- ID:
- ivo://CDS.VizieR/J/ApJ/641/78
- Title:
- CIV variability in 105 SDSS quasars
- Short Name:
- J/ApJ/641/78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine the variability of the high-ionization CIV {lambda}1549 line in a sample of 105 quasars observed at multiple epochs by the Sloan Digital Sky Survey. We find a strong correlation between the change in the CIV line flux and the change in the line width, but no correlations between the change in flux and changes in line center and skewness. The relation between line flux change and line width change is consistent with a model in which a broad line base varies with greater amplitude than the line core. The objects studied here are more luminous and at higher redshift than those normally studied for variability, ranging in redshift from 1.65 to 4.00 and in absolute r-band magnitude from roughly -24 to -28.
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- ID:
- ivo://CDS.VizieR/J/ApJS/237/31
- Title:
- CLAMATO DR1: 3D Ly{alpha} forest tomography
- Short Name:
- J/ApJS/237/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Faint star-forming galaxies at z~2-3 can be used as alternative background sources to probe the Ly{alpha} forest in addition to quasars, yielding high sightline densities that enable 3D tomographic reconstruction of the foreground absorption field. Here, we present the first data release from the COSMOS Ly{alpha} Mapping And Tomography Observations (CLAMATO) Survey, which was conducted with the LRIS spectrograph on the Keck I telescope. Over an observational footprint of 0.157deg^2^ within the COSMOS field, we used 240 galaxies and quasars at 2.17<z<3.00, with a mean comoving transverse separation of 2.37h^-1^Mpc, as background sources probing the foreground Ly{alpha} forest absorption at 2.05<z<2.55. The Ly{alpha} forest data was then used to create a Wiener-filtered tomographic reconstruction over a comoving volume of 3.15x10^5^h^-3^Mpc^3^ with an effective smoothing scale of 2.5h^-1^Mpc. In addition to traditional figures, this map is also presented as a virtual-reality visualization and manipulable interactive figure. We see large overdensities and underdensities that visually agree with the distribution of coeval galaxies from spectroscopic redshift surveys in the same field, including overdensities associated with several recently discovered galaxy protoclusters in the volume. Quantitatively, the map signal-to-noise is S/N^wiener^~3.4 over a 3h^-1^Mpc top-hat kernel based on the variances estimated from the Wiener filter. This data release includes the redshift catalog, reduced spectra, extracted Ly{alpha} forest pixel data, and reconstructed tomographic map of the absorption.
- ID:
- ivo://CDS.VizieR/J/ApJ/671/1503
- Title:
- Cl 0024+16 and MS 0451-03 spectrophotometry
- Short Name:
- J/ApJ/671/1503
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new results from our comparative survey of two massive, intermediate-redshift galaxy clusters, Cl 0024+17 (z=0.39) and MS 0451-03 (z=0.54). Combining optical and UV imaging with spectroscopy of member galaxies, we identify and study several key classes of "transition objects" whose stellar populations or dynamical states indicate a recent change in morphology and star formation rate. For the first time, we have been able to conclusively identify spiral galaxies in the process of transforming into S0 galaxies. This has been accomplished by locating both spirals whose star formation is being quenched and their eventual successors, the recently created S0s.
- ID:
- ivo://CDS.VizieR/J/ApJS/68/715
- Title:
- Clark Lake 30.9MHz survey
- Short Name:
- J/ApJS/68/715
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Galactic plane has been mapped at 30.9 MHz with the Clark Lake TPT telescope giving unprecedented resolution for such a low frequency. The synthetized beam is 13.0'x11.1' at the zenith. Contour maps and a source list are presented for the regions 350deg<l<59deg, 84deg<l<97deg, and 133deg<l<250deg, with |b|<2deg-3deg. The source list contains integrated flux densities and positions for 702 discrete emission regions. Sensitivity is confusion-limited and varies from ~ 5Jy/beam in the inner Galaxy to ~ 1-2Jy/beam toward the outer Galaxy.
