- ID:
- ivo://CDS.VizieR/J/ApJ/644/30
- Title:
- HST Observations of 2 high-z clusters
- Short Name:
- J/ApJ/644/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the photometric and structural properties of spectroscopically confirmed members in the two massive X-ray-selected z~0.83 galaxy clusters MS 105403 and RX J0152.7-1357 using three-band mosaic imaging with the Hubble Space Telescope Advanced Camera for Surveys. The samples include 105 and 140 members of RX J0152.7-1357 and MS 105403, respectively, to i_775_<24.0. A quantitative classification scheme using Sersic indices and "bumpiness" (the ratio of the rms residuals to the model mean) was found to correlate well with visual morphological type. The color-magnitude residuals correlate well with the local density, as measured from both galaxy numbers and weak lensing. Weaker correlations are found with cluster radius (the fundamental dependence is on local density).
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- ID:
- ivo://CDS.VizieR/J/ApJ/742/68
- Title:
- HST observations of low-mass BH host galaxies
- Short Name:
- J/ApJ/742/68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using Hubble Space Telescope observations of 147 host galaxies of low-mass black holes (BHs), we systematically study the structures and scaling relations of these active galaxies. Our sample is selected to have central BHs with virial masses of ~10^5^-10^6^M_{sun}_. The host galaxies have total I-band magnitudes of -23.2<M_I_<-18.8mag and bulge magnitudes of -22.9<M_I_<-16.1mag. Detailed bulge-disk-bar decompositions with GALFIT show that 93% of the galaxies have extended disks, 39% have bars, and 5% have no bulges at all at the limits of our observations. Based on the Sersic index and bulge-to-total ratio, we conclude that the majority of the galaxies with disks are likely to contain pseudobulges and very few of these low-mass BHs live in classical bulges. The fundamental plane of our sample is offset from classical bulges and ellipticals in a way that is consistent with the scaling relations of pseudobulges. The sample has smaller velocity dispersion at fixed luminosity in the Faber-Jackson plane compared with classical bulges and elliptical galaxies. The galaxies without disks are structurally more similar to spheroidals than to classical bulges according to their positions in the fundamental plane, especially the Faber-Jackson projection. Overall, we suggest that BHs with mass <~10^6^M_{sun}_ live in galaxies that have evolved secularly over the majority of their history. A classical bulge is not a prerequisite to host a BH.
- ID:
- ivo://CDS.VizieR/J/ApJS/177/148
- Title:
- HST survey of 3CR radio source counterparts. II.
- Short Name:
- J/ApJS/177/148
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the second part of an H-band (1.6um) "atlas" of z<0.3 3CR radio galaxies, using the Hubble Space Telescope Near Infrared Camera and Multi-Object Spectrometer (HST NICMOS2). We present new imaging for 21 recently acquired sources and host galaxy modeling for the full sample of 101 (including 11 archival) - an 87% completion rate. Two different modeling techniques are applied, following those adopted by the galaxy morphology and the quasar host galaxy communities. Results are compared and found to be in excellent agreement, although the former breaks down in the case of sources with strong active galactic nuclei (AGNs). Companion sources are tabulated, and the presence of mergers, tidal features, dust disks, and jets are cataloged. The tables form a catalog for those interested in the structural and morphological dust-free host galaxy properties of the 3CR sample, and for comparison with morphological studies of quiescent galaxies and quasar host galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A92
- Title:
- HydraI galaxy cluster dwarf catalog (HCDC)
- Short Name:
- J/A+A/659/A92
- Date:
- 10 Mar 2022 07:25:32
- Publisher:
- CDS
- Description:
- Due to their relatively low stellar mass content and diffuse nature, the evolution of dwarf galaxies can be strongly affected by their environment. Analyzing the properties of the dwarf galaxies over a wide range of luminosities, sizes, morphological types, and environments, we can obtain insights about their evolution. At ~50Mpc, the Hydra I cluster of galaxies is among the closest cluster in the z=~0 Universe, and an ideal environment to study dwarf galaxy properties in a cluster environment. We exploit deep imaging data of the Hydra I cluster to construct a new photometric catalog of dwarf galaxies in the cluster core, which is then used to derive properties of the Hydra I cluster dwarf galaxy population as well as to compare it with other clusters. Moreover, we investigate the dependency of dwarf galaxy properties on their surrounding environment. The new wide-field g- and r-band images of the Hydra I cluster obtained with the OmegaCAM camera on the VLT Survey Telescope (VST) in the context of the VST Early-type GAlaxy Survey (VEGAS) were used to study the dwarf galaxy population in the Hydra I cluster core down to r-band magnitude Mr=-11.5mag. We used an automatic detection tool to identify dwarf galaxies from a ~1deg^2^ field centered on the Hydra I core, covering almost half of the cluster virial radius. The photometric pipeline was used to estimate the principal photometric parameters for all targets. Scaling relations and visual inspection were used to assess the cluster membership and construct a new dwarf galaxy catalog. Finally, based on the new catalog, we studied the structural (Sersic index n, effective radius Re, and axis ratio) and photometric (colors and surface brightness) properties of the dwarf galaxies, also investigating how they vary as a function of clustercentric distance. The new Hydra I dwarf catalog contains 317 galaxies with a luminosity between -18.5<Mr<-11.5mag, a semi-major axis larger than ~200pc (a=0.84"), of which 202 are new detections, and previously unknown dwarf galaxies in the Hydra I central region. We estimate that our detection efficiency reaches 50% at the limiting magnitude Mr=-11.5mag, and at the mean effective surface brightness <{mu}_e,r_=26.5mag/arcsec^2^. We present the standard scaling relations for dwarf galaxies, which are color-magnitude, size-luminosity, and Sersic n-magnitude relations, and compare them with other nearby clusters. We find that there are no observational differences for dwarfs scaling relations in clusters of different sizes. We study the spatial distribution of galaxies, finding evidence for the presence of substructures within half the virial radius. We also find that mid- and high-luminosity dwarfs (Mr<-14.5mag) become, on average, redder toward the cluster center, and that they have a mild increase in Re with increasing clustercentric distance, similar to what is observed for the Fornax cluster. No clear clustercentric trends are reported for surface brightness and Sersic index. Considering galaxies in the same magnitude bins, we find that for high and mid-luminosity dwarfs (Mr<-13.5mag), the g-r color is redder for the brighter surface brightness and higher Sersic n index objects. This finding is consistent with the effects of harassment and/or partial gas stripping.
