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- ID:
- ivo://CDS.VizieR/J/A+A/446/773
- Title:
- GLMP sample of galactic OH/IR stars
- Short Name:
- J/A+A/446/773
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical and near-infrared finding charts taken from the DSS and 2MASS surveys of 94 IRAS sources selected from the GLMP catalogue, and accurate astrometry (~0.2") for most of them. Selection criteria were very red IRAS colours representative for OH/IR stars with optically thick circumstellar shells and the presence of variability according to the IRAS variability index (VAR>50). The main photometric properties of the stars in this `GLMP sample' are presented, discussed and compared with the correspondent properties of the `Arecibo sample' of OH/IR stars studied nearlier. We find that 37% of the sample (N=34) has no counterpart in the 2MASS, implying extremely high optical depths of their shells. Most of the sources identified in the 2MASS are faint (K>~8) and are of very red colour in the near-infrared, as expected. The brightest 2MASS counterpart (K=5.3mag) was found for IRAS18299-1705. Its blue colour H-K=1.3 suggests that IRAS18299-1705 is a post-AGB star. Few GLMP sources have faint but relatively blue counterparts. They might be misidentified field stars or stars that recently experienced a drop of their mass loss rates. The `GLMP sample' in general is made of oxygen-rich AGB stars, which are highly obscured by their circumstellar shells. They belong to the same population as the reddest OH/IR stars in the `Arecibo sample'.
- ID:
- ivo://CDS.VizieR/J/AJ/136/159
- Title:
- Global 86GHz VLBI survey of compact radio sources
- Short Name:
- J/AJ/136/159
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a large 86GHz global very long baseline interferometry (VLBI) survey of compact radio sources. The main goal of the survey is to increase by factors of 3-5 the total number of objects accessible for future 3mm VLBI imaging. The survey observations reach a baseline sensitivity of 0.1Jy and an image sensitivity of better than 10mJy/beam. A total of 127 compact radio sources have been observed. The observations have yielded images for 109 sources, extending the database of the sources imaged at 86GHz with VLBI observation by a factor of 5, and only six sources have not been detected. The remaining 12 objects have been detected but could not be imaged due to insufficient closure phase information.
- ID:
- ivo://CDS.VizieR/J/ApJ/793/92
- Title:
- Global properties of z=1~2 GMASS galaxies
- Short Name:
- J/ApJ/793/92
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on a study of the 2300-2600 {AA} Fe II/Fe II* multiplets in the rest-UV spectra of star-forming galaxies at 1.0<z<2.6 as probes of galactic-scale outflows. We extracted a mass-limited sample of 97 galaxies at z~1.0-2.6 from ultra-deep spectra obtained during the GMASS spectroscopic survey in the GOODS South field with the Very Large Telescope and FORS2. We obtain robust measures of the rest equivalent width of the Fe II absorption lines down to a limit of W_r_>1.5 {AA} and of the Fe II* emission lines to W_r_>0.5 {AA}. Whenever we can measure the systemic redshift of the galaxies from the [O II] emission line, we find that both the Fe II and Mg II absorption lines are blueshifted, indicating that both species trace gaseous outflows. We also find, however, that the Fe II gas has generally lower outflow velocity relative to that of Mg II. We investigate the variation of Fe II line profiles as a function of the radiative transfer properties of the lines, and find that transitions with higher oscillator strengths are more blueshifted in terms of both line centroids and line wings. We discuss the possibility that Fe II lines are suppressed by stellar absorptions. The lower velocities of the Fe II lines relative to the Mg II doublet, as well as the absence of spatially extended Fe II* emission in two-dimensional stacked spectra, suggest that most clouds responsible for Fe II absorption lie close (3~4 kpc) to the disks of galaxies. We show that the Fe II/Fe II* multiplets offer unique probes of the kinematic structure of galactic outflows.
- ID:
- ivo://CDS.VizieR/J/ApJ/696/785
- Title:
- Global SFR density over 0.7<z<1.9
- Short Name:
- J/ApJ/696/785
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We determine the global star formation rate (SFR) density at 0.7<z<1.9 using emission-line-selected galaxies identified in Hubble Space Telescope-Near Infrared Camera and Multi-Object Spectrograph (HST-NICMOS) grism spectroscopy observations. Observing in a pure parallel mode throughout HST Cycles 12 and 13, our survey covers ~104arcmin^2^ from which we select 80 galaxies with likely redshifted H{alpha} emission lines. In several cases, a somewhat weaker [OIII] doublet emission is also detected.
- ID:
- ivo://CDS.VizieR/J/AJ/151/7
- Title:
- Globular and open clusters observed by SDSS/SEGUE
- Short Name:
- J/AJ/151/7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present griz observations for the clusters M92, M13 and NGC 6791 and gr photometry for M71, Be 29 and NGC 7789. In addition we present new membership identifications for all these clusters, which have been observed spectroscopically as calibrators for the Sloan Digital Sky Survey (SDSS)/SEGUE survey; this paper focuses in particular on the red giant branch stars in the clusters. In a number of cases, these giants were too bright to be observed in the normal SDSS survey operations, and we describe the procedure used to obtain spectra for these stars. For M71, we also present a new variable reddening map and a new fiducial for the gr giant branch. For NGC 7789, we derived a transformation from T_eff_ to g-r for giants of near solar abundance, using IRFM T_eff_ measures of stars with good ugriz and 2MASS photometry and SEGUE spectra. The result of our analysis is a robust list of known cluster members with correctly dereddened and (if needed) transformed gr photometry for crucial calibration efforts for SDSS and SEGUE.
