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1501. High frequency peakers. The faint sample
ID:
ivo://CDS.VizieR/J/AN/330/223
Title:
High frequency peakers. The faint sample
Short Name:
J/AN/330/223
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a sample of sources with convex radio spectra peaking at frequencies above a few GHz, known as "High Frequency Peakers" (HFPs). A "bright" sample with a flux density limit of 300mJy at 5GHz has been presented by Dallacasa et al. (2000, Cat. J/A+A/363/887). Here we present the "faint" sample with flux density between 50 and 300mJy at 5GHz, restricted to the area around the North Galactic Cap, where the FIRST catalogue is available. The candidates have been observed with the VLA at several frequencies ranging from 1.4 to 22GHz, in order to derive a simultaneous radio spectrum. The final list of confirmed HFP sources consists of 61 objects.
1502. High-redshift candidate Herschel sources
ID:
ivo://CDS.VizieR/J/A+A/622/A106
Title:
High-redshift candidate Herschel sources
Short Name:
J/A+A/622/A106
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new catalog of high-redshift candidate Herschel sources. Our sample is obtained after applying a multifrequency filtering method (matched multifilter), which is designed to improve the signal-to-noise ratio (SNR) of faint extragalactic point sources. The method is tested against already-detected sources from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) and used to search for new high-redshift candidates. The multifilter technique produces also an estimation of the photometric redshift of the sources. When compared with a sample of sources with known spectroscopic redshift, the photometric redshift returned from the multifilter is unbiased in the redshift range 0.8<z<4.3. Using simulated data we reproduce the same unbiased result in roughly the same redshift range and determined the error (and bias above z=4) in the photometric redshifts. Based on the multifilter technique, and a selection based on color, flux, and agreement of fit between the observed photometry and assumed SED, we find 370 robust candidates to be relatively bright high-redshift sources. A second sample with 237 objects focuses on the faint end at high-redshift. These 237 sources were previously near the H-ATLAS detection limit but are now confirmed with our technique as high significance detections. Finally, we look for possible lensed Herschel sources by cross-correlating the first sample of 370 objects with two different catalogs of known low-redshift objects, the redMaPPer Galaxy Cluster Catalog and a catalog of galaxies with spectroscopic redshift from the Sloan Digital Sky Survey Data Release 14. Our search renders a number of candidates to be lensed systems from the SDSS cross-correlation but none from the redMaPPeR confirming the more likely galactic nature of the lenses.
1503. High-redshift Ly{alpha} emitters
ID:
ivo://CDS.VizieR/J/ApJ/725/394
Title:
High-redshift Ly{alpha} emitters
Short Name:
J/ApJ/725/394
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an atlas of 88 z~5.7 and 30 z~6.5 Ly{alpha} emitters obtained from a wide-field narrowband survey. We combined deep narrowband imaging in 120{AA} bandpass filters centered at 8150{AA} and 9140{AA} with deep BVRIz broadband imaging to select high-redshift galaxy candidates over an area of 4180arcmin^2^. The goal was to obtain a uniform selection of comparable depth over the seven targeted fields in the two filters. For the GOODS-North region of the Hubble Deep Field-North field, we also selected candidates using a 120{AA} filter centered at 9210{AA}. We made spectroscopic observations with Keck DEIMOS of nearly all the candidates to obtain the final sample of Ly{alpha} emitters. At the 3.3{AA} resolution of the DEIMOS observations the asymmetric profile for Ly{alpha} emission can be clearly seen in the spectra of nearly all the galaxies. We show that the spectral profiles are surprisingly similar for many of the galaxies and that the composite spectral profiles are nearly identical at z=5.7 and z=6.5.
1504. High-redshift molecular outflow
ID:
ivo://CDS.VizieR/J/A+A/632/L7
Title:
High-redshift molecular outflow
Short Name:
J/A+A/632/L7
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of a high-redshift, massive molecular outflow in the starburst galaxy SPT 0346-52 (z=5.656) via the detected absorption of high-excitation water transitions (H_2_O 4_2,3_-4_1,4_ and H_2_O 3_3,0_-3_2,1_) with the Atacama Large Millimeter/submillimeter Array (ALMA). The host galaxy is one of the most powerful starburst galaxies at high redshift (star formation rate; SFR~3600M_{sun}_/yr), with an extremely compact (~320pc) star formation region and a SFR surface density ({SIGMA}_SFR_~5500M_{sun}_/yr/kpc^2^) five times higher than "maximum" (i.e. Eddington-limited) starbursts, implying a highly transient phase. The estimated outflow rate is ~500M_{sun}_/yr, which is much lower than the SFR, implying that in this extreme starburst the outflow capabilities saturate and the outflow is no longer capable of regulating star formation, resulting in a runaway process in which star formation will use up all available gas in less than 30Myr. Finally, while previous kinematic investigations of this source revealed possible evidence for an ongoing major merger, the coincidence of the hyper-compact starburst and high-excitation water absorption indicates that this is a single starburst galaxy surrounded by a disc.
