- ID:
- ivo://CDS.VizieR/J/A+A/467/73
- Title:
- 3{sigma} hard sample of XMDS survey
- Short Name:
- J/A+A/467/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Our goal is to probe the populations of obscured and unobscured AGN investigating their optical-IR and X-ray properties as a function of X-ray flux, luminosity and redshift within a hard X-ray selected sample with wide multiwavelength coverage. We selected a sample of 136 X-ray sources detected at a significance of >=3{sigma} in the 2-10keV band (F_2-10_>~10^-14^erg/cm^2^/s) in a ~1deg^2^ area in the XMM Medium Deep Survey (XMDS, Cat. <J/A+A/439/413>). The XMDS area is covered with optical photometry from the VVDS and CFHTLS surveys and infrared Spitzer data from the SWIRE survey. Based on the X-ray luminosity and X-ray to optical ratio, 132 sources are likely AGN, of which 122 have unambiguous optical - IR identification. The observed optical and IR spectral energy distributions of all identified sources are fitted with AGN/galaxy templates in order to classify them and compute photometric redshifts. X-ray spectral analysis is performed individually for sources with a sufficient number of counts and using a stacking technique for subsamples of sources at different flux levels. Hardness ratios are used to estimate X-ray absorption in individual weak sources.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/830/14
- Title:
- SIGMA: Keck spectra of z~2 gal. in CANDELS fields
- Short Name:
- J/ApJ/830/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a survey of the internal kinematics of 49 star-forming galaxies at z~2 in the CANDELS fields with the Keck/MOSFIRE spectrograph, Survey in the near-Infrared of Galaxies with Multiple position Angles (SIGMA). Kinematics (rotation velocity V_rot_ and gas velocity dispersion {sigma}_g_) are measured from nebular emission lines which trace the hot ionized gas surrounding star-forming regions. We find that by z~2, massive star-forming galaxies (logM_*_/M_{sun}_>~10.2) have assembled primitive disks: their kinematics are dominated by rotation, they are consistent with a marginally stable disk model, and they form a Tully-Fisher relation. These massive galaxies have values of V_rot_/{sigma}_g_ that are factors of 2-5 lower than local well-ordered galaxies at similar masses. Such results are consistent with findings by other studies. We find that low-mass galaxies (logM_*_/M_{sun}_<~10.2) at this epoch are still in the early stages of disk assembly: their kinematics are often dominated by gas velocity dispersion and they fall from the Tully-Fisher relation to significantly low values of V_rot_. This "kinematic downsizing" implies that the process(es) responsible for disrupting disks at z~2 have a stronger effect and/or are more active in low-mass systems. In conclusion, we find that the period of rapid stellar mass growth at z~2 is coincident with the nascent assembly of low-mass disks and the assembly and settling of high-mass disks.
- ID:
- ivo://CDS.VizieR/J/ApJ/706/1364
- Title:
- SINS survey of high-redshift galaxies
- Short Name:
- J/ApJ/706/1364
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Spectroscopic Imaging survey in the near-infrared (near-IR) with SINFONI (SINS) of high-redshift galaxies. With 80 objects observed and 63 detected in at least one rest-frame optical nebular emission line, mainly H{alpha}, SINS represents the largest survey of spatially resolved gas kinematics, morphologies, and physical properties of star-forming galaxies at z~1-3. We describe the selection of the targets, the observations, and the data reduction. We then focus on the "SINS H{alpha} sample," consisting of 62 rest-UV/optically selected sources at 1.3<z<2.6 for which we targeted primarily the H{alpha} and [NII] emission lines. Only ~30% of this sample had previous near-IR spectroscopic observations. The galaxies were drawn from various imaging surveys with different photometric criteria; as a whole, the SINS H{alpha} sample covers a reasonable representation of massive M_*_>~10^10^M_{sun}_ star-forming galaxies at z~1.5-2.5, with some bias toward bluer systems compared to pure K-selected samples due to the requirement of secure optical redshift. The H{alpha} morphologies tend to be irregular and/or clumpy. About one-third of the SINS H{alpha} sample galaxies are rotation-dominated yet turbulent disks, another one-third comprises compact and velocity dispersion-dominated objects, and the remaining galaxies are clear interacting/merging systems; the fraction of rotation-dominated systems increases among the more massive part of the sample.
