- ID:
- ivo://CDS.VizieR/J/ApJ/693/152
- Title:
- Abell 851 and the role of starbursts
- Short Name:
- J/ApJ/693/152
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use extensive new observations of the very rich z~0.4 cluster of galaxies A851 (Cl 0939+47) to examine the nature and origin of starburst galaxies in intermediate-redshift clusters. New HST observations, 24um Spitzer photometry and ground-based spectroscopy cover most of a region of the cluster about 10' across, corresponding to a cluster-centric radial distance of about 1.6Mpc. This spatial coverage allows us to confirm the existence of a morphology-density relation within this cluster, and to identify several large, presumably infalling, subsystems. We confirm our previous conclusion that a very large fraction of the star-forming galaxies in A851 has recently undergone starbursts. We argue that starbursts are mostly confined to two kinds of sites: infalling groups and the cluster center.
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- ID:
- ivo://CDS.VizieR/J/ApJS/126/1
- Title:
- Abell clusters photometry
- Short Name:
- J/ApJS/126/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD photometry of 209 southern Abell clusters selected according to Bautz-Morgan type I, III, and II. We have performed total photometry in the Gunn r bandpass, classified stars and galaxies, and obtained structural parameters for the images. To estimate the photometric and structural errors on the CCD images and the completeness limits of our photometry, we performed realistic simulations of stars and galaxies and ran our classification algorithms. Here, we present central galaxy counts and metric photometry of the brightest cluster members, for which we give accurate positions, and compare this photometry with values in the literature. A linear magnitude-redshift relation has been derived from the tenth-ranked galaxy in each cluster. Photometric redshifts have been estimated for 57 clusters. We provide either spectroscopic or photometric redshifts for all the clusters in our sample. Further analysis of these data will be presented in further publications.
- ID:
- ivo://CDS.VizieR/J/AJ/118/1468
- Title:
- 35 Abell clusters Tully-Fisher observations
- Short Name:
- J/AJ/118/1468
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Tully-Fisher observations for 35 rich Abell clusters of galaxies. Results from I-band photometry and optical rotation curve work constitute the bulk of this paper. This is the third such data installment of an all-sky survey of 52 clusters in the distance range ~50 to 200h^-1^Mpc. The complete data set provides the basis for determining an accurate Tully-Fisher template relation and for estimating the amplitude and direction of the local bulk flow on a 100h^-1^Mpc scale
- ID:
- ivo://CDS.VizieR/J/A+A/607/A131
- Title:
- Abell 520 galaxies redshifts
- Short Name:
- J/A+A/607/A131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The mergers of galaxy clusters are the most energetic events in the universe after the Big Bang. An ever increasing fraction of local clusters exhibit signs of recent or past mergers. Our goal is to probe how these mergers affect the evolution and content of their member galaxies. We specifically aim to answer the following questions: Is the quenching of star formation in merging clusters enhanced when compared with relaxed clusters? Is the quenching accompanied by a (short lived) burst of star formation? We obtained optical spectroscopy of $>400$ galaxies in the field of the merging cluster Abell 520. We combine these observations with archival data to get a comprehensive picture of the state of star formation in the members of this merging cluster. Finally, we compare these observations with a control sample of 10 non-merging clusters at the same redshift from The Arizona Cluster Redshift Survey (ACReS). We split the member galaxies in passive, star forming or recently quenched depending on their spectra. The core of the merger shows a decreased fraction of star-forming galaxies compared to clusters in the non-merging sample. This region, dominated by passive galaxies, is extended along the axis of the merger. We find evidence of rapid quenching of the galaxies during the core passage with no signs of a star burst on the time scales of the merger. Additionally, we report the tentative discovery of an infalling group along the main filament feeding the merger, currently at ~2.5Mpc from the merger centre. This group contains a high fraction of star forming galaxies as well as ~2/3 of all the recently quenched galaxies in our survey.
