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631. SAMI Galaxy Survey: gas streaming
ID:
ivo://CDS.VizieR/J/MNRAS/456/1299
Title:
SAMI Galaxy Survey: gas streaming
Short Name:
J/MNRAS/456/1299
Date:
21 Oct 2021
Publisher:
CDS
Description:
Line-of-sight velocities of gas and stars can constrain dark matter (DM) within rotationally supported galaxies if they trace circular orbits extensively. Photometric asymmetries may signify non-circular motions, requiring spectra with dense spatial coverage. Our integral-field spectroscopy of 178 galaxies spanned the mass range of the Sydney-AAO Multi-object integral field spectrograph (SAMI) Galaxy Survey. We derived circular speed curves (CSCs) of gas and stars from non-parametric fits out to r~2re. For 12/14 with measured HI profiles, ionized gas and HI maximum velocities agreed. We fitted mass-follows-light models to 163 galaxies by approximating the radial light profile as nested, very flattened mass homeoids viewed as a Sersic form. Fitting broad-band spectral energy distributions to Sloan Digital Sky Survey images gave median stellar mass/light 1.7 assuming a Kroupa initial mass function (IMF) versus 2.6 dynamically. Two-thirds of the dynamical mass/light measures were consistent with star+remnant IMFs. One-fifth required upscaled starlight to fit, hence comparable mass of unobserved baryons and/or DM distributed like starlight across the SAMI aperture that came to dominate motions as the starlight CSCs declined rapidly. The rest had mass distributed differently from light. Subtracting fits of Sersic radial profiles to 13 VIKING Z-band images revealed residual weak bars. Near the bar major axis, we assessed m=2 streaming velocities, and found deviations usually <30km/s from the CSC; three showed no deviation. Thus, asymmetries rarely influenced the CSC despite colocated shock-indicating, emission-line flux ratios in more than 2/3 of our sample.
632. SAMI Pilot Survey
ID:
ivo://CDS.VizieR/J/MNRAS/454/2050
Title:
SAMI Pilot Survey
Short Name:
J/MNRAS/454/2050
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the SAMI Pilot Survey, consisting of integral field spectroscopy of 106 galaxies across three galaxy clusters, Abell 85, Abell 168 and Abell 2399. The galaxies were selected by absolute magnitude to have Mr<-20.25mag. The survey, using the Sydney-AAO Multi-object Integral field spectrograph (SAMI), comprises observations of galaxies of all morphological types with 75 per cent of the sample being early-type galaxies (ETGs) and 25 per cent being late-type galaxies (LTGs). Stellar velocity and velocity dispersion maps are derived for all 106 galaxies in the sample. The {lambda}_R_ parameter, a proxy for the specific stellar angular momentum, is calculated for each galaxy in the sample. We find a trend between {lambda}_R_ and galaxy concentration such that LTGs are less concentrated higher angular momentum systems, with the fast-rotating ETGs (FRs) more concentrated and lower in angular momentum. This suggests that some dynamical processes are involved in transforming LTGs to FRs, though a significant overlap between the {lambda}_R_ distributions of these classes of galaxies implies that this is just one piece of a more complicated picture. We measure the kinematic misalignment angle, {Psi}, for the ETGs in the sample, to probe the intrinsic shapes of the galaxies. We find the majority of FRs (83 per cent) to be aligned, consistent with them being oblate spheroids (i.e. discs). The slow rotating ETGs (SRs), on the other hand, are significantly more likely to show kinematic misalignment (only 38 per cent are aligned). This confirms previous results that SRs are likely to be mildly triaxial systems.
633. Sample of galaxies near South Celestial Pole
ID:
ivo://CDS.VizieR/J/MNRAS/366/267
Title:
Sample of galaxies near South Celestial Pole
Short Name:
J/MNRAS/366/267
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper reports the results of a modest redshift survey carried out, at generally low Galactic latitudes, in the vicinity of the South Celestial Pole. Target galaxies were selected as a 'representative' sample of underlying large-scale structures. Dimensions, approximate magnitudes and radial velocity measurements, are reported for 335 galaxies.
