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1331. GMRT observations of head-tail radio galaxies
ID:
ivo://CDS.VizieR/J/AJ/154/169
Title:
GMRT observations of head-tail radio galaxies
Short Name:
J/AJ/154/169
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from a study of seven large known head-tail radio galaxies based on observations using the Giant Metrewave Radio Telescope at 240 and 610 MHz. These observations are used to study the radio morphologies and distribution of the spectral indices across the sources. The overall morphology of the radio tails of these sources is suggestive of random motions of the optical host around the cluster potential. The presence of multiple bends and wiggles in several head-tail sources is possibly due to the precessing radio jets. We find steepening of the spectral index along the radio tails. The prevailing equipartition magnetic field also decreases along the radio tails of these sources. These steepening trends are attributed to the synchrotron aging of plasma toward the ends of the tails. The dynamical ages of these sample sources have been estimated to be ~10^8^ yr, which is a factor of six more than the age estimates from the radiative losses due to synchrotron cooling.
1332. GMRT radios sources around J0916+6348 field
ID:
ivo://CDS.VizieR/J/MNRAS/392/1403
Title:
GMRT radios sources around J0916+6348 field
Short Name:
J/MNRAS/392/1403
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep multifrequency observations using the Giant Metrewave Radio Telescope (GMRT) at 153, 244, 610 and 1260MHz of a field centred on J0916+6348, to search for evidence of fossil radio lobes which could be due to an earlier cycle of episodic activity of the parent galaxy, as well as haloes and relics in clusters of galaxies. We do not find any unambiguous evidence of episodic activity in a list of 374 sources, suggesting that such activity is rare even in relatively deep low-frequency observations. We examine the spectra of all the sources by combining our observations with those from the Westerbork Northern Sky Survey (WENSS), NRAO (National Radio Astronomy Observatories) VLA (Very Large Array) Sky Survey (NVSS) and the Faint Images of the Radio Sky at Twenty-Centimeters Survey (FIRST).
1333. GMVA 86GHz Stokes IQU images of 3C84 jet
ID:
ivo://CDS.VizieR/J/A+A/622/A196
Title:
GMVA 86GHz Stokes IQU images of 3C84 jet
Short Name:
J/A+A/622/A196
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report results from a deep polarization imaging of the nearby radio galaxy 3C 84 (NGC 1275). The source was observed with the Global Millimeter VLBI Array (GMVA) at 86GHz at an ultrahigh angular resolution of 50{mu}as (corresponding to 200Rs). We also add complementary multiwavelength data from the Very Long Baseline Array (VLBA; 15 & 43GHz) and from the Atacama Large Millimeter/submillimeter Array (ALMA; 97.5, 233.0, and 343.5GHz). At 86GHz, we measured a fractional linear polarization of ~2% in the VLBI core region. The polarization morphology suggests that the emission is associated with an underlying limb-brightened jet. The fractional linear polarization is lower at 43 and 15GHz (~0.3-0.7% and <0.1%, respectively). This suggests an increasing linear polarization degree toward shorter wavelengths on VLBI scales. We also obtain a large rotation measure (RM) of ~10^5-6^rad/m^2^ in the core at >~43GHz. Moreover, the VLBA 43GHz observations show a variable RM in the VLBI core region during a small flare in 2015. Faraday depolarization and Faraday conversion in an inhomogeneous and mildly relativistic plasma could explain the observed linear polarization characteristics and the previously measured frequency dependence of the circular polarization. Our Faraday depolarization modeling suggests that the RM most likely originates from an external screen with a highly uniform RM distribution. To explain the large RM value, the uniform RM distribution, and the RM variability, we suggest that the Faraday rotation is caused by a boundary layer in a transversely stratified jet. Based on the RM and the synchrotron spectrum of the core, we provide an estimate for the magnetic field strength and the electron density of the jet plasma.
1334. GOALS sample PACS and SPIRE fluxes
ID:
ivo://CDS.VizieR/J/ApJS/229/25
Title:
GOALS sample PACS and SPIRE fluxes
Short Name:
J/ApJS/229/25
Date:
21 Oct 2021
Publisher:
CDS
Description:
Far-infrared images and photometry are presented for 201 Luminous and Ultraluminous Infrared Galaxies [LIRGs: log(L_IR_/L_{sun}_)=11.00-11.99, ULIRGs: log(L_IR_/L_{sun}_)=12.00-12.99], in the Great Observatories All-Sky LIRG Survey (GOALS), based on observations with the Herschel Space Observatory Photodetector Array Camera and Spectrometer (PACS) and the Spectral and Photometric Imaging Receiver (SPIRE) instruments. The image atlas displays each GOALS target in the three PACS bands (70, 100, and 160{mu}m) and the three SPIRE bands (250, 350, and 500{mu}m), optimized to reveal structures at both high and low surface brightness levels, with images scaled to simplify comparison of structures in the same physical areas of ~100x100kpc^2^. Flux densities of companion galaxies in merging systems are provided where possible, depending on their angular separation and the spatial resolution in each passband, along with integrated system fluxes (sum of components). This data set constitutes the imaging and photometric component of the GOALS Herschel OT1 observing program, and is complementary to atlases presented for the Hubble Space Telescope, Spitzer Space Telescope, and Chandra X-ray Observatory. Collectively, these data will enable a wide range of detailed studies of active galactic nucleus and starburst activity within the most luminous infrared galaxies in the local universe.