- ID:
- ivo://CDS.VizieR/J/A+A/640/A65
- Title:
- CLASH brightest cluster galaxies CO spectra
- Short Name:
- J/A+A/640/A65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Brightest cluster galaxies (BCGs) are excellent laboratories to study galaxy evolution in dense Mpc-scale environments. We have observed in CO(1->0), CO(2->1), CO(3->2), or CO(4->3), with the IRAM-30m, 18 BCGs at z~0.2-0.9 that are drawn from the Cluster Lensing And Supernova survey with Hubble (CLASH) survey. Our sample includes RX1532, which is our primary target, being among the BCGs with the highest star formation rate (SFR>~100M_{sun}_/yr) in the CLASH sample. We unambiguously detected both CO(1->0) and CO(3->2) in RX1532, yielding a large reservoir of molecular gas, M_H2_=(8.7+/-1.1)10^10^M_{sun}_, and a high level of excitation r31=0.75+/-0.12. A morphological analysis of the Hubble Space Telescope I-band image of RX1532 reveals the presence of clumpy substructures both within and outside the half-light radius re=(11.6+/-0.3)kpc, similarly to those found independently both in ultraviolet and in H in previous work. We tentatively detected CO(1->0) or CO(2->1) in four other BCGs, with molecular gas reservoirs in the range M_H2_=2x10^10-11^M_{sun}_. For the remaining 13 BCGs we set robust upper limits of M_H2_/M*<~0.1, which are among the lowest molecular gas to stellar mass ratios found for distant ellipticals and BCGs. By comparison with distant cluster galaxies observed in CO our study shows that RX1532 (M_H2_/M*=0.40+/-0.05) belongs to the rare population of star forming and gas-rich BCGs in the distant universe. By using available X-ray based estimates of the central intra-cluster medium entropy, we show that the detection of large reservoirs of molecular gas M_H2_>~10^10^M_{sun}_ in distant BCGs is possible when the two conditions are met: i) high SFR and ii) low central entropy, which favors the condensation and the inflow of gas onto the BCGs themselves, similarly to what has been previously found for some local BCGs.
- ID:
- ivo://CDS.VizieR/J/MNRAS/470/95
- Title:
- CLASH galaxies photometric redshifts in 25 ClG
- Short Name:
- J/MNRAS/470/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present accurate photometric redshifts for galaxies observed by the Cluster Lensing And Supernova survey with Hubble (CLASH). CLASH observed 25 massive galaxy cluster cores with the Hubble Space Telescope in 16 filters spanning 0.2-1.7{mu}m. Photometry in such crowded fields is challenging. Compared to our previously released catalogues, we make several improvements to the photometry, including smaller apertures, intracluster light subtraction, point spread function matching and empirically measured uncertainties. We further improve the Bayesian photometric redshift estimates by adding a redder elliptical template and by inflating the photometric uncertainties of the brightest galaxies. The resulting photometric redshift accuracies are dz/(1+z)~0.8, 1.0 and 2.0 per cent for galaxies with I-band F814W AB magnitudes <18, 20 and 23, respectively. These results are consistent with our expectations. They improve on our previously reported accuracies by a factor of 4 at the bright end and a factor of 2 at the faint end. Our new catalogue includes 1257 spectroscopic redshifts, including 382 confirmed cluster members. We also provide stellar mass estimates. Finally, we include lensing magnification estimates of background galaxies based on our public lens models. Our new catalogue of all 25 CLASH clusters is available via Mikulski Archive for Space Telescopes. The analysis techniques developed here will be useful in other surveys of crowded fields, including the Frontier Fields and surveys carried out with Javalambre-Physics of the Accelerated Universe Astrophysical Survey and James Webb Space Telescope.
- ID:
- ivo://CDS.VizieR/J/ApJ/762/L30
- Title:
- CLASH: MCS J0416.1-2403 strong lensing analysis
- Short Name:
- J/ApJ/762/L30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We perform a strong lensing analysis of the merging galaxy cluster MACS J0416.1-2403 (M0416; z=0.42) in recent CLASH/HST observations. We identify 70 new multiple images and candidates of 23 background sources in the range 0.7<~z_phot_<~6.14 including two probable high-redshift dropouts, revealing a highly elongated lens with axis ratio =~5:1, and a major axis of ~100" (z_s_~2). Compared to other well-studied clusters, M0416 shows an enhanced lensing efficiency. Although the critical area is not particularly large (=~0.6{squ}'; z_s_~2), the number of multiple images, per critical area, is anomalously high. We calculate that the observed elongation boosts the number of multiple images, per critical area, by a factor of ~2.5x, due to the increased ratio of the caustic area relative to the critical area. Additionally, we find that the observed separation between the two main mass components enlarges the critical area by a factor of ~2. These geometrical effects can account for the high number (density) of multiple images observed. We find in numerical simulations that only ~4% of the clusters (with M_vir_>=6x10^14^h^-1^M_{sun}_) exhibit critical curves as elongated as in M0416.
