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1091. Full spectroscopic data release of the SPT-GMOS
ID:
ivo://CDS.VizieR/J/ApJS/227/3
Title:
Full spectroscopic data release of the SPT-GMOS
Short Name:
J/ApJS/227/3
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500deg^2^ of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W, of [OII]{lambda}{lambda}3727, 3729 and H-{delta}, and the 4000{AA} break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m*). Finally, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ~20% of the full SPT-SZ sample.
1092. Full-Stokes polarimetry of 5 radio sources
ID:
ivo://CDS.VizieR/J/A+A/609/A68
Title:
Full-Stokes polarimetry of 5 radio sources
Short Name:
J/A+A/609/A68
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis pipeline that enables the recovery of reliable information for all four Stokes parameters with high accuracy. Its novelty relies on the effective treatment of the instrumental effects even before the computation of the Stokes parameters, contrary to conventionally used methods such as that based on the Mueller matrix. For instance, instrumental linear polarization is corrected across the whole telescope beam and significant Stokes Q and U can be recovered even when the recorded signals are severely corrupted by instrumental effects. The accuracy we reach in terms of polarization degree is of the order of 0.1-0.2%. The polarization angles are determined with an accuracy of almost 1{def}. The presented methodology was applied to recover the linear and circular polarization of around 150 active galactic nuclei, which were monitored between July 2010 and April 2016 with the Effelsberg 100-m telescope at 4.85GHz and 8.35GHz with a median cadence of 1.2 months. The polarized emission of the Moon was used to calibrate the polarization angle measurements. Our analysis showed a small system-induced rotation of about 1{deg} at both observing frequencies. Over the examined period, five sources have significant and stable linear polarization; three sources remain constantly linearly unpolarized; and a total of 11 sources have stable circular polarization degree m_c_, four of them with non-zero m_c_. We also identify eight sources that maintain a stable polarization angle. All this is provided to the community for future polarization observations reference. We finally show that our analysis method is conceptually different from those traditionally used and performs better than the Mueller matrix method. Although it has been developed for a system equipped with circularly polarized feeds, it can easily be generalized to systems with linearly polarized feeds as well.
1093. Fundamental manifold of spheroids
ID:
ivo://CDS.VizieR/J/ApJ/638/725
Title:
Fundamental manifold of spheroids
Short Name:
J/ApJ/638/725
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a unifying empirical description of the structural and kinematic properties of all spheroids embedded in dark matter halos. We find that the intracluster stellar spheroidal components of galaxy clusters, which we call cluster spheroids (CSphs) and which are typically 100 times the size of normal elliptical galaxies, lie on a fundamental plane as tight as that defined by elliptical galaxies (rms in effective radius of 0.07) but having a different slope.
1094. Fundamental Plane analysis in Shapley
ID:
ivo://CDS.VizieR/J/MNRAS/397/75
Title:
Fundamental Plane analysis in Shapley
Short Name:
J/MNRAS/397/75
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a Fundamental Plane (FP) analysis of 141 early-type galaxies in the Shapley supercluster at z=0.049 based on spectroscopy from the AAOmega spectrograph at the Anglo-Australian Telescope and photometry from the WFI on the European Southern Observatory/MPI 2.2-m telescope.
1095. Fundamental plane galaxies redshifts
ID:
ivo://CDS.VizieR/J/A+AS/140/327
Title:
Fundamental plane galaxies redshifts
Short Name:
J/A+AS/140/327
Date:
21 Oct 2021
Publisher:
CDS
Description:
Radial velocities and central velocity dispersions are derived for 238 E/S0 galaxies from medium-resolution spectroscopy. New spectroscopic data have been obtained as part of a study of the Fundamental Plane distances and peculiar motions of early-type galaxies in three selected directions of the South Equatorial Strip, undertaken in order to investigate the reality of large-scale streaming motion; results of this study have been reported in Mueller et al. (1998ApJ...507L.105M). The new APM South Equatorial Strip Catalog (-17.5deg<{delta}<+2.5deg) (Raychaudhury & Lynden-Bell, 2000) was used to select the sample of field galaxies in three directions: (1) 15h10-16h10; (2) 20h30-21h50; (3) 00h10-01h30. The spectra obtained have a median S/N per {AA} of 23, an instrumental resolution (FWHM) of ~4{AA}, and the spectrograph resolution (dispersion) is ~100km/s. The Fourier cross-correlation method was used to derive the radial velocities and velocity dispersions. The velocity dispersions have been corrected for the size of the aperture and for the galaxy effective radius. Comparisons of the derived radial velocities with data from the literature show that our values are accurate to 40km/s. A comparison with results from Jorgensen et al. (1995MNRAS.276.1341J) shows that the derived central velocity dispersion have an rms scatter of 0.036 in log{sigma}. There is no offset relative to the velocity dispersions of Davies et al. (1987ApJS...64..581D).
1096. Fundamental plane of early type galaxies
ID:
ivo://CDS.VizieR/J/A+A/309/749
Title:
Fundamental plane of early type galaxies
Short Name:
J/A+A/309/749
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyse the residuals to the fundamental plane (FP) of elliptical galaxies as a function of stellar-population indicators; these are based on the line-strength parameter Mg2 and on UBVRI broad-band colors, and are partly derived from new observations. The effect of the stellar populations accounts for approximately half the observed variation of the mass-to-light ratio responsible for the FP tilt. The residual tilt can be explained by the contribution of two additional effects: the dependence of the rotational support, and possibly that of the spatial structure, on the luminosity. We conclude to a constancy of the dynamical-to-stellar mass ratio. This probably extends to globular clusters as well, but the dominant factor would be here the luminosity dependence of the structure rather than that of the stellar population. This result also implies a constancy of the fraction of dark matter over all the scalelength covered by stellar systems. Our compilation of internal stellar kinematics of galaxies is appended.