1335. GOALS UV and FIR properties
ID:
ivo://CDS.VizieR/J/ApJ/715/572
Title:
GOALS UV and FIR properties
Short Name:
J/ApJ/715/572
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Great Observatories All-sky LIRG Survey (GOALS) consists of a complete sample of 202 luminous infrared galaxies (LIRGs) selected from the IRAS Revised Bright Galaxy Sample (RBGS; Sanders et al. 2003, Cat. J/AJ/126/1607). The galaxies span the full range of interaction stages, from isolated galaxies to interacting pairs to late stage mergers. We present a comparison of the UV and infrared properties of 135 galaxies in GOALS observed by GALEX and Spitzer. For interacting galaxies with separations greater than the resolution of GALEX and Spitzer (~2"-6"), we assess the UV and IR properties of each galaxy individually. The contribution of the FUV to the measured star formation rate (SFR) ranges from 0.2% to 17.9%, with a median of 2.8% and a mean of 4.0+/-0.4%. The specific star formation rate (SSFR) of the GOALS sample is extremely high, with a median value (3.9x10^-10^/yr) that is comparable to the highest SSFRs seen in the Spitzer Infrared Nearby Galaxies Survey sample. We examine the position of each galaxy on the IR excess-UV slope (IRX-{beta}) diagram as a function of galaxy properties, including IR luminosity and interaction stage.
1336. GOLDRUSH I. UV magnitudes
ID:
ivo://CDS.VizieR/J/PASJ/70/S10
Title:
GOLDRUSH I. UV magnitudes
Short Name:
J/PASJ/70/S10
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the UV luminosity functions (LFs) at z~4, 5, 6, and 7 based on the deep large-area optical images taken by the Hyper Suprime-Cam (HSC) Subaru Strategic Program (SSP). On the 100 deg^2^ sky of the HSC SSP data available to date, we take enormous samples consisting of a total of 579565 dropout candidates at z~4-7 by the standard color selection technique, 358 out of which are spectroscopically confirmed by our follow-up spectroscopy and other studies. We obtain UV LFs at z~4-7 that span a very wide UV luminosity range of ~0.002-100L^*^_UV_(-26<M_UV_<-14mag) by combining LFs from our program and the ultra-deep Hubble Space Telescope legacy surveys. We derive three parameters of the best-fit Schechter function, {Phi}^*^, M_UV_, and {alpha}, of the UV LFs in the magnitude range where the active galactic nucleus (AGN) contribution is negligible, and find that and {Phi}^*^ decrease from z~4 to 7 with no significant evolution of M_UV_. Because our HSC SSP data bridge the LFs of galaxies and AGNs with great statistical accuracy, we carefully investigate the bright end of the galaxy UV LFs that are estimated by the subtraction of the AGN contribution either aided by spectroscopy or the best-fit AGN UV LFs. We find that the bright end of the galaxy UV LFs cannot be explained by the Schechter function fits at >2{sigma} significance, and require either double power-law functions or modified Schechter functions that consider a magnification bias due to gravitational lensing.
1337. GOODS blue early-type galaxies
ID:
ivo://CDS.VizieR/J/ApJ/650/148
Title:
GOODS blue early-type galaxies
Short Name:
J/ApJ/650/148
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a study of the nature of the blue early-type galaxies (BEGs) in the GOODS North and South fields using the GOODS archival HST ACS data. Using visual inspection, we have selected 58 BEGs and 113 normal red early-type galaxies (REGs) in the sample of 1949 galaxies with spectroscopic redshifts. We find that the BEGs are generally bluer, fainter, and less massive than the REGs, although a few BEGs are exceptionally bright and massive. The number fraction of BEGs to total early-type galaxies is almost constant (~0.3) at z<=1.1. In addition, we find that the sizes of the BEGs in a given redshift bin decrease as redshift decreases. The BEGs look similar to the REGs in the images and surface brightness profiles.
1338. GOODS-Herschel North and South catalogs
ID:
ivo://CDS.VizieR/J/A+A/533/A119
Title:
GOODS-Herschel North and South catalogs
Short Name:
J/A+A/533/A119
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the deepest 100 to 500{mu}m far-infrared observations obtained with the Herschel Space Observatory as part of the GOODS-Herschel key program, and examine the infrared (IR) 3-500{mu}m spectral energy distributions (SEDs) of galaxies at 0<z<2.5, supplemented by a local reference sample from IRAS, ISO, Spitzer, and AKARI data. We determine the projected star formation densities of local galaxies from their radio and mid-IR continuum sizes.
1339. GOODS initial results
ID:
ivo://CDS.VizieR/II/261
Title:
GOODS initial results
Short Name:
II/261
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present initial results from the Great Observatories Origins Deep Survey (GOODS) that are primarily, but not exclusively, based on multiband imaging data obtained with the Hubble Space Telescope and the Advanced Camera for Surveys (ACS). The survey covers roughly 320 arcmin2 in the ACS F435W, F606W, F814W, and F850LP bands, divided into two well-studied fields. Existing deep observations from the Chandra X-Ray Observatory and ground-based facilities are supplemented with new, deep imaging in the optical and near-infrared from the European Southern Observatory and from the Kitt Peak National Observatory. Deep observations with the Space Infrared Telescope Facility are scheduled. Reduced data from all facilities are being released worldwide within 36 months of acquisition. Together, this data set provides two deep reference fields for studies of distant normal and active galaxies, supernovae, and faint stars in our own Galaxy. This Letter serves to outline the survey strategy and describe the specific data that have been used in the accompanying letters, summarizing the reduction procedures and sensitivity limits.
1340. GOODS Ks-selected multiwavelength compilations
ID:
ivo://CDS.VizieR/J/ApJ/697/1369
Title:
GOODS Ks-selected multiwavelength compilations
Short Name:
J/ApJ/697/1369
Date:
21 Oct 2021
Publisher:
CDS
Description:
Ks-selected multiwavelength compilations in GOODS.