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1091. FLAMES observations of NGC 5128's globular clusters
ID:
ivo://CDS.VizieR/J/ApJ/805/65
Title:
FLAMES observations of NGC 5128's globular clusters
Short Name:
J/ApJ/805/65
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a study of the dynamical properties of 125 compact stellar systems (CSSs) in the nearby giant elliptical galaxy NGC 5128, using high-resolution spectra (R~26000) obtained with Very Large Telescope/FLAMES. Our results provide evidence for a new type of star cluster, based on the CSS dynamical mass scaling relations. All radial velocity (v_r_) and line-of-sight velocity dispersion ({sigma}_los_) measurements are performed with the penalized pixel fitting (ppxf) technique, which provided {sigma}_ppxf_ estimates for 115 targets. The {sigma}_ppxf_ estimates are corrected to the 2D projected half-light radii, {sigma}_1/2_, as well as the cluster cores, {sigma}_0_, accounting for observational/aperture effects and are combined with structural parameters, from high spatial resolution imaging, in order to derive total dynamical masses (M_dyn_) for 112 members of NGC5128's star cluster system. In total, 89 CSSs have dynamical masses measured for the first time along with the corresponding dynamical mass-to-light ratios ({sigma}_1/2_). We find two distinct sequences in the {gamma}^dyn^_V_-M_dyn_ plane, which are well approximated by power laws of the forms {gamma}^dyn^_V_{propto}M_dyn_^0.33+/-0.04^ and {gamma}^dyn^_V_{propto}M_dyn_^0.79+/-0.04^. The shallower sequence corresponds to the very bright tail of the globular cluster luminosity function (GCLF), while the steeper relation appears to be populated by a distinct group of objects that require significant dark gravitating components such as central massive black holes and/or exotically concentrated dark matter distributions. This result would suggest that the formation and evolution of these CSSs are markedly different from the "classical" globular clusters in NGC 5128 and the Local Group, despite the fact that these clusters have luminosities similar to the GCLF turnover magnitude. We include a thorough discussion of myriad factors potentially influencing our measurements.
1092. Flat Galaxy Catalogue
ID:
ivo://CDS.VizieR/VII/162
Title:
Flat Galaxy Catalogue
Short Name:
VII/162
Date:
21 Oct 2021
Publisher:
CDS
Description:
A systematic search for disklike edge-on galaxies with a diameter larger than a=40 arcsec and major-to-minor axis ratio a/b>7 has been carried out by means of Palomar Observatory Sky Survey and ESO/SERC survey. As a result, we present new catalog of a flat galaxies (FGC) containing 4455 objects and covering about 56% of the whole sky for the first time. The catalog is assigned to study large-scale cosmic streamings and another problems of observational cosmology. Due to a better quality of the photographic emulsions used for the southern sky survey, the galaxies measured on ESO/SERC films extend to a surface magnitude slightly fainter than the same galaxies measured on POSS prints. So we present the catalog data separately for northern sky (DEC from -17.5 to +90 degrees) - FLAT GALAXY CATALOG , FGC, N = 2573 and for southern sky (DEC from -90 to -17.5 degrees) - SOUTHERN EXTENSION OF FLAT GALAXY CATALOG, FGCE, N = 1882. There are about 200 galaxies in a common region which were found and measured independently on POSS prints and ESO/SERC films. They were included in FGC, not in FGCE. The mean ratio <a(ESO)/a(POSS)> for them is equal to 1.26+/-0.4. This value is near to the result obtained by Lauberts (1982). Making some statistics it is easy to exclude FGCE galaxies with a <50arcsec to have the same depth of the sample. The Appendix to Flat Galaxy Catalog - Addendum - contains the data of 291 galaxies. They were selected in preliminary survey but rejected after more precise diameter measurements because of violation the a/b >= 7 criterion. In every case, these galaxies can be used in different observational programs.
