- ID:
- ivo://CDS.VizieR/J/MNRAS/351/265
- Title:
- Cluster galaxy circular velocity function
- Short Name:
- J/MNRAS/351/265
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present galaxy circular velocity functions (GCVFs) for 34 low-redshift (z<~0.15) clusters identified in the Sloan Digital Sky Survey (SDSS, Cat. <J/AJ/123/567>), for 15 clusters drawn from dark matter simulations of hierarchical structure growth in a {LAMBDA}CDM cosmology, and for ~22000 SDSS field galaxies. We find that the simulations successfully reproduce the shape, amplitude and scatter in the observed distribution of cluster galaxy circular velocities. The power-law slope of the observed cluster GCVF is ~-2.4, independent of cluster velocity dispersion. The average slope of the simulated GCVFs is somewhat steeper, although formally consistent given the errors. We find that the effects of baryons on galaxy rotation curves is to flatten the simulated cluster GCVF into better agreement with observations. The cumulative GCVFs of the simulated clusters are very similar across a wide range of cluster masses, provided individual subhalo circular velocities are scaled by the circular velocities of the parent cluster. The scatter is consistent with that measured in the cumulative, scaled observed cluster GCVF. Finally, the observed field GCVF deviates significantly from a power law, being flatter than the cluster GCVF at circular velocities less than 200km/s.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/454/3816
- Title:
- Cobalt emission in nebular phase spectra
- Short Name:
- J/MNRAS/454/3816
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The light curves of Type Ia supernovae (SNe Ia) are powered by the radioactive decay of ^56^Ni to ^56^Co at early times, and the decay of ^56^Co to ^56^Fe from ~60 d after explosion. We examine the evolution of the [CoIII] {lambda}5893 emission complex during the nebular phase for SNe Ia with multiple nebular spectra and show that the line flux follows the square of the mass of ^56^Co as a function of time. This result indicates both efficient local energy deposition from positrons produced in ^56^Co decay and long-term stability of the ionization state of the nebula. We compile SN Ia nebular spectra from the literature and present 21 new late-phase spectra of 7 SNe Ia, including SN 2014J. From these we measure the flux in the [CoIII] {lambda}5893 line and remove its well-behaved time dependence to infer the initial mass of ^56^Ni (M_Ni_) produced in the explosion. We then examine ^56^Ni yields for different SN Ia ejected masses (M_ej_ - calculated using the relation between light-curve width and ejected mass) and find that the ^56^Ni masses of SNe Ia fall into two regimes: for narrow light curves (low stretch s~0.7-0.9), M_Ni_ is clustered near M_Ni_~0.4M_{sun}_ and shows a shallow increase as M_ej_ increases from ~1 to 1.4M_{sun}_; at high stretch, M_ej_ clusters at the Chandrasekhar mass (1.4M_{sun}_) while M_Ni_ spans a broad range from 0.6 to 1.2M_{sun}_. This could constitute evidence for two distinct SN Ia explosion mechanisms.
63. Cold galaxies
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/2050
- Title:
- Cold galaxies
- Short Name:
- J/MNRAS/453/2050
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use 350 {mu}m angular diameter estimates from Planck to test the idea that some galaxies contain exceptionally cold (10-13 K) dust, since colder dust implies a lower surface brightness radiation field illuminating the dust, and hence a greater physical extent for a given luminosity. The galaxies identified from their spectral energy distributions as containing cold dust do indeed show the expected larger 350 {mu}m diameters. For a few cold dust galaxies where Herschel data are available, we are able to use submillimetre maps or surface brightness profiles to locate the cold dust, which as expected generally lies outside the optical galaxy.
