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861. Large Quasar Astrometric Catalogue (LQAC)
ID:
ivo://CDS.VizieR/J/A+A/494/799
Title:
Large Quasar Astrometric Catalogue (LQAC)
Short Name:
J/A+A/494/799
Date:
21 Oct 2021
Publisher:
CDS
Description:
The very large and increasing number of quasars reckoned from various sky surveys leads to a large quantity of data which brings various and inhomogeneous information in the fields of astrometry, photometry, radioastronomy and spectroscopy. In this paper, we describe our work that aims to make available a general compilation of the largest number of recorded quasars obtained from all the available catalogues, with their best position estimates, and providing physical information at both optical and radio wavelengths.
862. Large scale [CII] emission from the OMC
ID:
ivo://CDS.VizieR/J/A+A/652/A77
Title:
Large scale [CII] emission from the OMC
Short Name:
J/A+A/652/A77
Date:
22 Feb 2022
Publisher:
CDS
Description:
The [CII] 158um far-infrared (FIR) fine-structure line is one of the dominant cooling lines of the star-forming interstellar medium (ISM). Hence [CII] emission originates in, and thus can be used to trace a range of ISM processes. Velocity resolved large scale mapping of [CII] in star forming regions provides a unique perspective on the kinematics of these regions and their interactions with the exciting source of radiation. In this paper we explore the scientific applications of large scale mapping velocity resolved [CII] observations. With [CII] observations we investigate the influence of stellar feedback on the ISM. We present the details of observation, calibration and data reduction using a heterodyne array receiver mounted on an airborne observatory. A 1.15 square degree velocity resolved map of Orion molecular cloud centred on the bar region was observed using the upGREAT heterodyne receiver flying on-board the Stratospheric Observatory for Infrared Astronomy (SOFIA). The data was acquired using the 14 pixels of the German REceiver for Astronomy at Terahertz Frequencies (upGREAT) observing in an on-the-fly mapping mode. 2.4 million spectra were taken in total. These spectra were gridded into a three dimensional cube with a spatial resolution of 14.1 arcseconds and spectral resolution of 0.3km/s.
863. LARGESS survey
ID:
ivo://CDS.VizieR/J/MNRAS/464/1306
Title:
LARGESS survey
Short Name:
J/MNRAS/464/1306
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Large Area Radio Galaxy Evolution Spectroscopic Survey (LARGESS), a spectroscopic catalogue of radio sources designed to include the full range of radio AGN populations out to redshift z~0.8. The catalogue covers ~800deg^2^ of sky, and provides optical identifications for 19179 radio sources from the 1.4GHz Faint Images of the Radio Sky at Twenty-cm (FIRST) survey down to an optical magnitude limit of i_mod_<20.5 in Sloan Digital Sky Survey (SDSS) images. Both galaxies and point-like objects are included, and no colour cuts are applied. In collaboration with the WiggleZ and Galaxy And Mass Assembly (GAMA) spectroscopic survey teams, we have obtained new spectra for over 5000 objects in the LARGESS sample. Combining these new spectra with data from earlier surveys provides spectroscopic data for 12329 radio sources in the survey area, of which 10 856 have reliable redshifts. 85 per cent of the LARGESS spectroscopic sample are radio AGN (median redshift z=0.44), and 15 per cent are nearby star-forming galaxies (median z=0.08). Low-excitation radio galaxies (LERGs) comprise the majority (83 per cent) of LARGESS radio AGN at z<0.8, with 12 per cent being high-excitation radio galaxies (HERGs) and 5 per cent radio-loud QSOs. Unlike the more homogeneous LERG and QSO sub-populations, HERGs are a heterogeneous class of objects with relatively blue optical colours and a wide dispersion in mid-infrared colours. This is consistent with a picture in which most HERGs are hosted by galaxies with recent or ongoing star formation as well as a classical accretion disc.
