- ID:
- ivo://CDS.VizieR/J/AJ/131/2859
- Title:
- Extragalactic First Look Survey: 24{mu}m data
- Short Name:
- J/AJ/131/2859
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the reduction of the 24{mu}m data obtained during the first cosmological survey performed by the Spitzer Space Telescope. Images of a region of sky at moderately high Galactic latitude (l=88.3{deg}, b=+34.9{deg}) were obtained on 2003 December 9-11. The survey consists of a shallow observation of 2.5x2{deg}^2^ centered at 17:18 +59:30 (main survey) and a deeper observation of 1{deg}x0.5{deg} centered at 17:17 +59:45 (verification survey). Issues with the reduction of the 24{mu}m MIPS data are discussed and solutions to attenuate instrumental effects are proposed and applied to the data. Approximately 17000 sources are extracted with a signal-to-noise ratio (S/N) greater than 5. The photometry of the point sources is evaluated through point-spread function (PSF) fitting using an empirical PSF derived from the data. Aperture corrections and the absolute calibration have been checked using stars in the field. Astrometric and photometric errors depend on the S/N of the source varying between 0.35"-1" and 5%-15%, respectively, for sources detected at 20-5{sigma}. The fluxes of the 123 extended sources have been estimated through aperture photometry. The extended sources cover less than 0.3% of the total area of the survey. Based on simulations, the main and verification surveys are 50% complete at 0.3 and 0.15mJy, respectively. Counterparts have been searched for in optical and radio catalogs.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/694/222
- Title:
- Extragalactic point sources in WMAP 5-yr maps
- Short Name:
- J/ApJ/694/222
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an extragalactic point source search using the five-year Wilkinson Microwave Anisotropy Probe (WMAP) 41, 61, and 94GHz (Q, V, and W bands) temperature maps. This work is an extension of our designing and applying a cosmic microwave background (CMB)-free technique to extract point sources in the WMAP maps. Specifically, we have formed an internal linear combination map of the three-band maps, with the weights chosen to remove the CMB anisotropy signal as well as to favor the selection of flat-spectrum sources. We have also constructed a filter to recover the true point source flux distribution on the sky. A total of 381 sources are found in our study at the >5{sigma} level outside the WMAP point source detection mask, among which 89 are "new" (i.e., not present in the WMAP catalogs). Source fluxes have been calculated and corrected for the Eddington bias. We have solidly identified 367 (96.3%) of our sources, the 1{sigma} positional uncertainty of which is 2'. The 14 unidentified sources could be either extended radio structure or obscured by Galactic emission. We have also applied the same detection approach to simulated maps, which yielded 364+/-21 detections on average. The recovered source distribution N(>S) agrees well with the simulation input, which proves the reliability of this method.
- ID:
- ivo://CDS.VizieR/J/ApJ/681/747
- Title:
- Extragalactic point-source WMAP catalog
- Short Name:
- J/ApJ/681/747
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of an extragalactic point-source search using the 61 and 94GHz (V- and W-band) temperature maps from the Wilkinson Microwave Anisotropy Probe (WMAP). Applying a method that cancels the "noise" due to the CMB anisotropy signal, we find in the |b|>10{deg} region 31 sources in the first-year maps and 64 sources in the three-year co-added maps at a 5{sigma} level. The 1{sigma} position uncertainties are 1.6' and 1.4', respectively. The increased detections and improved positional accuracy are expected from the higher signal-to-noise ratio of the WMAP three-year data. All sources detected in the first-year maps are repeatedly detected in the three-year maps, which is a strong indication of the consistency of this method. Of all the sources, 97% are identified with either the WMAP three-year source catalog or plausible extrapolations of lower frequency data, which indicates that our method is also reliable. The two unidentified sources have been recently confirmed to be false detections, using the WMAP five-year data. We derive the source count distribution at the WMAP V band by combining our verified detections with sources from the WMAP three-year catalog. If we assume that the effect of source clustering is negligible, the contribution to the power spectrum from faint sources below 0.75Jy is estimated to be (2.4+/-0.8)x10^-3^uK^2^sr for the V band, which implies a source correction amplitude of A=0.012+/-0.004uK^2^sr.
- ID:
- ivo://CDS.VizieR/J/MNRAS/371/898
- Title:
- Extragalactic radio sources selected at 20GHz
- Short Name:
- J/MNRAS/371/898
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present some first results on the variability, polarization and general properties of radio sources selected at 20GHz, the highest frequency at which a sensitive radio survey has been carried out over a large area of sky. Sources with flux densities above 100mJy in the Australia Telescope Compact Array 20GHz pilot survey at declination 60{deg} to 70{deg} were observed at up to three epochs during 2002-04, including near-simultaneous measurements at 5, 8 and 18GHz in 2003. Of the 173 sources detected, 65 per cent are candidate QSOs or BL Lac objects, 20 per cent galaxies and 15 per cent faint (bJ>22mag) optical objects or blank fields.