1093. Flux- and volume-limited groups for SDSS galaxies
ID:
ivo://CDS.VizieR/J/A+A/566/A1
Title:
Flux- and volume-limited groups for SDSS galaxies
Short Name:
J/A+A/566/A1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We provide flux-limited and volume-limited galaxy group and cluster catalogues, based on the spectroscopic sample of the SDSS data release 10 galaxies. We used a modified friends-of-friends (FoF) method with a variable linking length in the transverse and radial directions to identify as many realistic groups as possible. The flux-limited catalogue incorporates galaxies down to m_r_=17.77mag. It includes 588193 galaxies and 82458 groups. The volume-limited catalogues are complete for absolute magnitudes down to M_r_= -18.0, -18.5, -19.0, -19.5, -20.0, -20.5, and -21.0; the completeness is achieved within different spatial volumes, respectively. Our analysis shows that flux-limited and volume-limited group samples are well compatible to each other, especially for the larger groups/clusters. Dynamical mass estimates, based on radial velocity dispersions and group extent in the sky, are added to the extracted groups. The catalogues can also be accessed via http://cosmodb.to.ee.
1094. Flux densities for 290 blazars
ID:
ivo://CDS.VizieR/J/AN/338/700
Title:
Flux densities for 290 blazars
Short Name:
J/AN/338/700
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of nine years of the blazar observing programme at the RATAN-600 radio telescope (2005-2014). The data were obtained at six frequency bands (1.1, 2.3, 4.8, 7.7, 11.2, 21.7GHz) for 290 blazars, mostly BL Lacs. In addition, we used data at 37GHz obtained quasi-simultaneously with the Metsahovi radio observatory for some sources. For each source NVSS name (RA (hhmmss) and DEC (ddmmss) for the J2000.0 epoch), and flux densities at seven frequencies are presented (1.1-37GHz).
1095. Fluxes in nearby star-forming galaxies
ID:
ivo://CDS.VizieR/J/ApJ/706/553
Title:
Fluxes in nearby star-forming galaxies
Short Name:
J/ApJ/706/553
Date:
21 Oct 2021
Publisher:
CDS
Description:
Compared to starburst galaxies, normal star-forming galaxies have been shown to display a much larger dispersion of the dust attenuation at fixed reddening through studies of the IRX-{beta} diagram (the IR/UV ratio "IRX" versus the UV color "{beta}"). To investigate the causes of this larger dispersion and attempt to isolate second parameters, we have used GALEX UV, ground-based optical, and Spitzer infrared imaging of eight nearby galaxies, and examined the properties of individual UV and 24um selected star-forming regions. We concentrated on star-forming regions, in order to isolate simpler star formation histories than those that characterize whole galaxies.
1096. Fluxes of NGG7793 & NGC4945 with GMOS-S
ID:
ivo://CDS.VizieR/J/ApJ/812/39
Title:
Fluxes of NGG7793 & NGC4945 with GMOS-S
Short Name:
J/ApJ/812/39
Date:
21 Oct 2021
Publisher:
CDS
Description:
Gas-phase abundances in HII regions of two spiral galaxies, NGC7793 and NGC4945, have been studied to determine their radial metallicity gradients. We used the strong-line method to derive oxygen abundances from spectra acquired with GMOS-S, the multi-object spectrograph on the 8m Gemini South telescope. We found that NGC7793 has a well-defined gas-phase radial oxygen gradient of -0.321+/-0.112dexR_25_^-1^ (or -0.054+/-0.019dex/kpc) in the galactocentric range 0.17<R_G_/R_25_<0.82, not dissimilar from gradients calculated with direct abundance methods in galaxies of similar mass and morphology. We also determined a shallow radial oxygen gradient in NGC 4945, -0.253+/-0.149dexR_25_^-1^ (or -0.019+/-0.011dex/kpc) for 0.04<R_G_/R_25_<0.51, where the larger relative uncertainty derives mostly from the larger inclination of this galaxy. NGC 7793 and NGC 4945 have been selected for this study because they are similar, in mass and morphology, to M33 and the Milky Way, respectively. Since at zeroth order we expect the radial metallicity gradients to depend on mass and galaxy type, we compared our galaxies in the framework of radial metallicity models best suited for M33 and the Galaxy. We found a good agreement between M33 and NGC7793, pointing toward similar evolution for the two galaxies. We notice instead differences between NGC 4945 and the radial metallicity gradient model that best fits the Milky Way. We found that these differences are likely related to the presence of an active galactic nucleus combined with a bar in the central regions of NGC 4945, and to its interacting environment.