634. Sample of GOODS/CDFS early-type galaxies
ID:
ivo://CDS.VizieR/J/ApJ/635/243
Title:
Sample of GOODS/CDFS early-type galaxies
Short Name:
J/ApJ/635/243
Date:
21 Oct 2021
Publisher:
CDS
Description:
We explore the evolution of field early-type galaxies in a sample extracted from the ACS images of the southern GOODS field. The galaxies are selected by means of a nonparametric analysis, followed by visual inspection of the candidates with a concentrated surface brightness distribution. We furthermore exclude from the final sample those galaxies that are not consistent with an evolution into the Kormendy relation between surface brightness and size that is observed for z=0 ellipticals. The final set, which comprises 249 galaxies with a median redshift z_m_=0.71, represents a sample of early-type systems not selected with respect to color, with similar scaling relations as those of bona fide elliptical galaxies.
635. Sample of major galaxy pairs at z=0.08-0.38
ID:
ivo://CDS.VizieR/J/AJ/139/1857
Title:
Sample of major galaxy pairs at z=0.08-0.38
Short Name:
J/AJ/139/1857
Date:
21 Oct 2021
Publisher:
CDS
Description:
We measure the strength, frequency, and timescale of tidally triggered star formation at redshift z=0.08-0.38 in a spectroscopically complete sample of galaxy pairs drawn from the magnitude-limited redshift survey of 9825 Smithsonian Hectospec Lensing Survey galaxies with R<20.3. To examine the evidence for tidal triggering, we identify a volume-limited sample of major (|{Delta}M_R_|<1.75, corresponding to mass ratio >1/5) pair galaxies with M_R_<-20.8 in the redshift range z=0.08-0.31.
636. Sample of MaNGA galaxies properties
ID:
ivo://CDS.VizieR/J/A+A/623/A122
Title:
Sample of MaNGA galaxies properties
Short Name:
J/A+A/623/A122
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive rotation curves, surface brightness profiles, and oxygen abundance distributions for 147 late-type galaxies using the publicly available spectroscopy obtained by the MaNGA survey. Changes of the central oxygen abundance (O/H)_0_, the abundance at the optical radius (O/H)_R25_, and the abundance gradient with rotation velocity V_rot_ were examined for galaxies with rotation velocities from 90km/s to 350km/s. We find that each relation shows a break at V_rot_^*^~200km/s. The central (O/H)_0_ abundance increases with rising V_rot_ and the slope of the (O/H)_0_-V_rot_ relation is steeper for galaxies with V_rot_<=V_rot_^*^. The mean scatter of the central abundances around this relation is 0.053 dex. The relation between the abundance at the optical radius of a galaxy and its rotation velocity is similar; the mean scatter in abundances around this relation is 0.081 dex. The radial abundance gradient expressed in dex/kpc flattens with the increase of the rotation velocity. The slope of the relation is very low for galaxies with V_rot_>=V_rot_^*^. The abundance gradient expressed in dex/R_25_ is roughly constant for galaxies with V_rot_<=V_rot_^*^, flattens towards V_rot_^*^, and then again is roughly constant for galaxies with V_rot_>=V_rot_^*^. The change of the gradient expressed in terms of dex/h_d_ (where h_d_ is the disc scale length), in terms of dex/R_e,d_ (where R_e,d_ is the disc effective radius), and in terms of dex/R_e,g_ (where R_e,g_ is the galaxy effective radius) with rotation velocity is similar to that for gradient in dex/R_25_. The relations between abundance characteristics and other basic parameters (stellar mass, luminosity, and radius) are also considered.