- ID:
- ivo://CDS.VizieR/J/ApJ/801/143
- Title:
- Extrasolar Kuiper belts from Herschel
- Short Name:
- J/ApJ/801/143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The study of the planet-debris disk connection can shed light on the formation and evolution of planetary systems and may help "predict" the presence of planets around stars with certain disk characteristics. In preliminary analyses of subsamples of the Herschel DEBRIS and DUNES surveys, Wyatt et al. (2012MNRAS.424.1206W) and Marshall et al. (2014A&A...565A..15M) identified a tentative correlation between debris and the presence of low-mass planets. Here we use the cleanest possible sample out of these Herschel surveys to assess the presence of such a correlation, discarding stars without known ages, with ages <1Gyr, and with binary companions <100AU to rule out possible correlations due to effects other than planet presence. In our resulting subsample of 204 FGK stars, we do not find evidence that debris disks are more common or more dusty around stars harboring high-mass or low-mass planets compared to a control sample without identified planets.
- ID:
- ivo://CDS.VizieR/J/ApJS/153/119
- Title:
- Faint blue objects at high galactic latitude
- Short Name:
- J/ApJS/153/119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The US (UV-excess Starlike) survey has cataloged 3987 objects in 7 high Galactic latitude fields according to their optical colors, magnitudes, and morphologies using photographic techniques. This paper analyzes the effectiveness of the survey at producing finding lists for complete samples of hot stars and quasars that exhibit blue and/or ultraviolet excess (B-UVX) relative to the colors of halo F and G subdwarf stars. A table of 599 spectroscopic identifications summarizes the spectroscopic coverage of the US objects that has been accomplished to date.
527. Faintest stars
- ID:
- ivo://CDS.VizieR/J/ApJ/414/279
- Title:
- Faintest stars
- Short Name:
- J/ApJ/414/279
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present infrared K-band photometry of complete samples of VLM candidates constructed from IIIaF and IVN plates in 10 fields taken as part of the POSSII and UKSRC surveys. Using the I-K colors constructed for these stars we estimate a bolometric luminosity function which extends to MBol=13.75. We find significant evidence for a luminosity function decreasing toward these luminosities.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/4244
- Title:
- Faint radio source population at 15.7GHz
- Short Name:
- J/MNRAS/453/4244
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A complete, flux density limited sample of 96 faint (>0.5mJy) radio sources is selected from the 10C survey at 15.7GHz in the Lockman Hole. We have matched this sample to a range of multi-wavelength catalogues, including Spitzer Extragalactic Representative Volume Survey, Spitzer Wide-area Infrared Extragalactic survey, United Kingdom Infrared Telescope Infrared Deep Sky Survey and optical data; multi-wavelength counterparts are found for 80 of the 96 sources and spectroscopic redshifts are available for 24 sources. Photometric redshifts are estimated for the sources with multi-wavelength data available; the median redshift of the sample is 0.91 with an interquartile range of 0.84. Radio-to-optical ratios show that at least 94 per cent of the sample are radio loud, indicating that the 10C sample is dominated by radio galaxies. This is in contrast to samples selected at lower frequencies, where radio-quiet AGN and star-forming galaxies are present in significant numbers at these flux density levels. All six radio-quiet sources have rising radio spectra, suggesting that they are dominated by AGN emission. These results confirm the conclusions of that the faint, flat-spectrum sources which are found to dominate the 10C sample below ~1mJy are the cores of radio galaxies. The properties of the 10C sample are compared to the Square Kilometre Array Design Studies Simulated Skies; a population of low-redshift star-forming galaxies predicted by the simulation is not found in the observed sample.
- ID:
- ivo://CDS.VizieR/J/ApJ/875/80
- Title:
- Faint radio sources in GOODS-N and -S. I. VLA 5GHz
- Short Name:
- J/ApJ/875/80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results from the deep and wide 5GHz radio observations of the Great Observatories Origins Deep Survey (GOODS)-North ({sigma}=3.5{mu}Jy/beam, synthesized beam size {theta}=1.47"x1.42", and 52 sources over 109arcmin^2^) and GOODS-South ({sigma}=3.0{mu}Jy/beam, {theta}=0.98"x0.45", and 88 sources over 190arcmin^2^) fields using the Karl G. Jansky Very Large Array. We derive radio spectral indices {alpha} between 1.4 and 5GHz using the beam-matched images and show that the overall spectral index distribution is broad even when the measured noise and flux bias are considered. We also find a clustering of faint radio sources around {alpha}=0.8, but only within S_5GHz_<150{mu}Jy. We demonstrate that the correct radio spectral index is important for deriving accurate rest-frame radio power and analyzing the radio-FIR correlation, and adopting a single value of {alpha}=0.8 leads to a significant scatter and a strong bias in the analysis of the radio-FIR correlation, resulting from the broad and asymmetric spectral index distribution. When characterized by specific star formation rates, the starburst population (58%) dominates the 5GHz radio source population, and the quiescent galaxy population (30%) follows a distinct trend in spectral index distribution and the radio-FIR correlation. Lastly, we offer suggestions on sensitivity and angular resolution for future ultra-deep surveys designed to trace the cosmic history of star formation and AGN activity using radio continuum as a probe.
- ID:
- ivo://CDS.VizieR/J/A+AS/104/1
- Title:
- Faint ring-shaped galaxies near South Pole
- Short Name:
- J/A+AS/104/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A list of probable ring galaxies with a limiting magnitude of 17.5 has been prepared based on visual inspection of the film copies of the J SRC/ESO survey. About 88% of the sample of 125 selected objects seem to be new, hitherto unrecognized as ring galaxies. The candidate objects have been classified following the ring structure and the nucleus appearance.
