The Wide-Field Survey
with the INT Wide-Field Camera
The
INT Wide Field Survey (WFS) is using the Wide Field Camera (~0.3 deg2
) on the 2.5m Isaac Newton Telescope
(INT). The project was initiated in August 1998 and is expected to
have a duration ofat least five years. The WFS is an umbrella for competitively
judged science programmes which were assessed on the usual criteria plus
the wider worth of the data set and the management competence of the proposing
teams.
Multicolour data is being obtained over
200+ square degrees to a typical depth of ~25 mag (u' through z'). Importantly,
the data is publically accessible by the UK and NL communities from day
one, with access to the rest of the world after one year. The preliminary
processing and calibration (up to object catalogue generation) is the responsibility
of the WFS project.
In recent years a number of major survey
programmes covering a variety of wavelengths have been initiated. The 2Mass
project is covering the entire sky at a resolution of 4 arcsec in the JHK
bands. The Sloan Sky Survey (SDSS) will cover significant areas of the
Northern Hemisphere. These wide area surveys are having a significant impact,
both as target selectors for 8 m class telescopes and for inherent survey
science programmes. The aim of the WFS is to provide deeper data than the
SDSS, but still cover significant targeted coverage, typically of fields
being observed by facilities at other frequencies.
The WFC comprises 4 CCD detectors giving
a total of almost 35 million pixels per image. Each image is read and stored
in less than 1 minute and its size is 72 Megabytes. Thanks to the upgraded
observing system, the INT can observe without human intervention for several
hours and shorten the overheads. Typically 6 Gigabytes of data is obtained
each night. This is locally pre-processed using pipeline software. To support
this, the ING Data Management System has been developed. This includes
2 DVD-R libraries giving a local on-line storage capacity of 6 TB. Later
the data is sent to the Cambridge Survey Unit to give later access to UK
and NL based researchers through an on-line archive.
More information:
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