Development of IRMS OIWFS requirements - requires TMT AO support for PSF / sensitivity models
The largest uncertainty in the entire study seems to be whether the patrol range for a OIWFS exterior to the vacuum vessel provides sufficient sky coverage without blocking the spectrographic field (because it would be rather far from the focus).
Notes from the last meeting minutes:
We discussed the basic architectural options for the OIWFS
Strategy is to evaluate the performance vs. sky coverage for a 'one-side', no-incursion, external-to-the-dewar patrolling sensor (similar to IRIS OIWFS), and then address any performance shortfall if necessary
Possible avenues for larger sky coverage if needed:
Allow some incursion into spectroscopic FoV (probably diminishing gains because an external patroller is so far from focal plane)
'Two-sided' dual OIWFS to patrol each side without incursion
Focus sensing strategy may impact performance as well (e.g. 2x2 SH WFS v. pyramid v. separate (slower) focus sensor(s))
Refinement of IRMS cost estimate using best estimate of MOSFIRE as-built costs
Actions
Rich
Contact Brent at TMT to initiate discussion of OIWFS performance model
Contact Sean and Ian to consolidate non-CIT MOSFIRE costs
Update IRMS mini-study schedule to reflect MOSFIRE and other delays * Discuss timing of interim review with Luc (targeting May 2012 now)
Bob
Consolidate CIT MOSFIRE cost summary, including sort of trail of shop charges
All
Finish MOSFIRE!
Meeting schedule
The next IRMS team meeting will be announced pending MOSFIRE and other progress.