficient could be used to clean out noncompact galaxies in a sample of candidate cSFGs. The X-ray-detected counterparts are more frequent among cSFGs than in eSFGs and cQGs, implying that cSFGs have previously experienced violent gas-rich interactions (such as major mergers or disk instabilities), which could trigger both star formation and black hole growth in an active phase.
- ID:
- ivo://CDS.VizieR/J/ApJS/228/9
- Title:
- Physical parameters of ~300000 SDSS-DR12 QSOs
- Short Name:
- J/ApJS/228/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the Sloan Digital Sky Survey (SDSS) Quasar Data Release 12 (DR12Q), containing nearly 300000 active galactic nuclei (AGNs), to calculate the monochromatic luminosities at 5100, 3000, and 1350{AA}, derived from the broadband extinction-corrected SDSS magnitudes. After matching these sources to their counterparts from the SDSS Quasar Data Release 7 (DR7Q), we find very high correlations between our luminosities and DR7Q spectra-based luminosities with minute mean offsets (~0.01dex) and dispersions of differences of 0.11, 0.10, and 0.12dex, respectively, across a luminosity range of 2.5dex. We then estimate the black hole (BH) masses of the AGNs using the broad line region radius-disk luminosity relations and the FWHM of the MgII and CIV emission lines, to provide a catalog of 283033 virial BH mass estimates (132451 for MgII, 213071 for CIV, and 62489 for both) along with the estimates of the bolometric luminosity and Eddington ratio for 0.1<z<5.5 and for roughly a quarter of the sky covered by SDSS. The BH mass estimates from Mg II turned out to be closely matched to the ones from DR7Q with a dispersion of differences of 0.34dex across a BH mass range of ~2dex. We uncovered a bias in the derived CIV FWHMs from DR12Q as compared to DR7Q, which we correct empirically. The CIV BH mass estimates should be used with caution because the CIV line is known to cause problems in the estimation of BH mass from single-epoch spectra. Finally, after the FWHM correction, the AGN BH mass estimates from CIV closely match the DR7Q ones (with a dispersion of 0.28dex), and more importantly the MgII and CIV BH masses agree internally with a mean offset of 0.07dex and a dispersion of 0.39dex.
- ID:
- ivo://CDS.VizieR/J/AJ/159/17
- Title:
- Physical properties of SFRs in NGC 3395/NGC 3396
- Short Name:
- J/AJ/159/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report long-slit spectroscopy of the early major merger galaxies NGC 3395/NGC 3396. The spectra are consistent with those for star-forming galaxies, but there is some indication of LINER-like active galactic nucleus activity in the center of NGC 3396. The total star formation rate in the regions observed is 2.83 M_{sun}_/yr, consistent with estimates for the entire galaxies. The highest abundances are in the centers of the galaxies, with the abundances decreasing with distance. There is a correlation between high abundance and high ionization parameter, both of which can be attributed to the presence of massive stars. Modeling with SB 99 indicates the star-forming regions are younger than 10 Myr. There are 1000-2000 WNL stars in the system, along with several thousand O stars, consistent with the ages of the star-forming regions. The highest electron densities are found in young regions with high star formation rates. The electron temperatures are higher than results for non-interacting galaxies, which is probably due to shock waves produced by the galaxy-galaxy interaction, the outflow of gas from massive stars, and/or collisions between gas clouds in the galaxies. There is star formation in the bridge of material between the galaxies. These regions are among the youngest in the system and have low abundances, suggesting the gas was pulled from the outer parts of the galaxies. X-ray point sources, probably high-mass X-ray binaries, are associated with several star-forming regions.
- ID:
- ivo://CDS.VizieR/J/AJ/141/137
- Title:
- Pittsburgh SDSS Mg II QSO catalog
- Short Name:
- J/AJ/141/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of intervening Mg II quasar absorption-line systems in the redshift interval 0.36<=z<=2.28. The catalog was built from Sloan Digital Sky Survey Data Release Four (SDSS DR4, Cat. II/267) quasar spectra. Currently, the catalog contains ~17000 measured Mg II doublets. We also present data on the ~44600 quasar spectra which were searched to construct the catalog, including redshift and magnitude information, continuum-normalized spectra, and corresponding arrays of redshift-dependent minimum rest equivalent widths detectable at our confidence threshold. The catalog is available online. A careful second search of 500 random spectra indicated that, for every 100 spectra searched, approximately one significant Mg II system was accidentally rejected. Current plans to expand the catalog beyond DR4 quasars are discussed. Many Mg II absorbers are known to be associated with galaxies. Therefore, the combination of large size and well understood statistics makes this catalog ideal for precision studies of the low-ionization and neutral gas regions associated with galaxies at low to moderate redshift. An analysis of the statistics of Mg II absorbers using this catalog will be presented in a subsequent paper.