- ID:
- ivo://CDS.VizieR/J/PASJ/56/261
- Title:
- SiO maser survey in Galactic center
- Short Name:
- J/PASJ/56/261
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have surveyed ~400 known large-amplitude variables within 15' of the galactic center in the SiO J=1-0 v=1 and 2 maser lines at 43GHz, resulting in 180 detections. SiO lines were detected from 16 other sources located within 20" of the program objects. The detection rate of 48% is comparable to that in bulge IRAS surveys.
1545. SIRTF First-Look Survey
- ID:
- ivo://CDS.VizieR/J/AJ/125/2411
- Title:
- SIRTF First-Look Survey
- Short Name:
- J/AJ/125/2411
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The First-Look Survey (FLS) of the Space Infrared Telescope Facility (SIRTF) will cover about 5deg^2^ centered on J2000.0 (17:18+59:30) in order to characterize the extragalactic infrared sky 2 orders of magnitude deeper than the IRAS survey. We expect that most of the FLS far-infrared ({lambda} = 160, 70, and 24 {mu}m) sources will be star-forming galaxies obeying the very tight far-infrared/radio correlation and will be continuum radio sources with flux densities S>~100{mu}Jy at {nu}=1.4GHz. Conversely, radio sources stronger than 100{mu}Jy are usually powered by star-forming galaxies, plus some active galactic nuclei, and most should be detectable by the SIRTF FLS. Thus, a sensitive radio survey can be used to select and identify most of the SIRTF FLS source population before launch. We used the B configuration of the VLA to make an image of the FLS area at {nu}=1.4GHz with {sigma}=~23{mu}Jy/beam rms fluctuations, {theta}=5'' resolution, and {sigma}_{alpha}_=~{sigma}_{delta}_=~0.5'' rms uncertainties in right ascension and declination. The resulting radio image and catalog of 3565 radio components with peak flux densities Sp>=5{sigma}=115{mu}Jy/beam have been released via the Web to expedite follow-up optical identification and spectroscopy.
- ID:
- ivo://CDS.VizieR/J/AJ/136/580
- Title:
- Sixth VLBA calibrator survey: VCS6
- Short Name:
- J/AJ/136/580
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the sixth part of the Very Long Baseline Array (VLBA) Calibrator Survey. It contains the positions and maps of 264 sources of which 169 were not previously observed with very long baseline interferometry. This survey, based on two 24h VLBA observing sessions, was focused on (1) improving positions of 95 sources from previous VLBA Calibrator Surveys that were observed either with very large a priori position errors or were observed not long enough to get reliable positions and (2) observing remaining new flat-spectrum sources with predicted correlated flux density in the range 100-200mJy that were not observed in previous surveys. Source positions were derived from astrometric analysis of group delays determined at the 2.3 and 8.6GHz frequency bands using the Calc/Solve software package. The VCS6 catalog of source positions, plots of correlated flux density versus projected baseline length, contour plots and fits files of naturally weighted CLEAN images, as well as calibrated visibility function files, are available on the Web at http://vlbi.gsfc.nasa.gov/vcs6.
- ID:
- ivo://CDS.VizieR/J/A+A/622/A83
- Title:
- Sizes of infinity regions
- Short Name:
- J/A+A/622/A83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Backreactions from large-scale inhomogeneities may provide an elegant explanation for the observed accelerated expansion of the universe without the need to introduce dark energy. We propose a cosmological test for a specific model of inhomogeneous cosmology, called timescape cosmology. Using large-scale galaxy surveys such as SDSS and 2MRS, we test the variation of expansion expected in the {Lambda}-CDM model versus a more generic differential expansion using our own calibrations of bounds suggested by timescape cosmology. Our test measures the systematic variations of the Hubble flow towards distant galaxies groups as a function of the matter distribution in the lines of sight to those galaxy groups. We compare the observed systematic variation of the Hubble flow to mock catalogues from the Millennium Simulation in the case of the {Lambda}-CDM model, and a deformed version of the same simulation that exhibits more pronounced differential expansion. We perform a series of statistical tests, ranging from linear regressions to Kolmogorov-Smirnov tests, on the obtained data. They consistently yield results preferring {Lambda}-CDM cosmology over our approximated model of timescape cosmology. Our analysis of observational data shows no evidence that the variation of expansion differs from that of the standard {Lambda}-CDM model.