- ID:
- ivo://CDS.VizieR/J/A+A/562/A86
- Title:
- CLASH. Photometric + photo-z catalog
- Short Name:
- J/A+A/562/A86
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Cluster Lensing And Supernovae survey with Hubble (CLASH) is a Hubble Space Telescope (HST) Multi-Cycle Treasury programme that observes 25 massive galaxy clusters, 20 of which were X-ray-selected to preferably choose dynamically relaxed clusters, and 5 additional "high magnification" clusters, which were selected based on their optical lensing properties. CLASH aims to study the dark matter distribution of the clusters and find magnified high-redshift galaxies behind them. CLASH observations were carried out in 16 bands from UV to NIR to derive accurate and reliable estimates of photometric redshifts. We present the CLASH photometric redshifts using 16 HST bands and study the photometric redshift accuracy including a detailed comparison between photometric and spectroscopic redshifts for the strong lensing arcs using the measurements from the cluster MACSJ1206.2-0847.
- ID:
- ivo://CDS.VizieR/J/ApJS/199/25
- Title:
- CLASH sources for MACS1149.6+2223
- Short Name:
- J/ApJS/199/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Cluster Lensing And Supernova survey with Hubble (CLASH) is a 524-orbit Multi-Cycle Treasury Program to use the gravitational lensing properties of 25 galaxy clusters to accurately constrain their mass distributions. The survey, described in detail in this paper, will definitively establish the degree of concentration of dark matter in the cluster cores, a key prediction of structure formation models. The CLASH cluster sample is larger and less biased than current samples of space-based imaging studies of clusters to similar depth, as we have minimized lensing-based selection that favors systems with overly dense cores. Specifically, 20 CLASH clusters are solely X-ray selected. The X-ray-selected clusters are massive (kT>5keV) and, in most cases, dynamically relaxed. Five additional clusters are included for their lensing strength ({theta}_Ein_>35" at z_s_=2) to optimize the likelihood of finding highly magnified high-z (z>7) galaxies. A total of 16 broadband filters, spanning the near-UV to near-IR, are employed for each 20-orbit campaign on each cluster. These data are used to measure precise ({sigma}_z_~0.02(1+z)) photometric redshifts for newly discovered arcs. Observations of each cluster are spread over eight epochs to enable a search for Type Ia supernovae at z>1 to improve constraints on the time dependence of the dark energy equation of state and the evolution of supernovae. We present newly re-derived X-ray luminosities, temperatures, and Fe abundances for the CLASH clusters as well as a representative source list for MACS1149.6+2223 (z=0.544).
- ID:
- ivo://CDS.VizieR/J/ApJS/224/33
- Title:
- CLASH-VLT: the FF cluster MACS J0416.1-2403
- Short Name:
- J/ApJS/224/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present VIMOS-Very Large Telescope (VLT) spectroscopy of the Frontier Fields (FF) cluster MACS J0416.1-2403 (z=0.397). Taken as part of the CLASH-VLT survey, the large spectroscopic campaign provided more than 4000 reliable redshifts over ~600arcmin^2^, including ~800 cluster member galaxies. The unprecedented sample of cluster members at this redshift allows us to perform a highly detailed dynamical and structural analysis of the cluster out to ~2.2r_200_ (~4Mpc). Our analysis of substructures reveals a complex system composed of a main massive cluster (M_200_~0.9x10^15^M_{sun}_ and {sigma}_V,r200_~1000km/s) presenting two major features: (i) a bimodal velocity distribution, showing two central peaks separated by {Delta}V_rf_~1100km/s with comparable galaxy content and velocity dispersion, and (ii) a projected elongation of the main substructures along the NE-SW direction, with a prominent sub-clump ~600kpc SW of the center and an isolated BCG approximately halfway between the center and the SW clump. We also detect a low-mass structure at z~0.390, ~10' south of the cluster center, projected at ~3Mpc, with a relative line-of-sight velocity of {Delta}V_rf_~-1700km/s. The cluster mass profile that we obtain through our dynamical analysis deviates significantly from the "universal" NFW, being best fit by a Softened Isothermal Sphere model instead. The mass profile measured from the galaxy dynamics is found to be in relatively good agreement with those obtained from strong and weak lensing, as well as with that from the X-rays, despite the clearly unrelaxed nature of the cluster. Our results reveal an overall complex dynamical state of this massive cluster and support the hypothesis that the two main subclusters are being observed in a pre-collisional phase, in agreement with recent findings from radio and deep X-ray data. In this article, we also release the entire redshift catalog of 4386 sources in the field of this cluster, which includes 60 identified Chandra X-ray sources and 105 JVLA radio sources.