- ID:
- ivo://CDS.VizieR/J/AZh/94/1003
- Title:
- Infrared morphology of HII regions
- Short Name:
- J/AZh/94/1003
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A search for infrared ring nebulae associated with regions of ionized hydrogen has been carried out. The New GPS Very Large Array survey at 20 cm forms the basis of the search, together with observations obtained with the Spitzer Space Telescope at 8 and 24um and the Herschel Space Telescope at 70um. Objects having ring-like morphologies at 8um and displaying extended emission at 20cm were selected visually. Emission at 24um having the form of an inner ring or central peak is also observed in the selected objects. A catalog of 99 ring nebulae whose shapes at 8 and 70um are well approximated by ellipses has been compiled. The catalog contains 32 objects whose shapes are close to circular (eccentricities of the fitted ellipses at 8um no greater than 0.6, angular radius exceeding 20"). These objects are promising for comparisons with the results of one-dimensional hydrodynamical simulations of expanding regions of ionized hydrogen.
- ID:
- ivo://CDS.VizieR/J/A+A/616/A111
- Title:
- Integral-shaped filament NH_3_ observations
- Short Name:
- J/A+A/616/A111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent observations suggest a scenario in which filamentary structures in the interstellar medium represent the first step towards clumps/cores and eventually star formation. The densest filaments would then fragment into prestellar cores owing to gravitational instability. We seek to understand the roles filamentary structures play in high-mass star formation. We mapped the integral-shaped filament (ISF) located at the northern end of the Orion A molecular cloud in NH_3_ (1, 1) and (2, 2). The observations were made using the 25m radio telescope operated by the Xinjiang Astronomical Observatory, Chinese Academy of Sciences. The whole filamentary structure, about 1.2{deg}x0.6{deg}, is uniformly and fully sampled. We investigate the morphology, fragmentation, kinematics, and temperature properties in this region. We find that the morphology revealed by the map of velocity-integrated intensity of the NH_3_ (1, 1) line is closely associated with the dust ridge revealed by the Herschel Space Observatory. We identify 6 "lumps" related to the well known OMC-1 to 5 and 11 "sub-clumps" within the map. The clumps and sub-clumps are separated not randomly but in roughly equal intervals along the ISF. The average spacing of clumps is 11.30'+/-1.31' (1.36+/-0.16pc) and the average spacing of sub-clumps is 7.18'+/-1.19' (0.86+/-0.14pc). These spacings agree well with the predicted values of the thermal (0.86 pc) and turbulent sausage instability (1.43pc) by adopting a cylindric geometry of the ISF with an inclination of 60{deg} with respect to the line of sight. We also find a velocity gradient of about 0.6km/s/pc that runs along the ISF which likely arises from an overall rotation of the Orion A molecular cloud. The inferred ratio between rotational and gravitational energy is well below unity. Furthermore, fluctuations are seen in the centroid velocity diagram along the ISF. The OMC-1 to 5 clouds are located close to the local extrema of the fluctuations, which suggests that there exist gas flows associated with these clumps in the ISF. The derived NH_3_ (1, 1) and (2, 2) rotation temperatures in the OMC-1 are about 30-40K while lower temperatures (below 20K) are obtained in the northern and southern parts of the ISF. In OMC-2, OMC-3, and the northern part of OMC-4, we find higher and lower temperatures at the boundaries and in the interior, respectively.
