The Simons Observatory CMB S4 Meeting 2/28/17

Transcription

1 The Simons Observatory CMB S4 Meeting 2/28/17 Mark Devlin Presenting the work of the Science and Technical Working Groups with special thanks to the leads. Please engage them directly for more complete discussions. Science Working Groups Technical Working Groups Time Domain Matthew Hasselfield and Yuji Chinone Measuring-r - Josquin Errard and David Alonso High-ell - Erminia Calabrese and Dan Green Lensing - Blake Sherwin and Neelima Sehgal Clusters Nick Battaglia and Simone Ferraro Sources Megan Gralla and Andrew Baker Detectors Hannes Hubmayr, Suzanne Staggs and Aritoki Suzuki Readout Matt Dobbs and Zeesh Ahmed Electronics and DAQ Laura Newburgh Optical Design Mike Niemack and Phil Mauskopf Platforms (Telescope) Mark Devlin, Simon Dicker, and Adrian Lee Cold Optics Jeff McMahon and Enzo Pascale Cryogenics Nick Galitizki, Marius Lungu, Bob Thornton Calibration/Systematics Rolando Dunner, Brian Keating and Sara Simon Site and Logistics Kam Arnold and Lucio Piccirillo 1

2 The Simons Observatory Goals are Driven by the Science Working Groups and Informed by CMB S4 Time domain: modeling Chilean atmospheric noise, assessing HWP data from ACT/PB. Measuring-r: forecasts using simulated Galactic maps, studying optimal band configuration and sizes of small cameras. High-ell: multi-frequency spectrum forecasts for Neff including atmospheric noise and small-scale foregrounds. Lensing: forecasts for mnu and delensing, assessment of bands needed. Clusters: forecasts for m ν /w and astrophysics from tsz/ksz, size of large telescopes and number of bands. Sources: assessing case for source science. Realistic Noise Projections Final SO Measurement Requirements expected spring 2017 Current assessments: Small Aperture Camera: ~0.3 resolution at 150 GHz which implies ~0.5 meter aperture 7+ bands in ~0.5m cameras Larger for low frequency bands Large Aperture Telescope 1.8 resolution at 150 GHz which implies ~5+ meter aperture 3-5 bands Sky Coverage Multiple small areas for r null tests each patch 2-3% of the sky Larger area for N eff /m ν /astrophysics overlapping LSST, with < 5 µk/arin noise 3 and 5 uk/amin noise See Science Break Out Sessions

3 Large Telescope Three Mirror Anastigmat 5 m Cross Dragone Gregorian 10 m Design Considerations: FWHM 1.8 (subject to change) Focal plane Image Quality Focal Plane Area Net telescope sensitivity Cost/buildability Camera placement/access Co-moving ground shield/baffles ACT PB/SA CLASS What measurement has few eyes in the morning, many at noon and one in the evening? Site design is underway in consultation with CONICYT and site neighbors. See Optics Break Out Session

4 Requirements for 250,000 detectors 47,600 detectors/telescope 5-6 telescopes 2.3 m receivers m 83,800 detectors/telescope 3-4 telescopes 3-4 receivers CMB S4 Receiver Configurations for a 5-meter Crossed Dragone f/3 Telescope 85,000 detectors 83,800 detectors 2.3 m m CMB S4: 2.5 meter diameter cryostats. 1.8 m 1.8 m diameter cryostat Simons Observatory Receiver Configurations Simons Observatory: 1.8 meter diameter cryostat. Partially filled with up to 35K detectors. 7 wafers per large optics tube Each wafer is 1,700 detectors (averaged over different frequencies) See Detector and Cold Optics Break Out Sessions

5 Data & software plan Ideal pipeline Identify computation requirements On-site storage, processing, transport CPU and disk space requirements for pipeline: data storage, processing (cuts, calibration, maps, power spectra), and simulations Use previous experience to: define software interfaces between analysis sets, including data file format identify where inefficiencies will cause problems for larger data sets Bring ourselves into the modern era: git based repositories for all code code review by peers standardized debugging and code testing Improved documentation Full time data manager position. Identify opportunities for infrastructure investment in data and software Simons Observatory: 35,000 Detectors 2TB/day CMB S4: 500,000 Detectors 140 TB/day This will get harder to do with more data! Our current infrastructure does not come close to addressing this challenge.

6 1/17 1/18 Large Telescope (Small Aperture Base + 1 year) Optics Review RFP AWARD PDR CDR Mfg Start 1/19 Manufacture 18 mo. 1/20 Acceptance Test Final Assembly Ship/install Installation Done 1/21 Final Test Start Observations Simons Observatory Schedule/Timeline and Planning Large Telescope Receiver (Small Aperture Camera + 1 year) Manufacture 11 mo. Unpack/ Integration/Test Test 8 months Concept Freeze RFP AWARD PDR CDR MFG Cryo Ship Acceptance Acceptance Installation Done OR Detectors & Readout PDRs PDRs CDRs Production 1 yr Development prioritization Site Preparation Integration and test 1 st Det & MUX Integration All wafers Rec 1 Ship Rec 1 Telescope pads & Utilities Done 4/20 All wafers Rec 2 Ship Rec 2 OR.. This schedule requires early decisions: Optics Design Configuration of the large telescope Interface with the receiver(s) Shielding/baffle strategy Receiver concept The SO should be returning science on the 4-5 year time scale. The large aperture telescope design should be consistent with CMB S4 goals. The final configuration will depend on updated cost models and continued CMB S4 planning. The schedule allows us to consider configuration changes through spring 2018.