- ID:
- ivo://CDS.VizieR/J/AN/321/101
- Title:
- Compact groups of galaxies in LCRS
- Short Name:
- J/AN/321/101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have recently extracted a catalog of compact groups of galaxies (CGs) from the Las Campanas Redshift Survey. This catalog of Las Campanas Compact Groups (LCCGs) contains 76 CGs with a median redshift of z_med_~0.08. The physical properties of these CGs are similar to those form Hickson (1982, Cat. <VII/213>) and the Barton et al. (1996AJ....112..871B) catalogs. Here, we present an atlas of our catalog and briefly describe its general properties.
- ID:
- ivo://CDS.VizieR/J/MNRAS/418/1409
- Title:
- Compact groups of galaxies in SDSS DR7
- Short Name:
- J/MNRAS/418/1409
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the properties of photometrically selected compact groups (CGs) in the Sloan Digital Sky Survey. In this paper, the fourth in a series, we focus on understanding the characteristics of our observed CG sample with particular attention paid to quantifying and removing contamination from projected foreground or background galaxies. Based on a simple comparison of pairwise redshift likelihoods, we find that approximately half of CGs in the parent sample contain one or more projected (interloping) members; our final clean sample contains 4566 galaxies in 1086 CGs.
- ID:
- ivo://CDS.VizieR/J/other/RAA/19.29
- Title:
- Compilation of known QSOs for the Gaia mission
- Short Name:
- J/other/RAA/19.2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Quasars are essential for astrometric in the sense that they are spatial stationary because of their large distance from the Sun. The European Space Agency (ESA) space astrometric satellite Gaia is scanning the whole sky with unprecedented accuracy up to a few uas level. However, Gaia's two fields of view observations strategy may introduce a parallax bias in the Gaia catalog. Since it presents no significant parallax, quasar is perfect nature object to detect such bias. More importantly, quasars can be used to construct a Celestial Reference Frame in the optical wavelengths in Gaia mission. In this paper, we compile the most reliable quasars existing in literatures.The final compilation (designated as Known Quasars Catalog for Gaia mission, KQCG) contains 1842076 objects, among of them, 797632 objects are found in Gaia DR1 after cross-identifications. This catalog will be very useful in Gaia mission.
- ID:
- ivo://CDS.VizieR/J/MNRAS/468/1917
- Title:
- Concentration parameter of galaxy clusters
- Short Name:
- J/MNRAS/468/1917
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We characterized the population of galaxy clusters detected with the Sunyaev-Zeldovich (SZ) effect with Planck by measuring the cool-core state of the objects in a well-defined subsample of the Planck SZ catalogue. We used as an indicator the concentration parameter. The fraction of cool-core clusters is 29+/-4 per cent and does not show significant indications of evolution in the redshift range covered by our sample. We compare the distribution of the concentration parameter in the Planck sample with the one of the X-ray selected sample MACS: the distributions are significantly different and the cool-core fraction in MACS is much higher (59+/-5 per cent) than that in Planck. Since X-ray-selected samples are known to be biased towards cool cores due to the presence of their prominent surface brightness peak, we simulated the impact of the 'cool-core bias'. We found that this bias plays a large role in the difference between the fractions of cool cores in the two samples. We examined other selection effects that could in principle bias SZ surveys against cool cores, but we found that their impact is not sufficient to explain the difference between Planck and MACS. The population of X-ray underluminous objects, which are found in SZ surveys but missing in X-ray samples, could possibly contribute to the difference, as we found most of them to be non-cool cores, but this hypothesis deserves further investigation.