- ID:
- ivo://CDS.VizieR/J/AJ/120/2338
- Title:
- Abell 576 redshifts
- Short Name:
- J/AJ/120/2338
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe observations of the nearby (cz=11487km/s) cluster of galaxies Abell 576 beyond the virial radius and into the infall region where galaxies are on their first or second pass through the cluster. Using 1057 redshifts, we use the infall pattern in redshift space to determine the mass profile of A576 to a radius of ~4h^-1^Mpc.
- ID:
- ivo://CDS.VizieR/J/A+A/602/A20
- Title:
- Abell 315 spectroscopic dataset
- Short Name:
- J/A+A/602/A20
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Determination of cluster masses is a fundamental tool for cosmology. Comparing mass estimates obtained by different probes allows to understand possible systematic uncertainties. Aims. The cluster Abell 315 is an interesting test case, since it has been claimed to be underluminous in X-ray for its mass (determined via kinematics and weak lensing). We have undertaken new spectroscopic observations with the aim of improving the cluster mass estimate, using the distribution of galaxies in projected phase space. We identified cluster members in our new spectroscopic sample. We estimated the cluster mass from the projected phase-space distribution of cluster members using the MAMPOSSt method. In doing this estimate we took into account the presence of substructures that we were able to identify. We identify several cluster substructures. The main two have an overlapping spatial distribution, suggesting a (past or ongoing) collision along the line-of-sight. After accounting for the presence of substructures, the mass estimate of Abell 315 from 14 kinematics is reduced by a factor 4, down to M_200_=0.8_-0.4_^+0.6^10+14M_{sun}_. We also find evidence that the cluster mass concentration is unusually low, c_200_=r_200_/r_-2_<1. Using our new estimate of c200 we revise the weak lensing mass estimate down to M_200_=1.8_-0.9_^+1.7^10+14M_{sun}_. Our new mass estimates are in agreement with that derived from the cluster X-ray luminosity via a scaling relation, M_200_=0.9+/-0.2*10^14^M_{sun}_. Abell 315 no longer belongs to the class of X-ray underluminous clusters. Its mass estimate was inflated by the presence of an undetected subcluster in collision with the main cluster. Whether the presence of undetected line-of-sight structures can be a general explanation for all X-ray underluminous clusters remains to be explored using a statistically significant sample.
- ID:
- ivo://CDS.VizieR/J/ApJ/425/418
- Title:
- Absolute R mag of brightest cluster galaxies
- Short Name:
- J/ApJ/425/418
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have measured the velocity of the Local Group with respect to an inertial frame defined by the 119 Abell and Abell, Corwin, & Olowin (ACO, Cat. <VII/110A>) clusters contained within 15000km/s. The observations consist of a full-sky peculiar velocity survey with an effective depth ranging from 8000 to 11000km/s, depending on how the observations are weighted with redshift. This is the deepest peculiar velocity survey yet conducted. Clusters are selected by heliocentric redshift, and the sample is volume-limited. We use the Hoessel (1980ApJ...241..493H) relationship between the metric luminosities of the brightest clusters galaxies (BCGs) and the slope of their brightness profiles as the distance indicator. The Cousins R-band luminosity within a metric radius of 10h^-1^kpc yields a typical distance error of 16% for a single BCG.
