- ID:
- ivo://CDS.VizieR/VIII/78
- Title:
- Sydney University Molonglo Sky Survey (SUMSS)
- Short Name:
- VIII/78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Sydney University Molonglo Sky Survey (SUMSS) is being carried out at 843MHz with the Molonglo Observatory Synthesis Telescope (MOST) in its upgraded wide-field capability. The survey consists of 4.3x4.3{deg} mosaic images with 45x45''cosec{delta} resolution, covering 8000 square degrees from -30 degrees declination southwards. The survey resolution and sensitivity (1-sigma noise limit 1mJy) are well-matched to the NRAO VLA Sky Survey (NVSS) so that together NVSS and SUMSS will provide a complete survey of the radio sky. The version 1.7 (01-Jun-2006) of the catalogue consists of 205676 radio sources made by fitting elliptical gaussians in 671 SUMSS mosaics to a limiting peak brightness of 6mJy/beam at declination <-50{deg}, and 10mJy/beam at declination >-50{deg}. Positional accuracies are 1-2'' for sources with S_p_>=20mJy/beam, and are always better than 10''. The internal flux density scale is accurate to 3%. Image artefacts have been classified using a decision tree, which correctly identifies and rejects spurious sources in over 96% of cases. See the SUMSS site at http://www.astrop.physics.usyd.edu.au/sumsscat/ for details about all versions of the SUMSS, and an access to the mosaic images.
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Search Results
- ID:
- ivo://CDS.VizieR/VIII/81B
- Title:
- Sydney University Molonglo Sky Survey (SUMSS V2.1)
- Short Name:
- VIII/81B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Sydney University Molonglo Sky Survey (SUMSS) is carried out at 843MHz with the Molonglo Observatory Synthesis Telescope (MOST) in its upgraded wide-field capability. The survey consists of 4.3x4.3{deg} mosaic images with 45x45''cosec{delta} resolution, covering 8000 square degrees from -30 degrees declination southwards with |b|>10{deg}. The survey resolution and sensitivity (1-sigma noise limit 1mJy) are well-matched to the NRAO VLA Sky Survey (NVSS) so that together NVSS and SUMSS provide a complete survey of the radio sky. The version 2.0 (08-Aug-2007) of the catalogue consists of 210412 radio sources made by fitting elliptical gaussians in 633 SUMSS mosaics to a limiting peak brightness of 6mJy/beam at declination <-50{deg}, and 10mJy/beam at declination >-50{deg}. Positional accuracies are 1-2'' for sources with S_p_>=20mJy/beam, and are always better than 10''. The internal flux density scale is accurate to 3%. Image artefacts have been classified using a decision tree, which correctly identifies and rejects spurious sources in over 96% of cases. See the SUMSS site at http://www.astrop.physics.usyd.edu.au/sumsscat/ for details about all versions of the SUMSS, and an access to the mosaic images. The version 2.1 (from 2008-03-11) corrects a bug in 2.0 in which some bright (S>500 mJy) sources were missing from the catalogue.
- ID:
- ivo://CDS.VizieR/J/A+A/595/A94
- Title:
- Temperature structures in Galactic center clouds
- Short Name:
- J/A+A/595/A94
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Central Molecular Zone (CMZ) at the center of our Galaxy is the best template to study star formation processes under extreme conditions, similar to those in high-redshift galaxies. We observed on-the-fly maps of para-H_2_CO transitions at 218GHz and 291GHz with the Atacama Pathfinder Experiment (APEX) telescope towards seven Galactic center clouds. From the temperature-sensitive integrated intensity line ratios of H_2_CO(3_21_-2_20_)/H_2_CO(3_03_-2_02_) and H_2_CO(4_22_-3_21_)/H_2_CO(4_04_-3_03_) in combination with radiative transfer models, we produce gas temperature maps of our targets. Our targets have a complex velocity structure that requires a careful disentanglement of the different components. We produce temperature maps for each of the velocity components and show that the temperatures of the components differ, revealing temperature gradients in the clouds.
