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1301. Radio Ammonia Mid-plane Survey (RAMPS) pilot survey
ID:
ivo://CDS.VizieR/J/ApJS/237/27
Title:
Radio Ammonia Mid-plane Survey (RAMPS) pilot survey
Short Name:
J/ApJS/237/27
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Radio Ammonia Mid-Plane Survey (RAMPS) is a molecular line survey that aims to map a portion of the Galactic midplane in the first quadrant of the Galaxy (l=10{deg}-40{deg}, |b|<=0.4{deg}) using the Green Bank Telescope. We present results from the pilot survey, which has mapped approximately 6.5 square degrees in fields centered at l=10{deg}, 23{deg}, 24{deg}, 28{deg}, 29{deg}, 30{deg}, 31{deg}, 38{deg}, 45{deg}, and 47{deg}. RAMPS observes the NH3 inversion transitions NH_3_(1,1)-(5,5), the H_2_O 6_1,6_-5_2,3_ maser line at 22.235GHz, and several other molecular lines. We present a representative portion of the data from the pilot survey, including NH_3_(1,1) and NH_3_(2,2) integrated intensity maps, H_2_O maser positions, maps of NH_3_ velocity, NH_3_ line width, total NH_3_ column density, and NH_3_ rotational temperature.
1302. Radio and Infrared observations of EROs
ID:
ivo://CDS.VizieR/J/ApJ/581/844
Title:
Radio and Infrared observations of EROs
Short Name:
J/ApJ/581/844
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results from a sensitive multiwavelength analysis of the properties of extremely red objects (EROs). Our analysis employs deep RIzJHK photometry of an 8.5'x8.5' region to select a sample of 68 EROs with (R-K)>=5.3 and brighter than K=20.5 (5{sigma}). We combine this photometric data set with an extremely deep 1.4GHz radio map of the field obtained from the VLA. This map reaches a 1{sigma} limiting flux density of 3.5{mu}Jy , making it the deepest 1.4GHz map taken, and is sensitive enough to detect an active galaxy with L1.4>~10^23^W/Hz at z>1.
1303. Radio and IR counterparts of BLAST sources in CDFS
ID:
ivo://CDS.VizieR/J/ApJ/703/285
Title:
Radio and IR counterparts of BLAST sources in CDFS
Short Name:
J/ApJ/703/285
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have identified radio and/or mid-infrared counterparts to 198 out of 350 sources detected at >=5{sigma} over ~9deg^2^ centered on the Chandra Deep Field South by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) at 250, 350, and 500um. We have matched 114 of these counterparts to optical sources with previously derived photometric redshifts and fitted spectral energy distributions to the BLAST fluxes and fluxes at 70 and 160um acquired with the Spitzer Space Telescope. In this way, we have constrained dust temperatures, total far-infrared/submillimeter luminosities, and star formation rates for each source. Our findings show that, on average, the BLAST sources lie at significantly lower redshifts and have significantly lower rest-frame dust temperatures compared to submillimeter sources detected in surveys conducted at 850um. We demonstrate that an apparent increase in dust temperature with redshift in our sample arises as a result of selection effects. Finally, we provide the full multiwavelength catalog of >=5{sigma} BLAST sources contained within the complete ~9deg^2^ survey area.
1304. Radio and K-band obs. of Ultra-Steep sources
ID:
ivo://CDS.VizieR/J/MNRAS/347/837
Title:
Radio and K-band obs. of Ultra-Steep sources
Short Name:
J/MNRAS/347/837
Date:
21 Oct 2021
Publisher:
CDS
Description:
A sample of 76 ultra-steep spectrum (USS) radio sources is defined from the 843-MHz Sydney University Molonglo Sky Survey (SUMSS) and 1.4-GHz NRAO VLA Sky Survey (NVSS) radio surveys with spectral index {alpha}<-1.3 and S(1.4GHz)>15mJy; 71 of these sources without bright optical or near-infrared counterparts at 1.385GHz were observed with the Australia Telescope Compact Array (ATCA), providing 5arcsec resolution images and subarcsec positional accuracy. To identify their host galaxies, near-infrared K-band images were obtained with IRIS2 at the AAT and SofI at the NTT; 92% of the USS sources could be identified down to K~20.5. 142 FITS files containing the radio maps and the K-band images are included in the fits subdirectory.