- ID:
- ivo://CDS.VizieR/J/MNRAS/465/2120
- Title:
- Correcting CIV-based virial black hole masses
- Short Name:
- J/MNRAS/465/2120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The CIV{lambda}{lambda}1498,1501 broad emission line is visible in optical spectra to redshifts exceeding z~5. CIV has long been known to exhibit significant displacements to the blue and these 'blueshifts' almost certainly signal the presence of strong outflows. As a consequence, single-epoch virial black hole (BH) mass estimates derived from CIV velocity widths are known to be systematically biased compared to masses from the hydrogen Balmer lines. Using a large sample of 230 high-luminosity (L_Bol_=10^45.5^-10^48^erg/s), redshift 1.5<z<4.0 quasars with both CIV and Balmer line spectra, we have quantified the bias in CIV BH masses as a function of the CIV blueshift. CIV BH masses are shown to be a factor of 5 larger than the corresponding Balmer-line masses at C IV blueshifts of 3000km/s and are overestimated by almost an order of magnitude at the most extreme blueshifts, ?=5000km/s. Using the monotonically increasing relationship between the CIV blueshift and the mass ratio BH(CIV)/BH(H{alpha}), we derive an empirical correction to all CIV BH masses. The scatter between the corrected CIV masses and the Balmer masses is 0.24dex at low CIV blueshifts (~0km/s) and just 0.10dex at high blueshifts (~3000km/s), compared to 0.40dex before the correction. The correction depends only on the CIV line properties - i.e. full width at half-maximum and blueshift - and can therefore be applied to all quasars where CIV emission line properties have been measured, enabling the derivation of unbiased virial BH-mass estimates for the majority of high-luminosity, high-redshift, spectroscopically confirmed quasars in the literature.
- ID:
- ivo://CDS.VizieR/J/MNRAS/427/3103
- Title:
- COSMOS field supermassive black holes
- Short Name:
- J/MNRAS/427/3103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the wide multiband photometry available in the Cosmic Evolution Survey (COSMOS) field, we explore the host galaxy properties of a large sample of active galactic nuclei (AGNs; ~1700 objects) with L_bol_ranging from 10^43^ to 10^47^erg/s, obtained by combining X-ray and optical spectroscopic selections. Based on a careful study of their spectral energy distributions, which have been parametrized using a two-component (AGN+galaxy) model fit, we have derived dust-corrected rest-frame magnitudes, colours and stellar masses of the obscured and unobscured AGN hosts up to high redshift (z<~3). Moreover, for the sample of obscured AGNs, we have also derived reliable star formation rates (SFRs). We find that AGN hosts span a large range of stellar masses and SFRs. No colour-bimodality is seen at any redshift in the AGN hosts, which are found to be mainly massive, red galaxies. Once we have accounted for the colour-mass degeneracy in well-defined mass-matched samples, we find a residual (marginal) enhancement of the incidence of AGNs in redder galaxies with lower specific SFRs. We argue that this result might emerge because of our ability to properly account for AGN light contamination and dust extinction, compared to surveys with a more limited multiwavelength coverage. However, because these colour shifts are relatively small, systematic effects could still be considered responsible for some of the observed trends. Interestingly, we find that the probability for a galaxy to host a black hole that is growing at any given `specific accretion rate' (i.e. the ratio of X-ray luminosity to the host stellar mass) is almost independent of the host galaxy mass, while it decreases as a power law with L_X_/M_*_. By analysing the normalization of such a probability distribution, we show how the incidence of AGNs increases with redshift as rapidly as (1 + {\em z})^4^, which closely resembles the overall evolution of the specific SFR of the entire galaxy population. We provide analytical fitting formulae that describe the probability of a galaxy of any mass (above the completeness limit of the COSMOS) to host an AGN of any given specific accretion rate as a function of redshift. These can be useful tools for theoretical studies of the growing population of black holes within galaxy evolution models. Although AGN activity and star formation in galaxies do appear to have a common triggering mechanism, at least in a statistical sense, within the COSMOS sample, we do not find any conclusive evidence to suggest that AGNs have a powerful influence on the star-forming properties of their host galaxies.
- ID:
- ivo://CDS.VizieR/J/PASP/97/932
- Title:
- 3CR Source Identifications
- Short Name:
- J/PASP/97/932
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains the third major update of new optical and radio data for the strong sources in the Revised Third Cambridge Catalogue (3CR). Positions, redshifts, magnitudes, and identifications are included, as well as some radio data for 298 3CR sources.
