W. M. Keck Observatory’s Next Generation Adaptive Optics Preliminary Design & Path Forward Peter Wizinowich, Sean Adkins, Rich Dekany, Don Gavel, Claire Max for NGAO Team: R. Bartos, J. Chin, A. Conrad, A. Delacroix, R. Kupke, C. Lockwood, J. Lyke, E. McGrath, D. Medeiros, D. Morrison, C. Neyman, S. Panteleev, M. Pollard, M. Reinig, T. Stalcup, S. Thomas, M. Troy, K. Tsubota, V. Velur, K. Wallace, E. Wetherell SSC, Waimea July 7, 2010
2 Flowed-Down Key Architectural Features
3 NGAO System Architecture Key Features: 1.Fixed narrow field laser tomography 2.AO corrected NIR TT sensors 3.Cooled AO enclosure 4.Cascaded relay 5.Combined imager/IFU instrument
44 NGAO on Nasmyth Platform
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6 DAVINCI – Imager & IFS Entrance window Coronagrap h mask wheel Imager detector head Imager/IFS selector mirror Pupil imager wheel Filter and pupil mask wheels IFS detector head Grating selector wheel On axis imager 28.7" x 28.7" FOV –7 mas pixel scale On axis selectable IFS –50 mas spatial scale FOV 5.6" x 3" –35 mas, FOV 3.92" x 2.1" –10 mas, FOV 1.12" x 0.6"
7 AO Enclosure Model DAVINCI Instrument Overhead HEPAs LGSWFS Gowning Room Area AO Bench Secondary Instrument Interferometer DSM Thermal Management DM Electronics
LGS Facility TOPTICA/MPBC RC Optical
9 Science Case Performance Summary Galaxy assembly: 30º zenith angle, 60º galactic latitude, 30 min integ.
AO correction of IR tip-tilt stars has big benefit for sky coverage Galaxy assembly science case Current Keck TT Current Keck EE NGAO TT NGAO EE
11 NGAO is robust against conditions and design assumptions
12 NGAO changes the Keck AO observing experience Monte Carlo performance estimate simulating 44 nights observing (Galaxy Assembly science case), drawing random values for r 0, wind speed, sodium abundance, and zenith angle Includes comparison with M. Liu’s measured K2 LGS data ( = 17%), the model prediction for K2 LGS ( = 20%), and NGAO predict ( = 70%)
Path to Early Science Benefits from NGAO is Already Under Way - 1 NGAO laser launch telescope –NSF-MRI (Aug/09) funding to procure & implement a K2 center launch telescope NGAO laser –Preliminary designs completed (Dec/09) from 2 vendors. Collaboration with ESO, AURA, GMT & TMT. TOPTICA/MPBC selected to begin final design. –MRI proposal submitted to procure & implement 1 st NGAO laser on K2. Collaboration with TMT & ESO. 13
Path to Early Science Benefits from NGAO is Already Under Way - 2 PSF reconstruction –Collaboration with Gemini & U. Groningen to demonstrate on-axis NGS AO PSF reconstruction on Gemini & Keck –Plan to implement off-axis LGS AO PSF reconstruction with Keck –MASS/DIMM implemented (Sept/09) as a Mauna Kea facility Focal anisoplanatism reduction –Risk reduction to demonstrate 20% reduction using Cn2 data Tip-tilt vibration reduction –Risk reduction plan to prototype parametric oscillator on K2 AO NIR tip-tilt sensing (no object selection or AO correction) –ATI (Jun/10) funding to implement a near-IR tip-tilt sensor 14
15 Major Keck AO Science Capability Milestones Future
16 Cost Estimate by FY (then-year $k) Assumes 3.5% annual inflation $1.5M (3.8%) of $60M cap reserved for schedule contingency $58.5M (then-year) $53.9M (FY10)
17 Cost Estimate versus Funding Need a path to $49.3M (then-year $) or $44.5M (FY10 $) Includes ~$11M (then-year) for detailed design with contingency
Path Forward
19 Funding Options (Project Perspective) 1.Proceed with full NGAO plan (as outlined at PDR & endorsed by Review Committee) or 2.Proceed with staged implementation on the path to the full NGAO system, with clear near-term science return We will discuss each of these in turn
20 1.Proceed with Full NGAO Plan Potential path to significant funding (dependent on Astro2010 report) : –Submit an unsolicited proposal to MPS’s existing “Mid- Scale Instrumentation Program” to fund detailed design This program has funded multiple AST programs (Atacama Cosmology Telescope, Murchison Wide-Field Array, LSST design, GSMT development, etc.) –Develop a proposal to NSF for full funding –Continue private fundraising efforts This is the path recommended by the NGAO team –We would continue to seek early science / staged opportunities
NGAO has demonstrated that it can successfully compete & collaborate 21 Demonstrated fund raising & leveraging successes: One (extreme) interpretation: 36 nights $9.0M or $249k/night
2. Staged Implementation Path to NGAO Significant “development chunks” that are on the path to the full NGAO system, with clear near-term science return Criteria for selection: each development stage should accomplish the following goals, with equal weight: –It should provide early science return to the WMKO community –It should be on the path to the full NGAO project In addition a proposal should accomplish the following: –It should help keep the NGAO team working together on NGAO goals –It should reduce NGAO risk –It should allow us to leverage the work of others, especially TMT Potential funding sources: NSF ATI, MRI, TSIP & private fundraising past the January 2011 deadline 22
Preliminary list of possible early “stages” 1.New laser (if not funded by MRI) 2.Develop PSF reconstruction techniques –Will be useful to all Keck AO users –Key to precision photometry and astrometry with NGAO 3.Increase sky coverage of existing AO system by building an AO feed to the new infrared tip-tilt sensor –Would serve as prototype for NGAO’s tip-tilt arms 4.Implement laser tomography on existing AO system –Increase Strehl & enclosed energy by reducing “cone effect” –Risk/cost reduction collaboration opportunities on RTC & WFS camera In support of decision making NGAO team & NSAT will evaluate science return, feasibility & cost of “stages” 23
In Closing Keck AO has been very successful scientifically NGAO preliminary design received a very strong endorsement NGAO can successfully compete for & leverage Federal funding NGAO Team ready to compete for funding & to deliver this key element which is “critical to WMKO’s future as a facility producing forefront science” (NGAO Review Panel) Keck AO NGAO