Durham University
Astronomical Instrumentation Group
Thousand Element Integral Field Unit (TEIFU)
Commissioning news
(June and Sept 1999 - 2 nights each).
TEIFU was commissioned with ELECTRA on the William Herschel
Telescope. During this short time the optical interface to both ELECTRA and
WYFFOS was achieved and the performance quantified by flatfield and standard
star observations. Early results are very encouraging with indication of
good fibre-fibre response and overall system throughput. Finally, the entire
Telescope+ELECTRA+TEIFU+WYFFOS system was tested by observing 3C237 with AO
correction. Thanks to the the entire TEIFU and ELECTRA teams plus Don
Pollaco and Frank Gribbin at the telescope.
Description
TEIFU is a new system for two-dimensional ( integral
field ) spectroscopy using adaptively-corrected images produced by
the ELECTRA (and later, NAOMI) AO systems. It will also be able to
operate in a stand-alone mode without an AO system.
The system will be mounted on an optical bench in the WHT GHRIL, fed by
the Nasmyth focus, and will feed fibres into RGO's WYFFOS fibre spectrograph.
A paper (WORD97) describing TEIFU by
Murray et al., given at the 2000 SPIE large telescope conference in
Munich.
| TEIFU parameters |
| Input from ELECTRA and/or NAOMI |
| Output to WYFFOS (f/1.2 camera) |
| Sampling (arcsec) |
0.25 |
0.13 |
| Field (arcsec) |
2 x (7.0 x 3.9) |
2 x (3.5 x 1.9) |
| Two separate fields to aid background subtraction |
| Object and sky fields movable within 80" AO field |
| IFU (only) throughput: ~60%; Filling factor: ~100% |
| Option for stand-alone operation without AO |
| Option for 0.5 arcsec sampling |
Next stages
TEIFU has now successfully commissioned with the ELECTRA. The next stage is
to modify the fore-optics for use with the NAOMI AO system which is partly
based on ELECTRA and which should be completed in 2000.
j.r.allington-smith@durham.ac.uk
21 Dec 1999