CFHTLS Y-band WIRCam Large Program : CFHQSIR

Observing Status & Elixir Processing and Validation

Last update: Mon May 27 17:59:02 HST 2013
The CFHQSIR* survey consists in WIRCam Y-band imaging of the 171 CFHTLS Wide fields distributed over four patches across the sky. The main scientific objective of CFHQSIR is to search for quasars at redshifts ~7 (the principal investigators are J.-G. Cuby for France & C. Willott for Canada). CFHQSIR will also detect brown dwarfs and complement the CFBDSIR program. As a near IR counterpart of the CFHTLS, CFHQSIR will be of general interest to a large community of CFHTLS users.

Each WIRCam pointing (20'x20' field of view, 9 WIRCam pointings are needed to cover one single one square degree MegaCam tile) consists of 4-dithered 75 second Y-band exposures split in two 2-exposure visits separated by at least 20 days. At the end of the survey, all four CFHTLS Wide patches made from a total of 171 MegaCam pointings will lead to a sky coverage of 150 sq.deg. once the overlaps between pointings and gaps have all been accounted for. The depth of the total 5mn integration will be defined by the ~0.6" median image quality and low to medium sky background.

This collection of pages aims at tracking the progress of the CFHQSIR survey at CFHT (Large Program "P22") from the following viewpoints:

  • Raw data acquired at CFHT using the WIRCam imager through Queued Service Observing (QSO)
  • Processed and validated based on a processing using exclusively the Elixir (detrending) & Elixir-IR (sky correction) pipelines at CFHT (this will also serve as a mean of performance and processing quality comparison with the official CFHT WIRCam pipeline `I`iwi2)
  • Photometric calibration of this Y-band survey based on the CFHTLS data collection with a goal of 1% level as in the optical CFHTLS final release (2011)

* CFHQSIR stands for the Canada-France High-z quasar survey in the near-infrared, a reference to the optical survey based on the CFHTLS (CFHQS, Willott et al. 2007)