1305. Radio and optical properties of QSOs
ID:
ivo://CDS.VizieR/J/AJ/141/182
Title:
Radio and optical properties of QSOs
Short Name:
J/AJ/141/182
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the largest homogeneous quasar sample with high-quality optical spectra and robust radio morphology classifications assembled to date, we investigate relationships between radio and optical properties with unprecedented statistical power. The sample consists of 4714 radio quasars from FIRST with S_20_>=2mJy and with spectra from the Sloan Digital Sky Survey (SDSS). Radio morphology classes include core-only (core), core-lobe (lobe), core-jet (jet), lobe-core-lobe (triple), and double-lobe.
1306. Radio and UV spectra of HVC toward the MC
ID:
ivo://CDS.VizieR/J/ApJ/702/940
Title:
Radio and UV spectra of HVC toward the MC
Short Name:
J/ApJ/702/940
Date:
21 Oct 2021
Publisher:
CDS
Description:
In the spectra of 139 early-type Large Magellanic Cloud (LMC) stars observed with Far Ultraviolet Spectroscopic Explorer and with deep radio Parkes HI 21cm observations along with those stars, we search for and analyze the absorption and emission from high-velocity gas at +90<={nu}_LSR_<=+175km/s. The HI column density of the high-velocity clouds (HVCs) along these sightlines ranges from <1018.4 to 1019.2cm^-2^. The incidence of the HVC metal absorption is 70%, significantly higher than the HI emission occurrence of 32%. We find that the mean metallicity of the HVC is [OI/HI]=-0.51+/-^0.12^_0.16_. This is the first example of a large (>10^6^M_{sun}_) HVC complex that is linked to stellar feedback occurring in a dwarf spiral galaxy.
1307. Radio and X-ray-emitting broad-line AGNs
ID:
ivo://CDS.VizieR/J/ApJ/645/890
Title:
Radio and X-ray-emitting broad-line AGNs
Short Name:
J/ApJ/645/890
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derived the black hole fundamental plane relationship between the 1.4GHz radio luminosity (Lr), 0.1-2.4keV X-ray luminosity (LX), and black hole mass (M) from a uniform broad-line SDSS AGN sample including both radio-loud and radio-quiet X-ray-emitting sources. We found in our sample that the fundamental plane relation has a very weak dependence on the black hole mass, and a tight correlation also exists between the Eddington-luminosity-scaled X-ray and radio luminosities for the radio-quiet subsample. In addition, we noticed that the radio-quiet and radio-loud AGNs have different power-law slopes in the radio-X-ray nonlinear relationship. The radio-loud sample displays a slope of 1.39, which seems consistent with the jet-dominated X-ray model. However, it may also be partly due to the relativistic beaming effect. For the radio-quiet sample the slope of the radio-X-ray relationship is about 0.85, which is possibly consistent with the theoretical prediction from the accretion-flow-dominated X-ray model. We briefly discuss the reason why our derived relationship is different from some previous works and expect the future spectral studies in radio and X-ray bands on individual sources in our sample to confirm our result.
1308. Radio and X-ray observations of Aql X-1
ID:
ivo://CDS.VizieR/J/ApJ/716/L109
Title:
Radio and X-ray observations of Aql X-1
Short Name:
J/ApJ/716/L109
Date:
21 Oct 2021
Publisher:
CDS
Description:
The 2009 November outburst of the neutron star X-ray binary Aquila X-1 (Aql X-1) was observed with unprecedented radio coverage and simultaneous pointed X-ray observations, tracing the radio emission around the full X-ray hysteresis loop of the outburst for the first time. We use these data to discuss the disk-jet coupling, finding the radio emission to be consistent with being triggered at state transitions, both from the hard to the soft spectral state and vice versa. Our data appear to confirm previous suggestions of radio quenching in the soft state above a threshold X-ray luminosity of ~10% of the Eddington luminosity. We also present the first detections of Aql X-1 with very long baseline interferometry, showing that any extended emission is relatively diffuse and consistent with steady jets rather than arising from discrete, compact knots. In all cases where multi-frequency data were available, the source radio spectrum is consistent with being flat or slightly inverted, suggesting that the internal shock mechanism that is believed to produce optically thin transient radio ejecta in black hole X-ray binaries is not active in Aql X-1.
