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During the summer of 1994 it is expected that an improved A&G unit will
be installed and commissioned at UES. The features that will be offered by
the new unit are detailed below:
REQUIREMENTS FOR UES FIBRES ENHANCEMENT
- Only 2 fibres bundles will be required, one for slit viewing and one
for off-axis guiding. It will be possible to view the fields
from both fibres on the CCD simultaneously.
- The enhanced optical/fibre system will work with
the existing autoguider head.
- Each fibre will have a field of view of arcsecs
- Image scale on CCD will be in range 0.15 to 0.2 arcsec/pixel
- Overall improvement in sensitivity of off-axis channel
will be at least a factor of 20, with a factor of about 10 or possibly
more from the fibre/optical components, and a factor of 2 from
the autoguider CCD. This should take the limiting magnitude to
about 17th in V.
- Overall improvement in sensitivity of slit-view channel
to a similar limiting magnitude (ie. to about 17th magnitude
including the CCD improvement).
- Wavelength coverage will be 400-700 nm.
- It will be possible to adjust the focus for each fibre
Additional related enhancements that will be provided are:
- The range of ND filters will be re-specified.
- The TCS software will be modified to cope with differential refraction
- A thinned CCD will be provided in the autoguider head. This will
almost certainly be an EEV device, to minimise the changes required to
the existing autoguider system.
- It will be possible to guide using either fibre
- The autoguider software will allow read out and
display of both windows, whilst guiding on either.