Kieran A. Cleary

Publications (3)14.7 Total impact

• Article: A 33‐GHz Very Small Array survey of the Galactic plane from ℓ= 27° to 46°

  Magdolna Todorović, Rodney D. Davies, Clive Dickinson, Richard J. Davis, Kieran A. Cleary, Ricardo Génova-Santos, Keith J. B. Grainge, Yaser A. Hafez, Michael P. Hobson, Michael E. Jones, Katy Lancaster, Rafael Rebolo, Wolfgang Reich, José Alberto Rubiño-Martín, Richard D. E. Saunders, Richard S. Savage, Paul F. Scott, Anže Slosar, Angela C. Taylor, Robert A. Watson
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  ABSTRACT: The Very Small Array (VSA) has been used to survey the ℓ∼ 27° to region of the Galactic plane at a resolution of 13 arcmin. This ℓ-range covers a section through the Local, Sagittarius and the Cetus spiral arms. The survey consists of 44 pointings of the VSA, each with an rms sensitivity of ∼90 mJy beam−1. These data are combined in a mosaic to produce a map of the area. The majority of the sources within the map are H ii regions.The main aim of the programme was to investigate the anomalous radio emission from the warm dust in individual H ii regions of the survey. This programme required making a spectrum extending from GHz frequencies to the far-infrared (FIR) IRAS frequencies for each of nine strong sources selected to lie in unconfused areas. It was necessary to process each of the frequency maps with the same u, v coverage as was used for the VSA 33 GHz observations. The additional radio data were at 1.4, 2.7, 4.85, 8.35, 10.55, 14.35 and 94 GHz in addition to the 100, 60, 25 and 12 μm IRAS bands. From each spectrum the free–free, thermal dust and anomalous dust emission were determined for each H ii region. The mean ratio of 33 GHz anomalous flux density to FIR 100 μm flux density for the nine selected H ii regions was ΔS(33 GHz)/S(100 μm) = 1.10 ± 0.21 × 10−4. When combined with six H ii regions previously observed with the VSA and the Cosmic Background Imager, the anomalous emission from warm dust in H ii regions is detected with a 33 GHz emissivity of 4.65 ± 0.40 μK (MJy sr−1)−1 (11.5σ). This level of anomalous emission is 0.3 to 0.5 of that detected in cool dust clouds.A radio spectrum of the H ii region anomalous emission covering GHz frequencies is constructed. It has the shape expected for spinning dust composed of very small grains. The anomalous radio emission in H ii regions is on average 41 ± 10 per cent of the radio continuum at 33 GHz. Another result is that the excess (i.e. non-free–free) emission from H ii regions at 94 GHz correlates strongly with the 100 μm emission; it is also inversely correlated with the dust temperature. Both these latter results are as expected for very large grain dust emission. The anomalous emission on the other hand is expected to originate in very small spinning grains and correlates more closely with the 25 μm emission.
  Monthly Notices of the Royal Astronomical Society 06/2010; 406(3):1629 - 1643. · 4.90 Impact Factor
• Article: Erratum: Source subtraction for the extended Very Small Array and 33‐GHz source count estimates

  Kieran A. Cleary, Angela C. Taylor, Elizabeth Waldram, Richard A. Battye, Clive Dickinson, Rod D. Davies, Richard J. Davis, Ricardo Genova‐Santos, Keith Grainge, Michael E. Jones, Rüdiger Kneissl, G. G. Pooley, Rafael Rebolo, Alberto Rubiño‐Martin, Richard D.E. Saunders, Paul F. Scott, Anže Slosar, David Titterington, Robert A. Watson
  Monthly Notices of the Royal Astronomical Society 04/2008; 386(3):1759 - 1760. · 4.90 Impact Factor
• Source

  Available from: José Alberto Rubiño-Martín

  Article: Source subtraction for the extended Very Small Array and 33-GHz source count estimates

  Kieran A. Cleary, Angela C. Taylor, Elizabeth Waldram, Richard A. Battye, Clive Dickinson, Rod D. Davies, Richard J. Davis, Ricardo Genova-Santos, Keith Grainge, Michael E. Jones, Rudiger Kneissl, G. G. Pooley, Rafael Rebolo, Jose Alberto Rubino-Martin, Richard D. E. Saunders, Paul F. Scott, Anze Slosar, David Titterington, Robert A. Watson
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  ABSTRACT: We describe the source subtraction strategy and observations for the extended Very Small Array, a CMB interferometer operating at 33 GHz. A total of 453 sources were monitored at 33 GHz using a dedicated source subtraction baseline. 131 sources brighter than 20 mJy were directly subtracted from the VSA visibility data. Some characteristics of the subtracted sources, such as spectra and variability, are discussed. The 33-GHz source counts are estimated from a sample selected at 15 GHz. The selection of VSA fields in order to avoid bright sources introduces a bias into the observed counts. This bias is corrected and the resulting source count is estimated to be complete in the flux-density range 20-114 mJy. The 33-GHz source counts are used to calculate a correction to the VSA power spectrum for sources below the subtraction limit.
  Monthly Notices of the Royal Astronomical Society 01/2005; · 4.90 Impact Factor