- ID:
- ivo://CDS.VizieR/J/ApJ/705/639
- Title:
- Sizes of Lyman alpha emitters at z=3.1
- Short Name:
- J/ApJ/705/639
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a rest-frame ultraviolet analysis of ~120 z~3.1 Lyman Alpha Emitters (LAEs) in the Extended Chandra Deep Field South. Using Hubble Space Telescope (HST) images taken as part of the Galaxy Evolution From Morphology and SEDS (GEMS) survey, Great Observatories Origins Deep Survey (GOODS), and Hubble Ultradeep Field surveys, we analyze the sizes of LAEs, as well as the spatial distribution of their components, which are defined as distinct clumps of UV-continuum emission. We set an upper limit of ~1kpc (~0.1") on the rms offset between the centroids of the continuum and Ly{alpha} emission. Most of the multi-component LAEs identified in shallow frames become connected in deeper images, suggesting that the majority of the rest-UV "clumps" are individual star-forming regions within a single system.
- ID:
- ivo://CDS.VizieR/V/105
- Title:
- SKY2000 Catalog, Version 3
- Short Name:
- V/105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The SKYMAP Star Catalog System consists of a Master Catalog stellar database and a collection of utility software designed to create and maintain the database and to generate derivative mission star catalogs (run catalogs). It contains an extensive compilation of information on almost 300000 stars brighter than 8.0 mag. The original SKYMAP Master Catalog was generated in the early 1970's. Incremental updates and corrections were made over the following years but the first complete revision of the source data occurred with Version 4.0. This revision also produced a unique, consolidated source of astrometric information which can be used by the astronomical community. The derived quantities were removed and wideband and photometric data in the R (red) and I (infrared) systems were added. Version 3 of the SKY2000 Master Catalog was completed in May of 2000 and represents an incremental but substantial improvement over Version 2 (Cat. <V/102>). A global replacement of photovisual (ptv) and photographic (ptg) magnitudes and of Henry Draper spectral types was performed using as sources the SAO Catalog, the PPM catalogs, and the HD catalogs. Several hundred entries previously lacking them now have CCD ST magnitudes from the star tracker onboard the SWAS spacecraft (transformed to the photometric system defined by the RXTE CCD ST data in SKY2000 Version 2). Several thousand missing HD catalog identifiers (mostly for HD Extension stars) were added, and several hundred missing variable star identifiers were added. 61 stars bright enough for inclusion in SKY2000 were added, bringing the total number of entries in the SKY2000 Version 3 Master Catalog to 299,160 (299,161 in Rev. 1).
- ID:
- ivo://CDS.VizieR/V/109
- Title:
- SKY2000 Catalog, Version 4
- Short Name:
- V/109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The SKYMAP Star Catalog System consists of a Master Catalog stellar database and a collection of utility software designed to create and maintain the database and to generate derivative mission star catalogs (run catalogs). It contains an extensive compilation of information on almost 300000 stars brighter than 8.0 mag. The original SKYMAP Master Catalog was generated in the early 1970's. Incremental updates and corrections were made over the following years but the first complete revision of the source data occurred with Version 4.0. This revision also produced a unique, consolidated source of astrometric information which can be used by the astronomical community. The derived quantities were removed and wideband and photometric data in the R (red) and I (infrared) systems were added. Version 4 of the SKY2000 Master Catalog was completed in April 2002; it marks the global replacement of the variability identifier and variability data fields. More details can be found in the description file sky2kv4.pdf. This version supersedes the previous versions 1(V/95), 2(V/102), and 3(V/105).
