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3911. UGRK Photometry in the Hubble Deep field region
ID:
ivo://CDS.VizieR/J/ApJS/127/1
Title:
UGRK Photometry in the Hubble Deep field region
Short Name:
J/ApJS/127/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
Detection and photometry of sources in the U_n_, G, {R}, and K_s_ bands in a 9x9 arcmin^2^ region of the sky, centered on the Hubble Deep Field, are described. The data permit construction of complete photometric catalogs to roughly U_n_=25, G=26, {R}=25.5, K_s_=20 mag and significant photometric measurements somewhat fainter. Galaxy catalogs selected in the {R} and K_s_ bands are presented, containing 3607 and 488 sources in field areas of 74.8 and 59.4arcmin^2^, to {R}=25.5 and K_s_=20mag.
3912. UGR photometry of LBG candidates at z~3
ID:
ivo://CDS.VizieR/J/A+A/563/A142
Title:
UGR photometry of LBG candidates at z~3
Short Name:
J/A+A/563/A142
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a deep multi wavelength imaging survey (UGR) in 3 different fields, Q0933, Q1623 and COSMOS, for a total area of ~1500arcmin^2^ The data were obtained with the Large Binocular Camera on the Large Binocular Telescope. To select our LBG candidates we adopt the well established and widely used color selection criterion (U-G vs. G-R). One of the main advantages of our survey is that it has a wider dynamic color range for U drop-out selection compared to previous studies. This allows us to fully exploit the depth of our R band images, obtaining a robust sample with few interlopers. In addition, for 2 of our fields we have spectroscopic redshift information that is necessary to better estimate the completeness of our sample and interloper fraction. Our limiting magnitudes reach 27.0(AB) in the R band (5{sigma}) and 28.6(AB) in the U band (1{sigma}). This dataset was used to derive Lyman Break Galaxy candidates at z~3. We obtained a catalog with a total of 12264 sources down to the 50% completeness magnitude limit in the R band for each field. We find a surface density of ~3 LBG candidates arcmin^-2^ down to R=25.5, where completeness is >=95% for all 3 fields. This number is higher than the original studies, but consistent with more recent samples.
3913. UKIDSS UDS field spectroscopic redshifts
ID:
ivo://CDS.VizieR/J/MNRAS/475/4148
Title:
UKIDSS UDS field spectroscopic redshifts
Short Name:
J/MNRAS/475/4148
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a large-scale galaxy structure Cl J021734-0513 at z~0.65 discovered in the UKIDSS UDS field, made of ~20 galaxy groups and clusters, spreading over 10Mpc. We report on a VLT/VIMOS spectroscopic follow-up program that, combined with past spectroscopy, allowed us to confirm four galaxy clusters (M_200_~10^14^M_{sun}_) and a dozen associated groups and star-forming galaxy overdensities. Two additional filamentary structures at z~0.62 and 0.69 and foreground and background clusters at 0.6<z<0.7 were also confirmed along the line of sight. The structure subcomponents are at different formation stages. The clusters have a core dominated by passive galaxies and an established red sequence. The remaining structures are a mix of star-forming galaxy overdensities and forming groups. The presence of quiescent galaxies in the core of the latter shows that 'pre-processing' has already happened before the groups fall into their more massive neighbours. Our spectroscopy allows us to derive spectral index measurements e.g. emission/absorption line equivalent widths, strength of the 4000{AA} break, valuable to investigate the star formation history of structure members. Based on these line measurements, we select a population of 'post-starburst' galaxies. These galaxies are preferentially found within the virial radius of clusters, supporting a scenario in which their recent quenching could be prompted by gas stripping by the dense intracluster medium. We derive stellar age estimates using Markov Chain Monte Carlo-based spectral fitting for quiescent galaxies and find a correlation between ages and colours/stellar masses which favours a top-down formation scenario of the red sequence. A catalogue of ~650 redshifts in UDS is released alongside the paper (via MNRAS online data).
