Predicted Sky Coverage of NFIRAOS on TMT

David Andersen, Lianqi Wang, Brent Ellerbroek & Glen Herriot
TMT has chosen the MCAO system NFIRAOS to be its first light AO system in part to provide astronomers with exceptional sky coverage. The TMT science requirements demand that its AO system provide wavefront errors of less than or equal to 191 nm at the galactic pole at least 50% of the time (under median atmospheric conditions when observing at zenith). This requirement drove many aspects of the NFIRAOS design from the size of the...