1309. RadioAstron. III. S5 0716+71 at uarcsec res.
ID:
ivo://CDS.VizieR/J/ApJ/893/68
Title:
RadioAstron. III. S5 0716+71 at uarcsec res.
Short Name:
J/ApJ/893/68
Date:
03 Dec 2021 00:43:28
Publisher:
CDS
Description:
We present RadioAstron Space VLBI imaging observations of the BL Lac object S5 0716+71 made on 2015 January 3-4 at a frequency of 22GHz (wavelength {lambda}=1.3cm). The observations were made in the framework of the AGN Polarization Key Science Program. The source was detected on projected space-ground baselines up to 70833km (5.6 Earth diameters) for both parallel-hand and cross-hand interferometric visibilities. We have used these detections to obtain a full-polarimetric image of the blazar at an unprecedented angular resolution of 24{mu}as, the highest for this source to date. This enabled us to estimate the size of the radio core to be <12x5{mu}as and to reveal a complex structure and a significant curvature of the blazar jet in the inner 100{mu}as, which is an indication that the jet viewing angle lies inside the opening angle of the jet conical outflow. Fairly highly (15%) linearly polarized emission is detected in a jet region 19{mu}as in size, located 58{mu}as downstream from the core. The highest brightness temperature in the source frame is estimated to be >2.2x10^13^K for the blazar core. This implies that the inverse-Compton limit must be violated in the rest frame of the source, even for the largest Doppler factor {delta}~25 reported for 0716+714.
1310. Radio catalogue of Galactic HII regions
ID:
ivo://CDS.VizieR/J/A+A/623/A105
Title:
Radio catalogue of Galactic HII regions
Short Name:
J/A+A/623/A105
Date:
21 Oct 2021
Publisher:
CDS
Description:
Large-scale radio continuum surveys provide data to get insights into the physical properties of radio sources. HII regions are prominent radio sources produced by thermal emission of ionised gas around young massive stars. We identify and analyse HII regions in the Sino-German {lambda}6cm polarisation survey of the Galactic plane. Objects with flat radio continuum spectra together with infrared and/or H{alpha} emission were identified to be HII regions. For HII regions with small apparent sizes, we cross-matched the {lambda}6cm small-diameter source catalogue with the radio HII region catalogue compiled by Paladini and the infrared HII region catalogue based on the WISE data. Effelsberg {lambda}21cm and {lambda}11cm continuum survey data were used to determine source spectra. High angular resolution data from the Canadian Galactic Plane Survey and the NVSS were used to solve the confusion when low angular resolution observations are not sufficient. Extended HII regions were identified by overlaying the Paladini and the WISE HII regions onto the {lambda}6cm survey images for coincidences by eye. The TT-plot method was employed for spectral index verification. 401 HII regions were identified and their flux densities were determined with the Sino-German {lambda}6cm survey data. In the surveyed area, 76 pairs of sources are found to be duplicated in the Paladini HII region catalogue mainly due to the non-distinction of previous observations with different angular resolutions, and 78 objects in their catalogue are misclassified as HII regions, being actually planetary nebulae, supernova remnants or extragalactic sources that have steep spectra. More than 30 HII regions and HII region candidates from our {lambda}6cm survey data, especially extended ones, do not have counterparts in the WISE HII region catalogue, among which 9 are identified for the first time. Our results imply that some more Galactic HII regions still await to be discovered and the combination of multi-domain observations is important for HII region identification. Based on the newly derived radio continuum spectra and the evidence of infrared emission, the previously identified SNRs G11.1-1.0, G20.4+0.1 and G16.4-0.5 are believed to be HII regions.