3914. UKIRT NIR and Spitzer MIR phot. in NGC 6822
ID:
ivo://CDS.VizieR/J/ApJ/892/91
Title:
UKIRT NIR and Spitzer MIR phot. in NGC 6822
Short Name:
J/ApJ/892/91
Date:
19 Jan 2022 08:59:33
Publisher:
CDS
Description:
The nearby (~500kpc) metal-poor ([Fe/H]~-1.2; Z~30%Z_{sun}_) star-forming galaxy NGC 6822 has a metallicity similar to systems at the epoch of peak star formation. Through identification and study of dusty and dust-producing stars, it is therefore a useful laboratory to shed light on the dust life cycle in the early universe. We present a catalog of sources combining near- and mid-IR photometry from the United Kingdom Infrared Telescope (J, H, and K) and the Spitzer Space Telescope (IRAC 3.6, 4.5, 5.8, and 8.0{mu}m and MIPS 24{mu}m). This catalog is employed to identify dusty and evolved stars in NGC 6822 utilizing three color-magnitude diagrams (CMDs). With diagnostic CMDs covering a wavelength range spanning the near- and mid-IR, we develop color cuts using kernel density estimate (KDE) techniques to identify dust-producing evolved stars, including red supergiant (RSG) and thermally pulsing asymptotic giant branch (TP-AGB) star candidates. In total, we report 1292 RSG candidates, 1050 oxygen-rich AGB star candidates, and 560 carbon-rich AGB star candidates with high confidence in NGC 6822. Our analysis of the AGB stars suggests a robust population inhabiting the central stellar bar of the galaxy, with a measured global stellar metallicity of [Fe/H]=-1.286+/-0.095, consistent with previous studies. In addition, we identify 277 young stellar object (YSO) candidates. The detection of a large number of YSO candidates within a centrally located, compact cluster reveals the existence of an embedded, high-mass star formation region that has eluded previous detailed study. Spitzer I appears to be younger and more active than the other prominent star-forming regions in the galaxy.
3915. UKIRT obs. of red supergiants in M31
ID:
ivo://CDS.VizieR/J/ApJ/889/44
Title:
UKIRT obs. of red supergiants in M31
Short Name:
J/ApJ/889/44
Date:
17 Jan 2022 11:49:04
Publisher:
CDS
Description:
The mass-loss rates of red supergiant stars (RSGs) are poorly constrained by direct measurements, and yet the subsequent evolution of these stars depends critically on how much mass is lost during the RSG phase. In 2012 the Geneva evolutionary group updated their mass-loss prescription for RSGs with the result that a 20M_{sun}_ star now loses 10 times more mass during the RSG phase than in the older models. Thus, higher-mass RSGs evolve back through a second yellow supergiant phase rather than exploding as Type II-P supernovae, in accord with recent observations (the so-called "RSG Problem"). Still, even much larger mass-loss rates during the RSG phase cannot be ruled out by direct measurements of their current dust-production rates, as such mass loss is episodic. Here, we test the models by deriving a luminosity function for RSGs in the nearby spiral galaxy, M31, which is sensitive to the total mass loss during the RSG phase. We carefully separate RSGs from asymptotic giant branch stars in the color-magnitude diagram following the recent method exploited by Yang+ (2019, J/A+A/629/A91) in their Small Magellanic Cloud studies. Comparing our resulting luminosity function with that predicted by the evolutionary models shows that the new prescription for RSG mass loss does an excellent job of matching the observations, and we can readily rule out significantly larger values.
3916. ULIRGs galaxies in SDSS, 2dF and 6dF
ID:
ivo://CDS.VizieR/J/MNRAS/375/115
Title:
ULIRGs galaxies in SDSS, 2dF and 6dF
Short Name:
J/MNRAS/375/115
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a result of cross-correlating the Infrared Astronomical Satellite Faint Source Catalogue with the spectroscopic catalogues of galaxies in the Fourth Data Release of the Sloan Digital Sky Survey, the Final Data Release of the 2dF Galaxy Redshift Survey (2dFGRS) and the Second Data Release of the 6dF Galaxy Survey. We have identified 324 ultraluminous infrared galaxies (ULIRGs) including 190 newly discovered ULIRGs, and two hyperluminous infrared galaxies. Adding these new ULIRGs, we increase the number of known ULIRGs by about 30 per cent. The reliability of the cross-correlation is estimated using the likelihood ratio method.
3917. ULIRGs in the AKARI all-sky survey
ID:
ivo://CDS.VizieR/J/ApJ/797/54
Title:
ULIRGs in the AKARI all-sky survey
Short Name:
J/ApJ/797/54
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new catalog of 118 ultraluminous infrared galaxies (ULIRGs) and one hyperluminous infrared galaxy (HLIRG) by cross-matching the AKARI all-sky survey with the Sloan Digital Sky Survey Data Release 10 (SDSS DR10) and the final data release of the Two-Degree Field Galaxy Redshift Survey. Forty of the ULIRGs and one HLIRG are new identifications. We find that ULIRGs are interacting pair galaxies or ongoing or postmergers. This is consistent with the widely accepted view: ULIRGs are major mergers of disk galaxies. We confirm the previously known positive trend between the active galactic nucleus fraction and infrared luminosity. We show that ULIRGs have a large offset from the main sequence up to z ~ 1; their offset from the z ~ 2 "main sequence" is relatively smaller. We find a result consistent with the previous studies showing that, compared to local star-forming SDSS galaxies of similar mass, local ULIRGs have lower oxygen abundances. We demonstrate for the first time that ULIRGs follow the fundamental metallicity relation (FMR). The scatter of ULIRGs around the FMR (0.09 dex-0.5 dex) is comparable to the scatter of z ~ 2-3 galaxies. We provide the largest local (0.050 <z < 0.487) ULIRG catalog with stellar masses, star-formation rates, gas metallicities, and optical colors.