- ID:
- ivo://CDS.VizieR/J/A+A/580/A95
- Title:
- Planck/AMI Sunyaev-Zel'dovich measurements
- Short Name:
- J/A+A/580/A95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations and analysis of a sample of 123 galaxy clusters from the 2013 Planck catalogue of Sunyaev-Zel'dovich sources with the Arcminute Microkelvin Imager (AMI), a ground-based radio interferometer. AMI provides an independent measurement with higher angular resolution, 3arcmin compared to the Planck beams of 5-10arcmin. The AMI observations thus provide validation of the cluster detections, improved positional estimates, and a consistency check on the fitted size ({theta}_s_) and flux (Y_tot_) parameters in the generalised Navarro, Frenk and White (GNFW) model. We detect 99 of the clusters. We use the AMI positional estimates to check the positional estimates and error-bars produced by the Planck algorithms PowellSnakes and MMF3. We find that Y_tot_ values as measured by AMI are biased downwards with respect to the Planck constraints, especially for high Planck-S/N clusters. We perform simulations to show that this can be explained by deviation from the universal pressure profile shape used to model the clusters. We show that AMI data can constrain the {alpha} and {beta} parameters describing the shape of the profile in the GNFW model for individual clusters provided careful attention is paid to the degeneracies between parameters, but one requires information on a wider range of angular scales than are present in AMI data alone to correctly constrain all parameters simultaneously.
- ID:
- ivo://CDS.VizieR/J/A+A/536/A8
- Title:
- Planck early results. VIII. ESZ sample.
- Short Name:
- J/A+A/536/A8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first all-sky sample of galaxy clusters detected blindly by the Planck satellite through the Sunyaev-Zeldovich (SZ) effect from its six highest frequencies. This early SZ (ESZ) sample is comprised of 189 candidates, which have a high signal-to-noise ratio ranging from 6 to 29. Its high reliability (purity above 95%) is further ensured by an extensive validation process based on Planck internal quality assessments and by external cross-identification and follow-up observations. Planck provides the first measured SZ signal for about 80% of the 169 previously-known ESZ clusters. Planck furthermore releases 30 new cluster candidates, amongst which 20 meet the ESZ signal-to-noise selection criterion. At the submission date, twelve of the 20 ESZ candidates were confirmed as new clusters, with eleven confirmed using XMM-Newton snapshot observations, most of them with disturbed morphologies and low luminosities. The ESZ clusters are mostly at moderate redshifts (86% with z below 0.3) and span more than a decade in mass, up to the rarest and most massive clusters with masses above 1x10^15^M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/ApJ/843/143
- Title:
- Polarimetry & photometry of GRB with RINGO2
- Short Name:
- J/ApJ/843/143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of early-time (~10^2^-10^4^s) photometry and polarimetry of all gamma-ray burst (GRB) optical afterglows observed with the RINGO2 imaging polarimeter on the Liverpool Telescope. Of the 19 optical afterglows observed, the following nine were bright enough to perform photometry and attempt polarimetry: GRB100805A, GRB101112A, GRB110205A, GRB110726A, GRB120119A, GRB120308A, GRB120311A, GRB120326A, and GRB120327A. We present multiwavelength light curves for these 9 GRBs, together with estimates of their optical polarization degrees and/or limits. We carry out a thorough investigation of detection probabilities, instrumental properties, and systematics. Using two independent methods, we confirm previous reports of significant polarization in GRB 110205A and 120308A, and report the new detection of P=6_-2_^+3^% in GRB101112A. We discuss the results for the sample in the context of the reverse- and forward-shock afterglow scenario, and show that GRBs with detectable optical polarization at early time have clearly identifiable signatures of reverse-shock emission in their optical light curves. This supports the idea that GRB ejecta contain large-scale magnetic fields, and it highlights the importance of rapid-response polarimetry.