- ID:
- ivo://CDS.VizieR/J/A+A/608/A68
- Title:
- TeV/non-TeV BL Lacs multi-lambda fluxes
- Short Name:
- J/A+A/608/A68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have collected the most complete multi-wavelength (6.0-6.0E^-18^cm) dataset of very high energy (VHE) gamma-ray emitting (TeV) BL Lacs, which are the most numerous extragalactic VHE sources. Using significant correlations between different bands, we aim to identify the best TeV BL Lac candidates that can be discovered by the current and next generation of imaging air Cherenkovtelescopes. We formed five datasets from lower energy data, i.e. radio, mid-infrared, optical, X-rays, and GeV gamma-ray, and five VHE gamma-ray datasets to perform a correlation study between different bands and to construct the prediction method. The low energy datasets were averaged for individual sources, while the VHE gamma-ray data were divided into subsets according to the flux state of the source. We then looked for significant correlations and determined their best-fit parameters. Using the best-fit parameters we predicted the level of VHE gamma-ray flux for a sample of 182 BL Lacs, which have not been detected at TeV energies. We identified the most promising TeV BL Lac candidates based on the predicted VHE gamma-ray flux for each source. We found 14 significant correlations between radio, mid-infrared, optical, gamma-ray, and VHE gamma-ray bands. The correlation between optical and VHE gamma-ray luminosity is established for the first time. We attribute this to the more complete sample and more accurate handling of host galaxy flux in our work. We found nine BL Lac candidates whose predicted VHE gamma-ray flux is high enough for detection in less than 25 hours with current imaging air Cherenkov telescopes.
- ID:
- ivo://CDS.VizieR/VIII/42
- Title:
- Texas Survey of radio sources at 365MHz
- Short Name:
- VIII/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Texas Survey of discrete radio sources between -35.5deg and 71.5deg declination (B1950), which was carried out at 365MHz with the Texas Interferometer during 1974-1983. The Survey lists accurate positions with internal errors of about an arcsecond, flux densities which for strong point sources have internal errors of about 1% and total errors of about 5%, simple structure models and indications of spectrum and variability for 66841 sources. Results of comparisons with other data are presented, and show that the Survey is 90% complete at 0.4Jy and 80% complete at 0.25Jy, is nearly free from spurious sources, and has a lobeshift incidence which is reasonably described by quality flags associated with each source.
- ID:
- ivo://CDS.VizieR/VIII/87
- Title:
- The Allen Telescope Array 20cm Survey (ATATS). I.
- Short Name:
- VIII/87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Allen Telescope Array Twenty-centimeter Survey (ATATS), a multi-epoch (12 visits), 690deg^2^ radio image and catalog at 1.4GHz. The survey is designed to detect rare, very bright transients as well as to verify the capabilities of the ATA to form large mosaics. The combined image using data from all 12 ATATS epochs has rms noise {sigma}=3.94mJy/beam and dynamic range 180, with a circular beam of 150" FWHM. It contains 4408 sources to a limiting sensitivity of 5{sigma}=20mJy/beam. We compare the catalog generated from this 12 epoch combined image to the NRAO VLA Sky Survey (NVSS), a legacy survey at the same frequency, and find that we can measure source positions to better than ~20". For sources above the ATATS completeness limit, the median flux density is 97% of the median value for matched NVSS sources, indicative of an accurate overall flux calibration. We examine the effects of source confusion due to the effects of differing resolution between ATATS and NVSS on our ability to compare flux densities. We detect no transients at flux densities greater than 40mJy in comparison with NVSS and place a 2{sigma} upper limit of 0.004deg^-2^ on the transient rate for such sources. These results suggest that the >~1Jy transients reported by Matsumara et al. may not be true transients, but rather variable sources at their flux density threshold.