1505. High-Redshift Quasars (z>=2.2) in SGP and F401
ID:
ivo://CDS.VizieR/VII/182
Title:
High-Redshift Quasars (z>=2.2) in SGP and F401
Short Name:
VII/182
Date:
21 Oct 2021
Publisher:
CDS
Description:
(Paper I) We provide details of a multicolor ( u, b_j_, v, or, r, i), wide-field, faint magnitude survey for high-redshift (z >= 2.2 ) quasars. The survey extends over the magnitude range 16<=m_or_<=20 and covers a total area of 58.6 square degrees. Sources of incompleteness in the photometric catalog are quantified, giving the survey an effective area of 45.7 square degrees. Particular attention is paid to the details of the plate-matching and image-classification procedures used in the generation of the photometric catalog from which quasars are selected, in order that the number of spurious quasar candidates be kept to an absolute minimum. The selection of candidates incorporates a number of novel features, including treating the multicolor information as low-resolution spectra, adopting a quantitative candidate identification algorithm that employs all the available information, and requiring only that objects be detected in the or passband. We describe how model quasar spectra are used to calculate the selection function for the survey, and we present the computed sample completeness, as a function of redshift and magnitude, for a range of representative quasar types. The spectroscopic results of the survey are reported in a companion paper and the derivation of the quasar luminosity function at high redshift will be reported in a third paper. (Paper II; see also documentation files "doc.tex" or "doc.txt") In a wide-field multicolor survey (45.7 deg^2^, 16.0<=m_or_<=20.0) we have discovered 130 new quasars, of which 100 are of redshift z>=2.2. There are 49 new quasars of redshift z>=3.0 including three of z>=4.0. We provide spectra, coordinates, redshifts, broad-band magnitudes (u, b_j_, v, or, r, i), line-equivalent widths for Lyman-{alpha}/NV and CIV, FWHM CIV, and continuum spectral indices for all the new quasars. The sample includes 96 quasars selected according to the rigid criteria detailed in the companion paper by Warren, Hewett, Irwin, and Osmer. These are combined with 14 previously known quasars in one of our fields, which also meet these selection criteria, to form a complete sample. The median equivalent width for Lyman-{alpha}/NV for the complete sample is 67A, and for CIV is 31{AA}. The median FWHM CIV is 35{AA} and the median spectral index is {alpha}=-0.60. The complete sample contains at least five broad absorption-line quasars. We have obtained spectra of a total of 473 multicolor selected candidates. The proportion of quasars found, including previously known quasars, of all redshifts, is 30%. The proportion of quasars of redshift z>=2.2 in the list of candidates that satisfy the selection criteria of the complete sample is 43%. Finally we limit the sample to the 85 objects of redshift z>=2.2 in the complete sample, and summarize the relevant observational data input to the calculation of the luminosity function, comprising the redshift versus magnitude distribution and the distribution of the spectral properties. The analysis of the luminosity function will be presented in a forthcoming paper.
1506. High redshift radio galaxies emission lines
ID:
ivo://CDS.VizieR/J/A+A/362/519
Title:
High redshift radio galaxies emission lines
Short Name:
J/A+A/362/519
Date:
21 Oct 2021
Publisher:
CDS
Description:
This table gives radio and spectroscopic data for 167 radio galaxies, taken from the references given in the last column, from the WENSS, Texas and NVSS radio surveys, or determined from the electronic versions of the spectra.
1507. High resolution NIR observations of z>~1 galaxies
ID:
ivo://CDS.VizieR/J/ApJ/864/8
Title:
High resolution NIR observations of z>~1 galaxies
Short Name:
J/ApJ/864/8
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present images taken using the Gemini South Adaptive Optics Imager (GSAOI) with the Gemini Multi-conjugate Adaptive Optics System (GeMS) in three 2arcmin^2^ fields in the Spitzer Extragalactic Representative Volume Survey. These GeMS/GSAOI observations are among the first ~0.1" resolution data in the near-infrared spanning extragalactic fields exceeding 1.5' in size. We use these data to estimate galaxy sizes, obtaining results similar to those from studies with the Hubble Space Telescope, though we find a higher fraction of compact star-forming galaxies at z>2. To disentangle the star-forming galaxies from active galactic nuclei (AGNs), we use multiwavelength data from surveys in the optical and infrared, including far-infrared data from Herschel, as well as new radio continuum data from the Australia Telescope Compact Array and Very Large Array. We identify ultraluminous infrared galaxies (ULIRGs) at z~1-3, which consist of a combination of pure starburst galaxies and AGN/starburst composites. The ULIRGs show signs of recent merger activity, such as highly disturbed morphologies and include a rare candidate triple-AGN. We find that AGNs tend to reside in hosts with smaller scale sizes than purely star-forming galaxies of similar infrared luminosity. Our observations demonstrate the potential for MCAO to complement the deeper galaxy surveys to be made with the James Webb Space Telescope.