- ID:
- ivo://CDS.VizieR/J/ApJS/235/11
- Title:
- Absorption features in SDSS. I. MgII abs. doublets
- Short Name:
- J/ApJS/235/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the SDSS spectra of quasars included in the DR7Q or DR12Q catalogs, we search for MgII{lambda}{lambda}2796,2803 narrow absorption doublets in the spectra data around MgII{lambda}2798 emission lines. We obtain 17316 MgII doublets, within the redshift range of 0.3299<=z_abs_<=2.5663. We find that a velocity offset of {upsilon}_r_<6000km/s is a safe boundary to constrain the vast majority of associated Mg ii systems, although we find some doublets at {upsilon}_r_>6000km/s. If associated Mg ii absorbers are defined by {upsilon}_r_<6000km/s, ~33.3% of the absorbers are supposed to be contaminants of intervening systems. Removing the 33.3% contaminants, ~4.5% of the quasars present at least one associated MgII system with W_r_^{lambda}2796^>=0.2{AA}. The fraction of associated MgII systems with high-velocity outflows correlates with the average luminosities of their central quasars, indicating a relationship between outflows and the quasar feedback power. The {upsilon}_r_ distribution of the outflow MgII absorbers is peaked at 1023km/s, which is smaller than the corresponding value of the outflow CIV absorbers. The redshift number density evolution of absorbers (dn/dz) limited by {upsilon}_r_{>}-3000km/s differs from that of absorbers constrained by {upsilon}_r_>2000km/s. Absorbers limited by {upsilon}_r_>2000km/s and higher values exhibit profiles similar to dn/dz. In addition, the dn/dz is smaller when absorbers are constrained with larger {upsilon}_r_. The distributions of equivalent widths, and the ratio of W_r_^{lambda}2796^/W_r_^{lambda}2803^, are the same for associated and intervening systems, and independent of quasar luminosity.
- ID:
- ivo://CDS.VizieR/J/A+A/412/707
- Title:
- Absorption-line systems in QSO spectra - CoALS
- Short Name:
- J/A+A/412/707
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Absorption lines and absorption-line systems (ALSs) observed in the spectra of QSOs contain fundamental information on distribution of matter between the observer and the QSO, and on physical processes in the Universe in different epochs of the cosmological evolution. The presented catalog contains a compilation of basic information on absorption-line systems (ALSs) in QSO spectra. The data are taken from publications available to the authors up to January 2002. The catalog includes, in particular, all the data of the catalogs by Junkkarinen et al. (1991ApJS...77..203J) and York et al. (1991MNRAS.250...24Y ). The catalog consists of table1.dat, table2.txt and the list of references in refs.dat file. The present catalog is also available at the site of the Dept. of Theor. Astrophys. of the Ioffe Physical Technical Institute: <www.ioffe.ru/astro/QC>
- ID:
- ivo://CDS.VizieR/J/ApJ/845/85
- Title:
- Absorption velocities for 21 super-luminous SNe Ic
- Short Name:
- J/ApJ/845/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Super-luminous supernovae (SLSNe) are tremendously luminous explosions whose power sources and progenitors are highly debated. Broad-lined SNe Ic (SNe Ic-bl) are the only type of SNe that are connected with long-duration gamma-ray bursts (GRBs). Studying the spectral similarity and difference between the populations of hydrogen-poor SLSNe (SLSNe Ic) and of hydrogen-poor stripped-envelope core-collapse SNe, in particular SNe Ic and SNe Ic-bl, can provide crucial observations to test predictions of theories based on various power source models and progenitor models. In this paper, we collected all of the published optical spectra of 32 SLSNe Ic, 21 SNe Ic-bl, as well as 17 SNe Ic, quantified their spectral features, constructed average spectra, and compared them in a systematic way using new tools we have developed. We find that SLSNe Ic and SNe Ic-bl, including those connected with GRBs, have comparable widths for their spectral features and average absorption velocities at all phases. Thus, our findings strengthen the connection between SLSNe Ic and GRBs. In particular, SLSNe Ic have average FeII{lambda}5169 absorption velocities of -15000+/-2600km/s at 10 days after peak, which are higher than those of SNe Ic by ~7000km/s on average. SLSNe Ic also have significantly broader FeII{lambda}5169 lines than SNe Ic. Moreover, we find that such high absorption and width velocities of SLSNe Ic may be hard to explain with the interaction model, and none of the 13 SLSNe Ic with measured absorption velocities spanning over 10 days has a convincing flat velocity evolution, which is inconsistent with the magnetar model in one dimension. Lastly, we compare SN 2011kl, the first SN connected with an ultra-long GRB, with the mean spectrum of SLSNe Ic and of SNe Ic-bl.