- ID:
- ivo://CDS.VizieR/J/MNRAS/407/2475
- Title:
- Ionized gas in E/S0 galaxies with dust lanes
- Short Name:
- J/MNRAS/407/2475
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of multicolour observations of 30 E/S0 galaxies with dust lanes. For each galaxy we obtained broad-band images and narrow-band images using interference filters isolating the H{alpha}+[NII] emission lines to derive the amount and morphology of dust and ionized gas. To improve the wavelength coverage we retrieved data from the Sloan Digital Sky Survey and Two Micron All Sky Survey and combined these with our data. Ionized gas is detected in 25 galaxies and shows in most cases a smooth morphology, although knots and filamentary structure are also observed in some objects.
- ID:
- ivo://CDS.VizieR/J/AJ/116/2728
- Title:
- I photometry of early-type galaxies
- Short Name:
- J/AJ/116/2728
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of a project to compare the fundamental plane and Tully-Fisher distance scales, we present here I-band CCD photometry for 636 early-type galaxies in eight clusters and groups of galaxies. These are the A262, A1367, Coma (A1656), A2634, Cancer and Pegasus Clusters, and the NGC 383 and NGC 507 Groups. Sample selection, cluster properties, and cluster membership assignment criteria are discussed. We present photometric parameters that are used in the fundamental plane relation, the effective radius r_e_, and the effective surface brightness {mu}_e_, as derived from a r^1/4^ fit to the observed radial photometric profile of each galaxy. A comparison with similar data found in the literature for the Coma Cluster shows that large systematic uncertainties can be introduced in the measurement of r_e_ and {mu}_e_ by the particular method used to derive those parameters. However, the particular combination of these two parameters that enters in the fundamental plane relation is a quantity that can be measured with high accuracy.
- ID:
- ivo://CDS.VizieR/J/ApJ/727/1
- Title:
- IRAC/MUSYC SIMPLE survey
- Short Name:
- J/ApJ/727/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Spitzer IRAC/MUSYC Public Legacy Survey in the Extended CDF-South (SIMPLE), which consists of deep IRAC observations covering the ~1600arcmin^2^ area surrounding GOODS-S. The limiting magnitudes of the SIMPLE IRAC mosaics typically are 23.8, 23.6, 21.9, and 21.7, at 3.6um, 4.5um, 5.8um, and 8.0um, respectively (5{sigma} total point source magnitudes in AB). The SIMPLE IRAC images are combined with the 10'x15' GOODS IRAC mosaics in the center. We give detailed descriptions of the observations, data reduction, and properties of the final images, as well as the detection and photometry methods used to build a catalog. Using published optical and near-infrared data from the Multiwavelength Survey by Yale-Chile (MUSYC), we construct an IRAC-selected catalog, containing photometry in UBVRIz'JHK, [3.6um], [4.5um], [5.8um], and [8.0um]. The catalog contains 43,782 sources with S/N>5 at 3.6um, 19,993 of which have 13-band photometry. We compare this catalog to the publicly available MUSYC and FIREWORKS catalogs and discuss the differences. Using a high signal-to-noise sub-sample of 3391 sources with ([3.6]+[4.5])/2<21.2, we investigate the star formation rate history of massive galaxies out to z~1.8. We find that at z~1.8 at least 30+/-7% of the most massive galaxies (M*>10^11^M_{sun}_) are passively evolving, in agreement with earlier results from surveys covering less area.
- ID:
- ivo://CDS.VizieR/J/AJ/154/201
- Title:
- IR properties of stellar bowshock nebulae
- Short Name:
- J/AJ/154/201
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Arcuate infrared nebulae are ubiquitous throughout the Galactic Plane and are candidates for partial shells, bubbles, or bowshocks produced by massive runaway stars. We tabulate infrared photometry for 709 such objects using images from the Spitzer Space Telescope, the Wide-field Infrared Explorer, and the Herschel Space Observatory (HSO). Of the 709 objects identified at 24 or 22 {mu}m, 422 are detected at the HSO 70 {mu}m bandpass. Of these, only 39 are detected at HSO 160 {mu}m. The 70 {mu}m peak surface brightnesses are 0.5-2.5 Jyr/arcmin^2^. Color temperatures calculated from the 24 to 70 {mu}m ratios range from 80 to 400 K. Color temperatures from 70 to 160 {mu}m ratios are systematically lower, 40-200 K. Both of these temperature are, on average, 75% higher than the nominal temperatures derived by assuming that dust is in steady-state radiative equilibrium. This may be evidence of stellar wind bowshocks sweeping up and heating-possibly fragmenting but not destroying-interstellar dust. Infrared luminosity correlates with standoff distance, R_0_, as predicted by published hydrodynamical models. Infrared spectral energy distributions are consistent with interstellar dust exposed to either single radiant energy density, U=10^3^-10^5^ (in more than half of the objects) or a range of radiant energy densities U_min_=25 to U_max_=10^3^-10^5^ times the mean interstellar value for the remainder. Hence, the central OB stars dominate the energetics, making these enticing laboratories for testing dust models in constrained radiation environments. The spectral energy densities are consistent with polycyclic aromatic hydrocarbon fractions q_PAH_~<1% in most objects.