1508. High-z galaxy candidates in the HFF cluster fields
ID:
ivo://CDS.VizieR/J/ApJ/862/156
Title:
High-z galaxy candidates in the HFF cluster fields
Short Name:
J/ApJ/862/156
Date:
21 Oct 2021
Publisher:
CDS
Description:
Acting as powerful gravitational lenses, the strong lensing galaxy clusters of the deep Hubble Frontier Fields (HFF) program permit access to lower-luminosity galaxies lying at higher redshifts than hitherto possible. We analyzed the HFF to measure the volume density of Lyman-break galaxies at z>4.75 by identifying a complete and reliable sample up to z~10. A marked deficit of such galaxies was uncovered in the highly magnified regions of the clusters relative to their outskirts, implying that the magnification of the sky area dominates over additional faint galaxies magnified above the flux limit. This negative magnification bias is consistent with a slow rollover at the faint end of the UV luminosity function and it indicates a preference for Bose-Einstein condensate dark matter with a light boson mass of m_B_~10^-22^eV over standard cold dark matter. We emphasize that measuring the magnification bias requires no correction for multiply-lensed images (with typically three or more images per source), whereas directly reconstructing the luminosity function will lead to an overestimate unless such images can be exhaustively matched up, especially at the faint end that is only accessible in the strongly lensed regions. In addition, we detected a distinctive downward transition in galaxy number density at z>~8, which may be linked to the relatively late reionization reported by Planck. Our results suggests that JWST will likely peer into an "abyss" with essentially no galaxies detected in deep NIR imaging at z>10.
1509. High-z LAEs and LBGs in SHARDS survey
ID:
ivo://CDS.VizieR/J/MNRAS/478/3740
Title:
High-z LAEs and LBGs in SHARDS survey
Short Name:
J/MNRAS/478/3740
Date:
11 Mar 2022 14:56:32
Publisher:
CDS
Description:
We have undertaken a comprehensive search for both Lyman alpha emitters (LAEs) and Lyman break galaxies (LBGs) in the Survey for High-z Absorption Red and Dead Sources (SHARDS) Survey of the Great Observatories Origins Deep Survey North field. SHARDS is a deep imaging survey, made with the 10.4m Gran Telescopio Canarias, employing 25 medium band filters in the range from 500 to 941nm. This is the first time that both LAEs and LBGs are surveyed simultaneously in a systematic way in a large field. We draw a sample of 1558 sources; 528 of them are LAEs. Most of the sources (1434) show rest-frame UV continua. A minority of them (124) are pure LAEs with virtually no continuum detected in SHARDS. We study these sources from z~3.35 up to z~6.8, well into the epoch of reionization. Note that surveys done with just one or two narrow band filters lack the possibility to spot the rest-frame UV continuum present in most of our LAEs. We derive redshifts, star formation rates, Ly{alpha} equivalent widths, and luminosity functions (LFs). Grouping within our sample is also studied, finding 92 pairs or small groups of galaxies at the same redshift separated by less than 60 comoving kpc. In addition, we relate 87 and 55 UV-selected objects with two known overdensities at z=4.05 and z=5.198, respectively. Finally, we show that surveys made with broad-band filters are prone to introduce many unwanted sources (~20 per cent interlopers), which means that previous studies may be overestimating the calculated LFs, specially at the faint end.
1510. HI holes in THINGS galaxies
ID:
ivo://CDS.VizieR/J/AJ/141/23
Title:
HI holes in THINGS galaxies
Short Name:
J/AJ/141/23
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of the properties of HI holes detected in 20 galaxies that are part of "The HI Nearby Galaxy Survey." We detected more than 1000 holes in total in the sampled galaxies. Where they can be measured, their sizes range from about 100pc (our resolution limit) to about 2kpc, their expansion velocities range from 4 to 36km/s, and their ages are estimated to range between 3 and 150Myr. The holes are found throughout the disks of the galaxies, out to the edge of the HI disk; 23% of the holes fall outside R25. We find that shear limits the age of holes in spirals (shear is less important in dwarf galaxies) which explains why HI holes in dwarfs are rounder, on average than in spirals.