864. LBA Calibrator Survey (LCS1)
ID:
ivo://CDS.VizieR/J/MNRAS/414/2528
Title:
LBA Calibrator Survey (LCS1)
Short Name:
J/MNRAS/414/2528
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of accurate positions and correlated flux densities for 410 flat-spectrum, compact extragalactic radio sources previously detected in the AT20G survey. The catalogue spans the declination range [-90{deg}, -40{deg}] and was constructed from four 24-hour VLBI observing sessions with the Australian Long Baseline Array at 8.3GHz. The VLBI detection rate in these experiments is 97%, the median uncertainty of the source positions is 2.6mas, and the median correlated flux density on projected baselines longer than 1000km is 0.14Jy. The goals of this work are 1) to provide a pool of southern sources with positions accurate to a few milliarcsec, which can be used for phase referencing observations, geodetic VLBI and space navigation; 2) to extend the complete flux-limited sample of compact extragalactic sources to the southern hemisphere; and 3) to investigate the parsec-scale properties of high-frequency selected sources from the AT20G survey. As a result of this VLBI campaign, the number of compact radio sources south of declination -40 deg which have measured VLBI correlated flux densities and positions known to milliarcsec accuracy has increased by a factor of 3.5. The catalogue and supporting material is available at http://astrogeo.org/lcs1.
865. L1157-B1 DCN (2-1) and H^13^CN (2-1) datacubes
ID:
ivo://CDS.VizieR/J/A+A/604/A20
Title:
L1157-B1 DCN (2-1) and H^13^CN (2-1) datacubes
Short Name:
J/A+A/604/A20
Date:
21 Oct 2021
Publisher:
CDS
Description:
We performed high-angular-resolution observations toward L1157-B1 with the IRAM NOEMA interferometer of the DCN (2-1) and H^13^CN (2-1) lines to compute the deuterated fraction, D_frac_(HCN), and compare it with previously reported D_frac_ of other molecular species. Our aim is to observationally investigate the role of the different chemical processes at work that lead to formation of the DCN and compare it with HDCO, the two deuterated molecules imaged with an interferometer, and test the predictions of the chemical models for their formation.
866. 2LC Compact Radio Sources in the galactic center
ID:
ivo://CDS.VizieR/J/ApJS/174/481
Title:
2LC Compact Radio Sources in the galactic center
Short Name:
J/ApJS/174/481
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have used the VLA at 1.4GHz to survey the inner 2{deg} of the Galactic center for radio pulsar candidates. Because of the large pulse broadening suffered by Galactic center radio pulsars, our strategy has been to identify compact radio sources, without regard to whether they are pulsed radio sources. We describe our survey and present the catalog of 170 sources. Comparison with other radio surveys of the area shows that just over half of these sources have not been detected previously; this same comparison reveals 29 sources that are not in higher frequency surveys, suggesting that the sources are either variable or steep spectrum, and a comparable number of sources in other surveys that should have been detected in this survey but were not. Comparison with infrared surveys shows that 59 (35%) sources have infrared counterparts and are likely to be HII regions.
867. Leiden/Argentine/Bonn (LAB) Survey of Galactic HI
ID:
ivo://CDS.VizieR/VIII/76
Title:
Leiden/Argentine/Bonn (LAB) Survey of Galactic HI
Short Name:
VIII/76
Date:
21 Oct 2021
Publisher:
CDS
Description:
The LAB survey contains the final data release of observations of 21-cm emission from Galactic neutral hydrogen over the entire sky, merging the Leiden/Dwingeloo Survey (LDS: Hartmann & Burton 1997, Cat. VIII/54) of the sky north of -30{deg} with the Instituto Argentino de Radioastronomia Survey (IAR: Arnal et al. 2000A&AS..142...35A and Bajaja et al. 2005, Cat. VIII/75) of the sky south of -25{deg}. The angular resolution of the combined material is HPBW ~ 0.6{deg}. The LSR velocity coverage spans the interval -450 km/s to +400 km/s, at a resolution of 1.3km/s. The data were corrected for stray radiation at the Institute for Radioastronomy of the University of Bonn, refining the original correction applied to the LDS. The rms brightness-temperature noise of the merged database is 0.07-0.09 K. Residual errors in the profile wings due to defects in the correction for stray radiation are for most of the data below a level of 20-40 mK. It would be necessary to construct a telescope with a main beam efficiency of {eta}MB>99% to achieve the same accuracy. The merged and refined material entering the LAB Survey of Galactic H I is intended to be a general resource useful to a wide range of studies of the physical and structural characteristices of the Galactic interstellar environment. The LAB Survey is the most sensitive Milky Way H I survey to date, with the most extensive coverage both spatially and kinematically. The Survey is available as 3-D maps, with or without Hanning smoothing, covering the whole +/-458km/s or limited to +/-250km/s range. The resolution of the 3-D maps is 0.5{deg} in galactic longitude and latitude, and up to 1km/s in velocity. The survey exists also as (b,v) maps at longitude intervals stepped by 0.5{deg} -- these files supersedes the FITS files given in the Hartmann and Burton Atlas (Cat. VIII/54)
