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Below is a summary of instruments available on ING telescopes. Common
user instruments are those instruments supported by ING personnel, visitor
instruments are those which are supported by other groups but which
are regularly scheduled on ING telescopes. Future instruments refer
to those instruments which are currently funded, either as common user
or visitor instruments.
Common User Instruments
Prime focus imaging at the 4.2 WHT is available using a
2xEEV camera giving a pixel scale of 0.24 arc-seconds and a field
of view 16.2x16.2 arc-minutes. A selection of broad and narrow band
filters are available, the filter wheel being able to hold 7 filters
simultaneously.
AUX
The Auxiliary port camera at the Cassegrain focus of the 4.2m WHT has the
highest spatial resolution of any non-AO camera at the ING, its 1024x1024
TEK detector giving a pixel scale of 0.11 arc-seconds and a field of view
of 1.8x1.8 arc-minutes. This camera is permanently mounted on the WHT,
kept cold and equiped with UBVRIZ filters. It is thus ideally suited to
ToO type observations. Filter changes are allowed provided the camera
has been requested explicitly by the scheduled observer with filters different from
the default set. No filter changes are allowed for Service observations.
LIRIS
LIRIS is a near-IR imager and low resolution (R=1000 and R=3000) spectrograph
for use at the 4.2m WHT. It uses a 1024x1024 HAWAII detector array for imaging
from 0.8 to 2.5 μm. The plate scale is 0.24 arcsec/pixel yielding a 4.27 x 4.27
arcminute field of view. 12 broad and narrow band filters are available, as well as
5 different long slits. The slit wheel contains additional positions for about 6-10
multislit masks. However, due to the large complexity involved (the masks are in the
cryostat) this mode it is not available for the public community. Besides, LIRIS
offers polarimetry for both imaging and spectroscopy. A coronographic mode is
available as well.
The NAOMI adaptive-optics facility provides near-diffraction-limited
imaging at the WHT GHRIL Nasmyth focus. It
uses a 10*10-element Shack-Hartmann wavefront sensor and a 76-element
(228 degrees of freedom) segmented deformable mirror.
NAOMI is designed to deliver, under median-seeing conditions,
K-band Strehl greater than 0.25 over 50% of the sky, and
Strehl greater than 0.7 over 5% of the sky. NAOMI will operate
with natural guide stars, but has been designed for
simple upgrade to laser-guide-star operation.
NAOMI / OASIS
INGRID is the near-IR camera used at the 4.2m WHT GHRIL Nasmyth focus for NAOMI. The 1024x1024 HAWAII detector allows imaging from 0.8 to 2.5 μm. The plate scale is 0.04 arcsec/pixel, yielding a 41 x 41 arcsecond field of view. Currently z, J, H, K, and Ks filters are available, together with 8 narrowband filters. More information about INGRID is available here.
OASIS provides AO-corrected integral-field spectroscopy
of fields between 3 and 16 arcsec in diameter (0.09 - 0.4 arcsec/lenslet),
spectroscopic resolution up to 4000. At optical wavelengths, the seeing
FWHM is typically reduced by a factor of 2 (best correction so far from
0.7 to 0.2 arcsec). Guide-star requirements are as for NAOMI / INGRID,
see the NAOMI page.
NAOMI / OSCA
Note that OASIS can also be used with the AO system switched off, e.g. if no guide star is available. OASIS was formerly used at CFHT, where the comprehensive data-reduction package XOASIS was developed. A WHT version of XOASIS is now available.
OSCA is a coronographic device permanently installed between the
adaptive optics instrument
NAOMI and the infrared camera INGRID. It provides the possibility to
obscure bright objects
behind opaque masks thus enabling the detection of faint objects and
structures wich are otherwise
hidden in the PSF wings of the bright host object. OSCA consists at
present of six hard edged masks
with sizes between 0"4 and 2"0. At present it can only be used for IR
coronographic imaging with INGRID.