1097. Fundamental planes of early-type galaxies
ID:
ivo://CDS.VizieR/J/ApJ/689/913
Title:
Fundamental planes of early-type galaxies
Short Name:
J/ApJ/689/913
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive the fundamental plane (FP) relation for a sample of 1430 early-type galaxies (ETGs) in the optical (r band) and the near-infrared (K band), by combining SDSS-DR5 and UKIDSS (UKIRT Infrared Deep Sky Survey, 2007MNRAS.379.1599L), second release data. With such a large, homogeneous data set, we are able to assess the dependence of the FP on the wave band. Our analysis indicates that the FP of luminous early-type galaxies is essentially wave band-independent, with its coefficients increasing at most by 8% from the optical to the NIR. This finding fits well into a consistent picture in which the tilt of the FP is not driven by stellar populations but results from other effects, such as nonhomology. In this framework, the optical and NIR FPs require more massive galaxies to be slightly more metal-rich than less massive ones, and to have highly synchronized ages, with an age variation per decade in mass smaller than a few percent.
1098. Fundamental stellar & halo data for local galaxies
ID:
ivo://CDS.VizieR/J/ApJ/859/2
Title:
Fundamental stellar & halo data for local galaxies
Short Name:
J/ApJ/859/2
Date:
21 Oct 2021
Publisher:
CDS
Description:
We build templates of rotation curves as a function of the I-band luminosity via the mass modeling (by the sum of a thin exponential disk and a cored halo profile) of suitably normalized, stacked data from wide samples of local spiral galaxies. We then exploit such templates to determine fundamental stellar and halo properties for a sample of about 550 local disk-dominated galaxies with high-quality measurements of the optical radius R_opt_ and of the corresponding rotation velocity V_opt_. Specifically, we determine the stellar M_*_ and halo M_H_ masses, the halo size R_H_ and velocity scale V_H_, and the specific angular momenta of the stellar j_*_ and dark matter j_H_ components. We derive global scaling relationships involving such stellar and halo properties both for the individual galaxies in our sample and for their mean within bins; the latter are found to be in pleasing agreement with previous determinations by independent methods (e.g., abundance matching techniques, weak-lensing observations, and individual rotation curve modeling). Remarkably, the size of our sample and the robustness of our statistical approach allow us to attain an unprecedented level of precision over an extended range of mass and velocity scales, with 1{sigma} dispersion around the mean relationships of less than 0.1dex. We thus set new standard local relationships that must be reproduced by detailed physical models, which offer a basis for improving the subgrid recipes in numerical simulations, that provide a benchmark to gauge independent observations and check for systematics, and that constitute a basic step toward the future exploitation of the spiral galaxy population as a cosmological probe.
1099. FUV and NUV magnitudes of ETG
ID:
ivo://CDS.VizieR/J/MNRAS/446/2030
Title:
FUV and NUV magnitudes of ETG
Short Name:
J/MNRAS/446/2030
Date:
21 Oct 2021
Publisher:
CDS
Description:
We extend our initial study of the connection between the UV colour of galaxies and both the inferred stellar mass-to-light ratio, {Upsilon}*, and a mass-to-light ratio referenced to Salpeter initial mass function (IMF) models of the same age and metallicity, {Upsilon}*/{Upsilon}_Sal_, using new UV magnitude measurements for a much larger sample of early-type galaxies, ETGs, with dynamically determined mass-to-light ratios. We confirm the principal empirical finding of our first study, a strong correlation between the GALEX FUV-NUV colour and {Upsilon}*. We show that this finding is not the result of spectral distortions limited to a single passband (e.g. metallicity-dependent line-blanketing in the NUV band), or of the analysis methodology used to measure {Upsilon}*, or of the inclusion or exclusion of the correction for stellar population effects as accounted for using {Upsilon}*/{Upsilon}_Sal_. The sense of the correlation is that galaxies with larger {Upsilon}*, or larger {Upsilon}*/{Upsilon}_Sal_, are bluer in the UV. We conjecture that differences in the low-mass end of the stellar IMF are related to the nature of the extreme horizontal branch stars generally responsible for the UV flux in ETGs. If so, then UV colour can be used to identify ETGs with particular IMF properties and to estimate {Upsilon}*. We also demonstrate that UV colour can be used to decrease the scatter about the Fundamental Plane and Manifold, and to select peculiar galaxies for follow-up with which to further explore the cause of variations in {Upsilon}* and UV colour.
1100. FUV excess in early-type galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/414/3410
Title:
FUV excess in early-type galaxies
Short Name:
J/MNRAS/414/3410
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present surface photometry of a sample of 52 galaxies from the GALaxy Evolution eXplorer (GALEX) and Two-Micron All-Sky Survey (2MASS) data archives. These include 32 normal elliptical galaxies, 10 ellipticals with weak LINER or other nuclear activity and 10 star-forming ellipticals or early-type spirals. We examine the spatial distribution of the far-ultraviolet excess in these galaxies, and its correlation with dynamical and stellar population properties of the galaxies.