3918. [U]LIRGs - on the trail of AGN's types
ID:
ivo://CDS.VizieR/J/A+A/598/A1
Title:
[U]LIRGs - on the trail of AGN's types
Short Name:
J/A+A/598/A1
Date:
21 Oct 2021
Publisher:
CDS
Description:
The aim of this work is to characterize physical properties of Ultra Luminous Infrared Galaxies (ULIRGs) and Luminous Infrared Galaxies (LIRGs) detected in the far-infrared (FIR) 90um band in the AKARI Deep Field-South (ADF-S) survey. In particular, we want to estimate the active galactic nucleus (AGN) contribution to the LIRGs and ULIRGs' infrared emission and which types of AGNs are related to their activity. We examined 69 galaxies at redshift >=0.05 detected at 90um by the AKARI satellite in the AKARI Deep-Field South (ADF-S), with optical counterparts and spectral coverage from the ultraviolet to the FIR. We used two independent spectral energy distribution fitting codes: one fitting the SED from FIR to FUV (CIGALE) (we use the results from CIGALE as a reference) and gray-body + power spectrum fit for the infrared part of the spectra (CMCIRSED) in order to identify a subsample of ULIRGs and LIRGs, and to estimate their properties. A final catalog of 39 LIRGs and ULIRGs is used for our analysis.
3919. Ultra-compact dwarf candidates in Abell S0740
ID:
ivo://CDS.VizieR/J/AJ/136/2295
Title:
Ultra-compact dwarf candidates in Abell S0740
Short Name:
J/AJ/136/2295
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyze three-band imaging data of the giant elliptical galaxy ESO 325-G004 from the Hubble Space Telescope Advanced Camera for Surveys (ACS). This is the nearest known strongly lensing galaxy, and it resides in the center of the poor cluster Abell S0740 at redshift z=0.034. Based on magnitude, color, and size selection criteria, we identify a sample of 15 ultra-compact dwarf (UCD) galaxy candidates within the ACS field.
3920. Ultra compact dwarf galaxies catalog
ID:
ivo://CDS.VizieR/J/A+A/625/A50
Title:
Ultra compact dwarf galaxies catalog
Short Name:
J/A+A/625/A50
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photometric surveys of galaxy clusters have revealed a large number of ultra compact dwarfs (UCDs) around predominantly massive elliptical galaxies. Their origin is still debated as some UCDs are considered to be the remnant nuclei of stripped dwarf galaxies while others seem to mark the high-mass end of the star cluster population. We aim to characterize the properties of a UCD found at very close projected distance (r_wproj_=1.1kpc) from the centre of the low-mass (M~10^10^M_{sun}_) early-type galaxy FCC 47. This is a serendipitous discovery from MUSE adaptive optics science verification data. We explore the potential origin of this UCD as either a massive cluster or the remnant nucleus of a dissolved galaxy. We used archival Hubble Space Telescope data to study the photometric and structural properties of FCC 47-UCD1. In the MUSE data, the UCD is unresolved, but we used its spectrum to determine the radial velocity and metallicity. The surface brightness of FCC 47-UCD1 is best described by a single King profile with low concentration C=Rt/Rc~10 and large effective radius (r_eff_=24pc). Its integrated magnitude and blue colour (Mg=-10.55mag, (g-z)=1.46mag) combined with a metallicity of [M/H]=-1.12+/-0.10dex and an age >8Gyr obtained from the full fitting of the MUSE spectrum suggests a stellar population mass of M*=4.87x10^6^M_{sun}_. The low S/N of the MUSE spectrum prevents detailed stellar population analysis. Due to the limited spectral resolution of MUSE, we can only give an upper limit on the velocity dispersion ({sigma}<17km/s), and consequently on its dynamical mass (M_dyn_<1.3x10^7^M_{sun}_). The origin of the UCD cannot be constrained with certainty. The low metallicity, old age, and magnitude are consistent with a star cluster origin, whereas the extended size is consistent with an origin as the stripped nucleus of a dwarf galaxy with a initial stellar mass of a few 10^8^M_{sun}_.

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