ISIS
ISIS is a high-efficiency, double-armed, medium-resolution spectrograph mounted at the the Cassegrain Focal station of the 4.2m WHT. The resolving power ranges from a few hundred to a few thousand with a 1 arcsecond slit. It is capable of long-slit work with up to ~4' slit length. Use of dichroic slides permit simultaneous observing to be done in both the blue and red channels, which are optimised for their respective wavelength ranges. Spectropolarimetry and imaging polarimetry are also available, as well as drift-scan mode for high-time resolution monitoring programmes. The default detectors are a thinned EEV42-type (4k*2k) device on the blue arm and a Marconi (4k*2k) on the red channel.
AF2/WYFFOS
AF2 is an automatic fibre positioner that can place up to 90
fibres within the one
degree field of the WHT prime focal plane, or 40 arcminutes unvignetted.
Reconfiguration under software control can take
up to 45 minutes for all fibres. Minimum fibre spacing is 25-30 arcsec
and currently we only offer the small fibres with 1.6 arcsec diameter.
AF2 is used in conjunction with WYFFOS with which is possible to
obtain dispersions of between 11.0 and 0.8 A/pixel with the ISIS
gratings and from 0.57 to 0.24 A/pixel with the WYFFOS echelle gratings.
WFC
The INT Wide Field camera is mounted at the prime focus(f/3) of the 2.5m INT and consists of a close packed mosaic of 4 thinned EEV 2kx4k CCDs. The CCDs have a pixel size of 13.5 microns corresponding to 0.33"/pixel. The edge to edge limit of the mosaic neglecting the ~1 arcmin inter-chip spacing is 34.2 arcmins. The readout time for the whole mosaic is around 60 seconds. Both broadband and stromgren filtersets are available, as well as a range of narrowband filters.
Visitor Instruments
INTEGRAL is an integral-field spectrograph which is used to feed WYFFOS. Up to six fibre bundles can be mounted on INTEGRAL at a given time although in the standard configuration only three are used. In this configuration, the three bundles have fibre sizes of 0.7, 1.4 and 4.0 arcseconds, and cover areas of 7.8x6.4, 16.0x12.3 and 33.6x29.4 arcseconds respectively. Resolution is determined by the fibre size but ranges from about 2.8A to approximately 40A.
SAURON
SAURON is an integral field fixed format spectrograph designed to
operate in the wavelength range 4800-6800A with a resolution of
70km/s and fields of view of 35x35 or 10x10 arcseconds. It is used
at the Cassegrain focus of the WHT.
PNS
The planetary nebula spectograph is a spectrograph optimized to detect planetary nebulae in
external galaxies and, at the same time, to measure their radial
velocities by means of the so-called counter-dispersed technique.
UltraCam
ULTRACAM is a CCD camera designed to provide imaging photometry at high
temporal resolution in three different colours simultaneously with a 5 arcminute field of view
on its three 1024x1024 CCDs (i.e. 0.3 arcseconds/pixel). ULTRACAM
mounts at the Cassegrain focus of the WHT
S-CAM
S-Cam is a prototype Superconducting Tunnel Junction (STJ) camera
developed by the Astrophysics Division at ESTEC. The instrument is based on a
6x6 array of 25 micron tantalum junctions operating at
a temperature of 0.32 K and covering the 350-650 nanometer range.
The camera is designed to operate at the Nasmyth focus of the WHT.
CIRSI
CIRSI is a panoramic wide-field near-infrared imaging camera which
uses four Rockwell HgCdTe 1024x1024 detectors. The survey instrument is
scientifically versatile and as easy to use as a large format CCD
camera which has been used on both the INT and WHT at wavelengths
up to H band.
LDSS2
The Low Dispersion Survey Spectrograph (LDSS-2), mounted at the Cassegrain focus of
the WHT, is a multi-slit spectrograph designed to obtain spectra of
objects lying in the apparent magnitude range 20 to
23. The LDSS system is a focal
reducer providing a collimated space where grisms
of different dispersion may be placed. A focal plane
mask is used to isolate the objects to be studied
together with regions of night sky. Previously a Common User
instrument at the ING, LDSS2 has recently been adopted by Durham.
TAURUS
TAURUS is a wide-field (9 arc min) imaging Fabry-Perot interferometer,
with a resolving power between 2,000 and 100,000,
which can also be used as a focal reducer for imaging observations.
Formerly a Common User instrument at the WHT, TAURUS is now owned
by the IoA, Cambridge.
Future Instruments |
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Last Updated: 23 September 2004 |
