University of Hertfordshire

From the same journal

From the same journal

By the same authors


  • J.E. Drew
  • Eduardo A. González-Solares
  • Robert Greimel
  • M.J. Irwin
  • A. Küpcü Yoldaş
  • J.R. Lewis
  • Geert Barentsen
  • Jochen Eislöffel
  • Hywel J. Farnhill
  • Nicholas A. Walton
  • M. Mohr-Smith
  • Roberto Raddi
  • Stuart E. Sale
  • Nicholas J. Wright
  • Paul J. Groot
  • Michael J. Barlow
  • R.L.M. Corradi
  • Jeremy J. Drake
  • Juan Fabregat
  • David J. Frew
  • Boris T. Gänsicke
  • Christian Knigge
  • Antonio Mampaso
  • R.A.H. Morris
  • Tim J. Naylor
  • Quentin A. Parker
  • Steven Phillipps
  • Christine Ruhland
  • Danny T H Steeghs
  • Y.C. Unruh
  • Jorick S. Vink
  • Roger Wesson
  • Albert Zijlstra
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Original languageEnglish
Number of pages23
Pages (from-to)2036-2058
JournalMonthly Notices of the Royal Astronomical Society
Journal publication date21 May 2014
Early online date2 Apr 2014
Publication statusPublished - 21 May 2014


The VST Photometric Hα Survey of the Southern Galactic Plane and Bulge (VPHAS+) is surveying the southern Milky Way in u, g, r, i and Hα at ~1 arcsec angular resolution. Its footprint spans the Galactic latitude range -5o <b <+5° at all longitudes south of the celestial equator. Extensions around the Galactic Centre to Galactic latitudes ±10° bring in much of the Galactic bulge. This European Southern Observatory public survey, begun on 2011 December 28, reaches down to ~20th magnitude (10σ) and will provide single-epoch digital optical photometry for ~300 million stars. The observing strategy and data pipelining are described, and an appraisal of the segmented narrow-band Hα filter in use is presented. Using model atmospheres and library spectra, we compute main-sequence (u - g), (g - r), (r - i) and (r - Hα) stellar colours in the Vega system. We report on a preliminary validation of the photometry using test data obtained from two pointings overlapping the Sloan Digital Sky Survey. An example of the (u - g, g - r) and (r - Hα, r - i) diagrams for a full VPHAS+ survey field is given. Attention is drawn to the opportunities for studies of compact nebulae and nebular morphologies that arise from the image quality being achieved. The value of the u band as the means to identify planetary-nebula central stars is demonstrated by the discovery of the central star of NGC 2899 in survey data. Thanks to its excellent imaging performance, the VLT Survey Telescope (VST)/OmegaCam combination used by this survey is a perfect vehicle for automated searches for reddened early-type stars, and will allow the discovery and analysis of compact binaries, white dwarfs and transient sources.


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