Configurations
CANARY Design
The CANARY experiment has been in operation since 2010 and uses several telescopes at the observatory to perform a range of measurements. The current CANARY configuration offered for OPTICON-funded observations comprises the following:
- Closed-loop tomographic NGS mode, with 3 off-axis NGS SH-WFS that can be positioned within a 2 arcminute derotated field
- An on-axis NGS SH-WFS for calibration and SCAO operation
- A 20W sodium LGS launched from an auxiliary telescope positioned approximately 40m from the WHT optical axis
- An on-axis LGS SH-WFS on a removable kinematic bench
- A low-order 52-actuator closed-loop DM and tip/tilt mirror
- Approximately 1 x 1.5m of free bench space for visitor instruments fed with a 1 arcminute diameter f/11 AO corrected beam.
- A reconfigurable real-time control system running on standard CPU machines, written in C.
- A comprehensive telescope simulator containing NGS and LGS sources, as well as 2 turbulent phase screens and a range of pupil alignment and calibration masks
- A sodium profiling (6' field 589nm imager) instrument installed in the 2.5m INT
CANARY is not currently configured with its 4 Rayleigh LGS system, NIR camera, 241-actuator open-loop deformable mirror or Stereo-SCIDAR instrument. If you wish to use any of these, please contact the CANARY team to see if it's feasible to do so.
Visitor experiments
We expect that the majority of propsals will require only the use of existing CANARY infrastructure, the installation of an experimental component at the AO-corrected focus, or modifications to the real-time control system for testing e.g. new controllers or interfacing new cameras. You are welcome to request the use of any or all parts of the CANARY system, ranging from the full tomographic AO system with sodium LGS, to SCAO on bright objects, or observations that require the INT only.
The CANARY team will assist with operations and any modifications, but their effort is limited so proposals that require significant amounts of effort from the CANARY team will be difficult to support. We advise you to discuss your proposals with them before submitting to see if what you propose is feasible within the time constraints.
What CANARY cannot do
CANARY provides a unique facility to undertake a huge range of potential experiments, however it was designed as a tomographic AO demonstrator, not a common user instrument and therefore has some limitiations:
- CANARY was not designed for high throughput and is limited to guide stars brighter than R=11.
- CANARY is a low-order AO system with 0.6m diameter subapertures. This, coupled with some residual high-frequency aberrations present on the DM, is sufficient to get a H-band Strehl ratio of 0.3 in SCAO mode in typical operating conditions.
- When operating in multi-NGS mode, there are ~50 targets that can be observed. Don't expect sky coverage if operating in this mode.
Detailed design
Further details on the CANARY design can be found below:
- CANARY optical design file (.zmx)
- INT imaging camera optical design file (.zmx)
- Sodium LGS WFS design document
- Elongated LGS experiment interface diagram
- Space envelope description (precise details on available space envelope to follow)
There are also several thousand pages of design documentation covering the various stages of CANARY development from 2009 onwards, so if you require any more information on any aspect of CANARY please contact the CANARY team.