1097. FMOS-COSMOS survey III. 0.7<z<2.5 galaxies
ID:
ivo://CDS.VizieR/J/ApJS/220/12
Title:
FMOS-COSMOS survey III. 0.7<z<2.5 galaxies
Short Name:
J/ApJS/220/12
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectroscopic survey of galaxies in the COSMOS field using the Fiber Multi-object Spectrograph (FMOS), a near-infrared instrument on the Subaru Telescope. Our survey is specifically designed to detect the H{alpha} emission line that falls within the H-band (1.6-1.8{mu}m) spectroscopic window from star-forming galaxies with 1.4<z<1.7 and M_stellar_>~10^10^M_{sun}_. With the high multiplex capability of FMOS, it is now feasible to construct samples of over 1000 galaxies having spectroscopic redshifts at epochs that were previously challenging. The high-resolution mode (R~2600) effectively separates H{alpha} and [NII]{lambda}6585, thus enabling studies of the gas-phase metallicity and photoionization state of the interstellar medium. The primary aim of our program is to establish how star formation depends on stellar mass and environment, both recognized as drivers of galaxy evolution at lower redshifts. In addition to the main galaxy sample, our target selection places priority on those detected in the far-infrared by Herschel/PACS to assess the level of obscured star formation and investigate, in detail, outliers from the star formation rate (SFR)--stellar mass relation. Galaxies with H{alpha} detections are followed up with FMOS observations at shorter wavelengths using the J-long (1.11-1.35{mu}m) grating to detect H{beta} and [OIII]{lambda}5008 which provides an assessment of the extinction required to measure SFRs not hampered by dust, and an indication of embedded active galactic nuclei. With 460 redshifts measured from 1153 spectra, we assess the performance of the instrument with respect to achieving our goals, discuss inherent biases in the sample, and detail the emission-line properties. Our higher-level data products, including catalogs and spectra, are available to the community.
1098. Follow-up spectroscopy of Ly{alpha} 3<z<7 emitters
ID:
ivo://CDS.VizieR/J/ApJ/815/57
Title:
Follow-up spectroscopy of Ly{alpha} 3<z<7 emitters
Short Name:
J/ApJ/815/57
Date:
21 Oct 2021
Publisher:
CDS
Description:
We explore the relationship between the spectral shape of the Ly{alpha} emission and the UV morphology of the host galaxy using a sample of 304 Ly{alpha}-emitting BVi-dropouts at 3<z<7 in the Great Observatories Origins Deep Survey and Cosmic Evolution Survey fields. Using our extensive reservoir of high-quality Keck DEIMOS spectra combined with Hubble Space Telescope WFC3 data, we measure the Ly{alpha} line asymmetries for individual galaxies and compare them to axial ratios measured from observed J- and H-band (restframe UV) images. We find that the Ly{alpha} skewness exhibits a large scatter at small elongation (a/b<2), and this scatter decreases as the axial ratio increases. Comparison of this trend to radiative transfer models and various results from the literature suggests that these high-redshift Ly{alpha} emitters are not likely to be intrinsically round and symmetric disks, but they probably host galactic outflows traced by Ly{alpha} emitting clouds. The ionizing sources are centrally located, and the optical depth is a good indicator of the absorption and scattering events on the escape path of Ly{alpha} photons from the source. Our results find no evidence of evolution in Ly{alpha} asymmetry or axial ratio with look-back time.
