First light: June
1992.
De-commissioned:
Designed and built by:
Department of Physics, National University of Ireland, Galway.
Description: This photometer
goes on several telescopes around the world, including WHT (Cassegrain and
Nasmyth - GHRIL - focus). An array of dichroics splits up the incident beam in broad band
regions, each region projected onto the detector. The photon-counting tube
detects each photon arrival by knocking of an electron (photo cathode)
which is accelerated through an electric field until it hits a micro channel
plate which produces a shower of electrons. This shower is detected on
a fine grid of wires and, using a techique called coincidence logic, the
photons xy position is recorded together with the arrival time. The two-dimensional
image builds up on the 'MAMA' display. Furthermore, 3 fibres acts like
single channel photometers (ADC). Detector size is ~ 1000 x 200 'resolution
elements'. Each element is 24 microns corresponding to 0.1" on sky. Field
of view is ~ 100" x 20"
Some scientific highlights:
More information: M
Redfern et al., 1992, "First Scientific Results from TRIFFID", Gemini
Newsletter, 38, 1.
More photos of this instrument: http://www.ing.iac.es/PR/archive/wht/instruments.html