868. L1188 HCO+, 12CO and 13CO datacubes
ID:
ivo://CDS.VizieR/J/A+A/632/A115
Title:
L1188 HCO+, 12CO and 13CO datacubes
Short Name:
J/A+A/632/A115
Date:
21 Oct 2021
Publisher:
CDS
Description:
In order to search for further observational evidence of cloud-cloud collisions in one of the promising candidates, L1188, we carried out observations of multiple molecular lines toward the intersection region of the two nearly orthogonal filamentary molecular clouds in L1188. Based on these observations, we find two parallel filamentary structures, both of which have at least two velocity components being connected with broad bridging features. We also found a spatially complementary distribution between the two molecular clouds, as well as enhanced ^13^CO emission and ^12^CO self-absorption toward their abutting regions. At the most blueshifted velocities, we unveiled a 1pc-long arc ubiquitously showing ^12^CO line wings. We discovered two 22GHz water masers, which are the first maser detections in L1188. An analysis of line ratios at a linear resolution of 0.2 pc suggests that L1188 is characterised by kinetic temperatures of 13-23K and H_2_ number densities of 10^3^-10^3.6^cm^-3^. On the basis of previous theoretical predictions and simulations, we suggest that these observational features can be naturally explained by the scenario of a cloud-cloud collision in L1188, although an additional contribution of stellar feedback from low-mass young stellar objects cannot be ruled out.
869. Light curves of 3C273 during 2015-2019
ID:
ivo://CDS.VizieR/J/A+A/636/A62
Title:
Light curves of 3C273 during 2015-2019
Short Name:
J/A+A/636/A62
Date:
21 Oct 2021
Publisher:
CDS
Description:
The powerful radiation over the entire electromagnetic spectrum and its radio jet activity of the blazar 3C 273 offer the opportunity of studying the physics of {gamma}-ray emission from active galactic nuclei. Since the historically strong outburst in 2009, 3C 273 showed relatively weak emission in the {gamma}-ray band over several years. However, recent Fermi-Large Area Telescope observations indicate higher activity during 2015-2019. We constrain the origin of the {gamma}-ray outbursts toward 3C 273 and investigate their connection to the parsec-scale jet. We generated Fermi-LAT {gamma}-ray light curves with multiple binning intervals and studied the spectral properties of the {gamma}-ray emission. Using a 3mm ALMA light curve, we studied the correlation between radio and {gamma}-ray emission. The relevant activity in the parsec-scale jet of 3C 273 was investigated with 7 mm VLBA observations that were obtained close in time to notable {gamma}-ray outbursts. We find two prominent {gamma}-ray outbursts in 2016 (MJD 57382) and 2017 (MJD 57883) accompanied by millimeter-wavelength flaring activity. The {gamma}-ray photon index time series show a weak hump-like feature around the {gamma}-ray outbursts. The monthly {gamma}-ray flux-index plot indicates a transition from softer-when-brighter to harder-when-brighter states at 1.03x10^-7^ph/cm^2^/s. A significant correlation between the {gamma}-ray and millimeter-wavelength emission is found, and the radio lags the {gamma}-rays by about 105-112 days. The 43GHz jet images reveal the known stationary features (i.e., the core, S1, and S2) in a region upstream of the jet. We find an indication for a propagating disturbance and a polarized knot between the stationary components at about the times of the two {gamma}-ray outbursts. Our results support a parsec-scale origin for the observed higher {gamma}-ray activity, which suggests that this is associated with standing shocks in the jet.
870. Light curves of flat-spectrum radio sources
ID:
ivo://CDS.VizieR/J/MNRAS/401/1240
Title:
Light curves of flat-spectrum radio sources
Short Name:
J/MNRAS/401/1240
Date:
21 Oct 2021
Publisher:
CDS
Description:
Calibrated data for 143 flat-spectrum extragalactic radio sources are presented at a wavelength of 850um covering a 5-yr period from 2000 April. The data, obtained at the James Clerk Maxwell Telescope using the Submillimetre Common-User Bolometer Array (SCUBA) camera in pointing mode, were analysed using an automated pipeline process based on the Observatory Reduction and Acquisition Control - Data Reduction (ORAC-DR) system. This paper describes the techniques used to analyse and calibrate the data, and presents the data base of results along with a representative sample of the better-sampled light curves. A re-analysis of previously published data from 1997 to 2000 is also presented. The combined catalogue, comprising 10493 flux density measurements, provides a unique and valuable resource for studies of extragalactic radio sources.