1099. Foreground galaxies toward FRB 190608 from SDSS
ID:
ivo://CDS.VizieR/J/ApJ/901/134
Title:
Foreground galaxies toward FRB 190608 from SDSS
Short Name:
J/ApJ/901/134
Date:
21 Feb 2022 09:50:38
Publisher:
CDS
Description:
Fast radio burst (FRB) 190608 was detected by the Australian Square Kilometre Array Pathfinder (ASKAP) and localized to a spiral galaxy at z_host_=0.11778 in the Sloan Digital Sky Survey (SDSS) footprint. The burst has a large dispersion measure (DM_FRB_=339.8pc/cm^3^) compared to the expected cosmic average at its redshift. It also has a large rotation measure (RM_FRB_=353rad/m^2^) and scattering timescale ({tau}=3.3ms at 1.28GHz). Chittidi+ (2021ApJ...922..173C) perform a detailed analysis of the ultraviolet and optical emission of the host galaxy and estimate the host DM contribution to be 110+/-37pc/cm^3^. This work complements theirs and reports the analysis of the optical data of galaxies in the foreground of FRB 190608 in order to explore their contributions to the FRB signal. Together, the two studies delineate an observationally driven, end-to-end study of matter distribution along an FRB sightline, the first study of its kind. Combining our Keck Cosmic Web Imager (KCWI) observations and public SDSS data, we estimate the expected cosmic dispersion measure DM_cosmic along the sightline to FRB 190608. We first estimate the contribution of hot, ionized gas in intervening virialized halos (DM_halos_~7-28pc/cm^3^). Then, using the Monte Carlo Physarum Machine methodology, we produce a 3D map of ionized gas in cosmic web filaments and compute the DM contribution from matter outside halos (DM_IGM_~91-126pc/cm^3^). This implies that a greater fraction of ionized gas along this sightline is extant outside virialized halos. We also investigate whether the intervening halos can account for the large FRB rotation measure and pulse width and conclude that it is implausible. Both the pulse broadening and the large Faraday rotation likely arise from the progenitor environment or the host galaxy.
1100. Formation of MW halo and its dwarf satellites
ID:
ivo://CDS.VizieR/J/A+A/604/A129
Title:
Formation of MW halo and its dwarf satellites
Short Name:
J/A+A/604/A129
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a homogeneous set of accurate atmospheric parameters for a complete sample of very and extremely metal-poor stars in the dwarf spheroidal galaxies (dSphs) Sculptor, Ursa Minor, Sextans, Fornax, Bootes I, Ursa Major II, and Leo IV. We also deliver a Milky Way (MW) comparison sample of giant stars covering the -4<[Fe/H]<-1.7 metallicity range. We show that, in the [Fe/H]=>-3.7 regime, the non-local thermodynamic equilibrium (NLTE) calculations with non-spectroscopic effective temperature (Teff) and surface gravity (log g) based on the photometric methods and known distance provide consistent abundances of the FeI and FeII lines. This justifies the FeI/FeII ionisation equilibrium method to determine log g for the MW halo giants with unknown distance. The atmospheric parameters of the dSphs and MW stars were checked with independent methods. In the [Fe/H]>-3.5 regime, the TiI/TiII ionisation equilibrium is fulfilled in the NLTE calculations. In the logg-Teff plane, all the stars sit on the giant branch of the evolutionary tracks corresponding to [Fe/H]=-2 to -4, in line with their metallicities. For some of the most metal-poor stars of our sample, we hardly achieve consistent NLTE abundances from the two ionisation stages for both iron and titanium. We suggest that this is a consequence of the uncertainty in the Teff-colour relation at those metallicities. The results of these work provide the base for a detailed abundance analysis presented in a companion paper.

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