- ID:
- ivo://CDS.VizieR/J/ApJS/244/25
- Title:
- The BAaDE SiO maser survey at 86GHz with ALMA
- Short Name:
- J/ApJS/244/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the first 1432 sources observed using the Atacama Large Millimeter/submillimeter Array, from the Bulge Asymmetries and Dynamical Evolution survey, which aims to obtain tens of thousands of line-of-sight velocities from SiO masers in Asymptotic Giant Branch (AGB) stars in the Milky Way. A 71% detection rate of 86GHz SiO masers is obtained from the infrared color-selected sample and increases to 80% when considering the likely oxygen-rich stars using Midcourse Space Experiment colors isolated in a region where [D]-[E]<=1.38. Based on Galactic distributions, the presence of extended CS emission, and likely kinematic associations, the population of sources with [D]-[E]>1.38 probably consists of young stellar objects, or alternatively, of planetary nebulae. For the SiO detections, we examined whether individual SiO transitions provide comparable stellar line-of-sight velocities and found that any SiO transition is suitable for determining a stellar AGB line-of-sight velocity. Finally, we discuss the relative SiO detection rates and line strengths in the context of current pumping models.
- ID:
- ivo://CDS.VizieR/J/ApJS/209/2
- Title:
- The BGPS. X. Dense molecular gas
- Short Name:
- J/ApJS/209/2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Bolocam Galactic Plane Survey (BGPS) is a 1.1 mm continuum survey of dense clumps of dust throughout the Galaxy covering 170deg^2^. We present spectroscopic observations using the Heinrich Hertz Submillimeter Telescope of the dense gas tracers, HCO^+^ and N_2_H^+^3-2, for all 6194 sources in the BGPS v1.0.1 catalog between 7.5{deg}<=l<=194{deg}. This is the largest targeted spectroscopic survey of dense molecular gas in the Milky Way to date. We find unique velocities for 3126 (50.5%) of the BGPS v1.0.1 sources observed. Strong N_2_H^+^ 3-2 emission (T_mb_>0.5K) without HCO^+^ 3-2 emission does not occur in this catalog. We characterize the properties of the dense molecular gas emission toward the entire sample. HCO^+^ is very sub-thermally populated and the 3-2 transitions are optically thick toward most BGPS clumps. The median observed line width is 3.3 km/s consistent with supersonic turbulence within BGPS clumps. We find strong correlations between dense molecular gas integrated intensities and 1.1 mm peak flux and the gas kinetic temperature derived from previously published NH_3_observations. These intensity correlations are driven by the sensitivity of the 3-2 transitions to excitation conditions rather than by variations in molecular column density or abundance. We identify a subset of 113 sources with stronger N_2_H^+^ than HCO^+^ integrated intensity, but we find no correlations between the N_2_H^+^/HCO^+^ ratio and 1.1 mm continuum flux density, gas kinetic temperature, or line width. Self-absorbed profiles are rare (1.3%).
- ID:
- ivo://CDS.VizieR/J/ApJS/188/123
- Title:
- The Bolocam Galactic Plane Survey. II.
- Short Name:
- J/ApJS/188/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 8358 sources extracted from images produced by the Bolocam Galactic Plane Survey (BGPS). The BGPS is a survey of the millimeter dust continuum emission from the northern Galactic plane. The catalog sources are extracted using a custom algorithm, Bolocat, which was designed specifically to identify and characterize objects in the large-area maps generated from the Bolocam instrument. The catalog products are designed to facilitate follow-up observations of these relatively unstudied objects. The catalog is 98% complete from 0.4Jy to 60Jy over all object sizes for which the survey is sensitive (<3.5'). We find that the sources extracted can best be described as molecular clumps-large dense regions in molecular clouds linked to cluster formation. We find that the flux density distribution of sources follows a power law with dN/dS{prop.to}S^-2.4+/-0.1^ and that the mean Galactic latitude for sources is significantly below the midplane: <b>=(-0.095+/-0.001{deg}).
- ID:
- ivo://CDS.VizieR/VIII/1A
- Title:
- The 3C and 3CR Catalogues
- Short Name:
- VIII/1A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 3C Catalog is the result of observations with the Cambridge four-element interferometer at a frequency of 159MHz, and contains 471 sources between declinations -22 and +71degrees, with a flux density larger than 8Jy. The Revised version of the 3C (3CR) is based on new observations at a frequency of 178MHz, and represents a survey of all sources North of -05degrees with a flux density brighter than 9Jy, except in the areas near the ridge of galactic emission. The original numbering system has been preserved.