637. San Fernando AC Zone Data Reduced to ACRS
ID:
ivo://CDS.VizieR/I/222
Title:
San Fernando AC Zone Data Reduced to ACRS
Short Name:
I/222
Date:
21 Oct 2021
Publisher:
CDS
Description:
The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the San Fernando Zone, whose plates are centered between declinations -3 and -9 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 225,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
638. Santiago catalogue of 1105 FK5 stars
ID:
ivo://CDS.VizieR/J/A+AS/95/355
Title:
Santiago catalogue of 1105 FK5 stars
Short Name:
J/A+AS/95/355
Date:
21 Oct 2021
Publisher:
CDS
Description:
The positions in right ascension and declination of 1105 FK5 stars, observed with a Meridian Circle during the period 1979 to 1991, are given. The average mean square error of a position, for the whole catalog, is +/-0.009s in right ascension and +/-0.10arcsec in declination. The mean epoch of the catalog is 1983.148.
639. SBS/Zwicky cluster relation
ID:
ivo://CDS.VizieR/VII/251
Title:
SBS/Zwicky cluster relation
Short Name:
VII/251
Date:
21 Oct 2021
Publisher:
CDS
Description:
In the same area covered by Second Byurakan Survey and CGCG, there are 1677 SBS galaxies, of which 892 are positioned inside the contours of Zwicky clusters. Data on these galaxies and respective clusters are presented in different tables, according to whether they are galaxies which are members of clusters or their substructures, probable or possible members. Projection cases are considered separately.
640. SC4K catalogue of candidate LAEs
ID:
ivo://CDS.VizieR/J/MNRAS/476/4725
Title:
SC4K catalogue of candidate LAEs
Short Name:
J/MNRAS/476/4725
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present and explore deep narrow- and medium-band data obtained with the Subaru and the Isaac Newton Telescopes in the ~2deg^2^ COSMOS field. We use these data as an extremely wide, low-resolution (R~20-80) Integral Field Unit survey to slice through the COSMOS field and obtain a large sample of ~4000 Ly{alpha} emitters (LAEs) from z~2 to 6 in 16 redshift slices (SC4K). We present new Ly {alpha} luminosity functions (LFs) covering a comoving volume of ~10^8^Mpc^3^. SC4K extensively complements ultradeep surveys, jointly covering over 4dex in Ly{alpha} luminosity and revealing a global (2.5<z<6) synergy LF with {alpha}=-1.93^+0.12^_-0.12_, log_10_{Phi}^*^_Ly{alpha}_=-3.45^+0.22^_-0.29_Mpc^-3^, and log_10_L^*^_Ly{alpha}_=42.93^+0.15^_-0.11_erg/s. The Schechter component of the Ly{alpha} LF reveals a factor ~5 rise in L^*^_Ly{alpha}_ and a ~7 x decline in {Phi}^*^_Ly{alpha}_ from z~2 to 6. The data reveal an extra power-law (or Schechter) component above L_Ly{alpha}_~=10^43.3^erg/s at z~2.2-3.5 and we show that it is partially driven by X-ray and radio active galactic nucleus (AGN), as their Ly{alpha} LF resembles the excess. The power-law component vanishes and/or is below our detection limits above z>3.5, likely linked with the evolution of the AGN population. The Ly {alpha} luminosity density rises by a factor ~2 from z~2 to 3 but is then found to be roughly constant (1.1^+0.2^_-0.2_x10^40^erg/s/Mpc^3^) to z~6, despite the ~0.7 dex drop in ultraviolet (UV) luminosity density. The Ly{alpha}/UV luminosity density ratio rises from 4+/-1 per cent to 30+/-6 per cent from z~2.2 to 6. Our results imply a rise of a factor of ~=2 in the global ionization efficiency ({xi}_ion_) and a factor ~=4+/-1 in the Ly{alpha} escape fraction from z~2 to 6, hinting for evolution in both the typical burstiness/stellar populations and even more so in the typical interstellar medium conditions allowing Ly{alpha} photons to escape.

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