TMT AO & Possible Contribution of Japan Hideki Takami (Subaru Telescope)
Subsystems Mounted on Telescope (TMT document) Red: Possible Japanese collaboration M2 assembly: Laser launch telescope (LLT) conventional (CM2) or adaptive (AM2) Laser BTO Mirrors or Optical fiber Laser rooms 3x 50W laser Instruments, AO systems, APS
TMT-Mapping AO Modes to Instrumentation Capabilities (TMT document) 10-15’ GLAO WFOS First Light 5’ MOAO (SRD) IRMOS $30.6M MCAO FoV 0.5-2.0’ $31.8M IRIS 5-10” LTAO HROS ExAO (SRD) 2” MIRES PFI High Diffraction- Enhanced Seeing- Contrast Limited Seeing Limited 0.01-0.02” Image Quality
First Light AO Architecture for TMT Supports Narrow-Field Instruments Using Existing/Near-Term Components/Concepts (TMT document) 2011 FDR • 3-6 sodium laser guidestars Laser Guide 2016 Commission • 3 50W, CW lasers Star Facility Conventional Secondary • 3 LGS WFS • 6 LGS WFS MCAO LTAO • Current piezo • 2 high-order (NFIRAOS) DM technology piezo DMs Narrow-field Mid IR IRIS Near IR Instruments Instruments
An Adaptive Secondary Mirror Enables GLAO for Wider-Field Instruments and Improves Performance for Mid IR Instruments (TMT document) Laser Guide Star Facility • Compensation at moderate Adaptive spatial and temporal frequencies for low-order correction or Secondary woofer-tweeter control • 4 LGS WFS MCAO GLAO (NFIRAOS) • Reduced Wider-field • Enhanced Mid IR Narrow-field background and seeing Vis/Near IR Instruments Near IR enhanced Instruments throughput Instruments
MEMs Deformable Mirrors Enable MOAO for Enhanced Imaging and Spectroscopy of Multiple Small Objects within a Larger Field (TMT document) MEMS-DM • 8 sodium laser guidestars Laser Guide • 3 50W, CW lasers Star Facility Adaptive Secondary • 8 LGS MCAO MOAO GLAO WFS (NFIRAOS) • MEMS Wider-field Mid IR Narrow-field Multi-Object IFU Vis/Near IR Instruments Near IR Spectrometer Instruments Instruments
First light AO: IRIS will be mounted on the top port of NFIRAOS (TMT document) NFIRAOS is a dual conjugate AO system => Wide Field (~2’) NFIRAOS IRIS Order 61x61 DM and TTS at h=0 km Order 75x75 DM at h=12 km – Better Strehl and larger field than current AO systems Other NIRES
Schematic of INSTRUMENT Activity (TMT document) 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 WFOS FDR TES CO T MM IRIS PDR FDR NFI CO RAO MM S INST 3 CoD PDR FDR CO R MM INST 4 CoD FDR CO R MM INST 5 CoD PDR FDR CO R MM INST 6 CoD PDR FDR R INST 7 CoD PDR FDR R INST 8 CoD PDR FDR R
Possible collaboration items with TMT about AO Red: Possible Japanese collaboration M2 assembly: Laser launch telescope (LLT) conventional (CM2) or adaptive (AM2) Laser BTO Mirrors or Optical fiber Laser rooms 3x 50W laser Instruments, AO systems, APS
Adaptive 2ry Requirements of AM2 for TMT - 1800 actuator, 400 modes, - 3.1 m diameter, convex mirror - 4-5 mm thickness glass (7 cm spacing) - 20 Hz BW (AO closed loop BW -3dB), - good for MIR AO or woofer, +/- 150 um (end to end, for windshake and chopping) AM2 is not fit in construction budget, upgrade 4-5 year after the first light. ~2020 => Japanese industry is expected as the manufacturer
First light AO collaboration in discussion with TMT 1. Laser & Fiber - TMT now has a candidate vendor of Laser. As for Japan’s contribution, 10 W CW laser is OK, however required 25 W is new area for us. => Considering the TMT first light is 2016, It is worth to discuss with them. - Fiber: Mitsubishi-cable (We will collaborate) Our 35m fiber is almost meet the requirement of TMT 2. RTC for NFIRAOS (continue discussion) GRAPE would be a candidate. TMT has a pre-conceptual design to use 3 DSP and 7 FPGA. Those chips have limitation in memory size. Requirement to the performance of Core part - Input/output 120k pixel in 0.5 msec/WFS x 6WFSs - gradient computation etc 35k grad for 6WFSs (it is smaller than others) - 175M multiply & accumulation /frame in ~1ms => FFT & spars matrix op. - 7400 actuators drive, 2DMs 61x61, 73x73 2008-2009 conceptual design study. 2013 mid delivery of RTC
Summary 1. TMT covers wide range of AO in their plan 2. TMT will build only one LGSAO system for their First light. 3. Japan has possible collaboration technologies to contribute their FL AO (The contribution would be subsystem or component level, good for starting?) 4. Other several Instruments/AO require additional budget which will be commissioned in 2018- 2022 (We have a chance to make significant contributions and should have ideas what we want to do)
Recommend
More recommend