- ID:
- ivo://CDS.VizieR/J/ApJS/180/54
- Title:
- Globular cluster candidates in ACS Virgo survey.
- Short Name:
- J/ApJS/180/54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present catalogs of globular cluster candidates for the 100 galaxies of the Advanced Camera for Surveys Virgo Cluster Survey, a large program to carry out imaging of early-type members of the Virgo Cluster using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. We describe the procedure used to select bona fide globular cluster candidates out of the full list of detections based on model-based clustering methods with the use of expected contamination catalogs constructed using blank field observations and which are customized for each galaxy. We also present the catalogs of expected contaminants for each of our target galaxies. For each detected source we measure its position, magnitudes in the F475W (~Sloan g) and F850LP (~Sloan z) bandpasses, and half-light radii by fitting point-spread function convolved King models to the observed light distribution. These measurements are presented for 20375 sources, of which 12763 are likely to be globular clusters. Finally, we detail the calculation of the aperture corrections adopted for the globular cluster photometry.
- ID:
- ivo://CDS.VizieR/J/A+A/442/85
- Title:
- Globular cluster candidates in Low SB Galaxies
- Short Name:
- J/A+A/442/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Fifty-seven nearby low surface brightness dwarf galaxies (-10>~M_V_>~-16) were searched for globular cluster candidates (GCCs) using Hubble Space Telescope WFPC2 imaging in V and I. The sample consists of 18 dwarf spheroidal (dSph), 36 irregular (dIrr), and 3 "transition" type (dIrr/dSph) galaxies with angular sizes less than 3.7kpc situated at distances 2-6Mpc in the field and in the nearby groups: M 81, Centaurus A, Sculptor, Canes Venatici I cloud.
- ID:
- ivo://CDS.VizieR/J/AJ/148/32
- Title:
- Globular cluster candidates in NGC 3115
- Short Name:
- J/AJ/148/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Hubble Space Telescope/Advanced Camera for Surveys (HST/ACS) g and z photometry and half-light radii R_h_ measurements of 360 globular cluster (GC) candidates around the nearby S0 galaxy NGC 3115. We also include Subaru/Suprime-Cam g, r, and i photometry of 421 additional candidates. The well-established color bimodality of the GC system is obvious in the HST/ACS photometry. We find evidence for a "blue tilt" in the blue GC subpopulation, wherein the GCs in the blue subpopulation get redder as luminosity increases, indicative of a mass-metallicity relationship. We find a color gradient in both the red and blue subpopulations, with each group of clusters becoming bluer at larger distances from NGC 3115. The gradient is of similar strength in both subpopulations, but is monotonic and more significant for the blue clusters. On average, the blue clusters have ~10% larger R_h_than the red clusters. This average difference is less than is typically observed for early-type galaxies but does match that measured in the literature for the Sombrero Galaxy (M104), suggesting that morphology and inclination may affect the measured size difference between the red and blue clusters. However, the scatter on the R_h_ measurements is large. We also identify 31 clusters more extended than typical GCs, which we term ultra-compact dwarf (UCD) candidates. Many of these objects are actually considerably fainter than typical UCDs. While it is likely that a significant number will be background contaminants, six of these UCD candidates are spectroscopically confirmed as NGC 3115 members. To explore the prevalence of low-mass X-ray binaries in the GC system, we match our ACS and Suprime-Cam detections to corresponding Chandra X-ray sources. We identify 45 X-ray-GC matches: 16 among the blue subpopulation and 29 among the red subpopulation. These X-ray/GC coincidence fractions are larger than is typical for most GC systems, probably due to the increased depth of the X-ray data compared to previous studies of GC systems.
- ID:
- ivo://CDS.VizieR/J/ApJ/835/184
- Title:
- Globular cluster candidates in NGC4258
- Short Name:
- J/ApJ/835/184
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to explore the relationship between globular cluster total number, N_GC_, and central black hole mass, M_*_, in spiral galaxies, and compare it with that recently reported for ellipticals. We present results for the Sbc galaxy NGC 4258, from Canada-France-Hawaii Telescope data. Thanks to water masers with Keplerian rotation in a circumnuclear disk, NGC 4258 has the most precisely measured extragalactic distance and supermassive black hole mass to date. The globular cluster (GC) candidate selection is based on the (u*-i') versus (i'-Ks) diagram, which is a superb tool to distinguish GCs from foreground stars, background galaxies, and young stellar clusters, and hence can provide the best number counts of GCs from photometry alone, virtually free of contamination, even if the Galaxy is not completely edge-on. The mean optical and optical-near-infrared colors of the clusters are consistent with those of the Milky Way and M 31, after extinction is taken into account. We directly identify 39 GC candidates; after completeness correction, GC luminosity function extrapolation, and correction for spatial coverage, we calculate a total N_GC_=144+/-31_-36_^+38^ (random and systematic uncertainties, respectively). We have thus increased to six the sample of spiral galaxies with measurements of both M_*_ and N_GC_. NGC 4258 has a specific frequency S_N_=0.4+/-0.1 (random uncertainty), and is consistent within 2{sigma} with the N_GC_ versus M_*_ correlation followed by elliptical galaxies. The Milky Way continues to be the only spiral that deviates significantly from the relation.