The Large Synoptic Survey Telescope: Design and Performance SPIE Marseille, France June 24th, 2008 Kirk Gilmore LSST Camera Manager Stanford/SLAC/KIPAC

________________________________________________ Science Objectives Drive System Requirements Image Quality Image Quality f/1.25 beam f/1.25 beam Large focal Plane Large focal Plane Dark Energy / Matter Dark Energy / Matter –Weak lensing - PSF –Shape/ Depth / Area –Super Novae + Photo z –Filters (ugrizy)

3 Four Main Science Themes for LSST: 1. Constraining Dark Energy and Dark Matter 2. Taking an Inventory of the Solar System 3. Exploring the Transient Optical Sky 4. Mapping the Milky Way Major Implications to the Camera: 1.Large Etendue 2.Excellent Image Quality and Control of PSF Systematics 3.High Quantum Efficiency over the Range 320 – 1,050 nm 4.Fast Readout

LSST Concept 8.4 Meter Primary Aperture –3.4 M Secondary –5.0 M Tertiary 3.5 degree Field Of View 3 Gigapixel Camera –4k x 4k CCD Baseline –65 cm Diameter –Six Filters 30 Second Cadence –Highly Dynamic Structure –Highly Parallel Readout Accumulated depth ~27 mag. in each filter over 10y Data Storage and Pipelines ~ 18Tb/night! Design Telescope and Camera as a Single Instrument

________________________________________________ LSST Optical Design f/1.23 <0.20 arcsec FWHM images in six bands:  m 3.5 ° FOV  Etendue = 319 m 2 deg 2 LSST optical layout Polychromatic diffraction energy collection Detector position ( mm ) Image diameter ( arc-sec ) U 80%G 80%R 80%I 80%Z 80%Y 80% U 50%G 50%R 50%I 50%Z 50%Y 50%

________________________________________________ LSST Camera Optical Design

________________________________________________ LSST Deliverable Org Chart Electronics Oliver (Harvard) WBS Sensor/Raft Development Radeka/O’Connor (BNL) WBS Optics Olivier (LLNL) WBS Cryostat Assembly Schindler (SLAC) WBS Calibration Burke (SLAC) WBS Camera Body Mechanisms Nordby (SLAC) WBS Data Acq. & Control Schalk (UCSC) WBS Corner Raft WFS/Guider Olivier (LLNL) WBS Utilities Nordby (SLAC) WBS Sensors/Filters Pain/Antilogus (IN2P3) LPNHE, LAL, APC, LPSC, LMA

________________________________________________ LSST Camera Team Brandeis University J. Besinger, K. Hashemi Brookhaven National Lab S. Aronson, C. Buttehorn, J. Frank, J. Haggerty, I. Kotov, P. Kuczewski, M. May, P. O’Connor, S. Plate, V. Radeka, P. Takacs Florida State University Horst Wahl Harvard University N. Felt, J. Geary (CfA), J. Oliver, C. Stubbs IN2P3 - France Detailed in IN2P3 section of this report Lawrence Livermore National Lab S. Asztalos, K. Baker, S. Olivier, D. Phillion, L. Seppala, W. Wistler Oak Ridge National Laboratory C. Britton, Paul Stankus Ohio State University K. Honscheid, R. Hughes, B. Winer Purdue University K. Ardnt, Gino Bolla, J, Peterson, Ian Shipsey Rochester Institute of Technology D. Figer Stanford Linear Accelerator Center G. Bowden, P. Burchat (Stanford), D. Burke, M. Foss, K. Gilmore, G. Guiffre, M. Huffer, S. Kahn (Stanford), E. Lee, S. Marshall, M. Nordby, M. Perl, A. Rasmussen, R. Schindler, L. Simms (Stanford), T. Weber University of California, Berkeley J.G. Jernigan University of California, Davis P. Gee, A. Tyson University of California, Irvine D. Kirkby University of California, Santa Cruz T. Schalk University of Illinois, Urbana-Champaign J. Thaler University of Pennsylvania M. Newcomer, R. Van Berg Wayne State University David Cinabro

________________________________________________ Camera Layout Cryostat L1/L2 Assembly Filter Changer Filter Shutter

________________________________________________ CCD PACKAGED CCD RAFT From sensors to rafts to raft/towers The heart of the system TOWER 3 x 3 submosaic of CCDs front end electronics thermal management components Tower is an autonomous, fully-testable 144 Mpixel camera carrier CCD connector alignment pins baseplate thermal straps FEE boards housing (cold mass) 3-pt. mount cooling planes

________________________________________________ LSST focal plane sensors

________________________________________________ BNL and sensor group are providing leadship For sensor development -50V -10V X-ray images Request for proposals for prototype science CCDs – issued Feb – contract award June high-resistivity, thick CCDs from study program have been extensively characterized – design models validated – behavior of dark current, quantum efficiency, and point spread function vs. thickness, temperature, and electric field – flatness and surface morphology – antireflection coating CCD controllers for 4 new test labs under construction – UC Davis, SLAC, Paris, Purdue – allows full-speed testing of segmented sensors Components for CCD/electronics chain testing in assembly (Raft/Tower electronics)

________________________________________________ 32-port CCD 3x port CCDs Raft tower electronics partitioning/temp zones Front End Boards (6 per raft): 144-channels of video signal chain through CDS processing clock and bias drive ASIC-based (ASPIC/SCC) BEE motherboard and backplane: differential receiver signal chain ADC (16+ bits) buffers data transport to optical fiber clock pattern generation clock and bias DACs temperature monitor / control ~175K ~235K Flex cables (~ 500 signals) Cryo Plate (~170k) Cold Plate (~230k) ~185K Molecular Flow Barrier

________________________________________________ RFP for Prototyping Filters in cm dia. Curved surface Filter is concentric about the chief ray so that all portions of the filter see the same angle of incidence range, 14.2º to 23.6º Filter is concentric about the chief ray so that all portions of the filter see the same angle of incidence range, 14.2º to 23.6º Specs Filter RFP being sent out to selected vendors Filter prototyping will qualify vendors to fabricate science filters Half-Maximum Transmission Wavelength

________________________________________________ Contamination test chamber at SLAC Fore or Preparation Chamber Main Chamber FORE MAIN ANTE cold finger Sample Preparation Chamber Outgassing Analysis Chamber Optical Transmission Chamber Sample Entry Straight- Thru Valve Optical Entry

________________________________________________ IN2P3 - France R&D CNRS - National Center for Scientific Research IN2P3 - National Institute for Nuclear Physics and Particle Physics APC - Lab for Astroparticles and Cosmology (Paris) CC-IN2P3 - Computing Center of IN2P3 (Lyon) LAL - Lab of Linear Accelerator (Orsay) LMA - Lab of Advanced Materials (Lyon) LPSC - Lab for Subatomic Physics and Cosmology (Grenoble) LPNHE - Lab for Nuclear Physics and High Energy (Paris)

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Fin

FY-09FY-10FY-11FY-12FY-13 FY-14 FY-15FY-16 The new LSST timeline generated with agency guidance following the successful CoDR in Sep., ‘07 FY-17 FY-07FY-08 NSF D&D Funding MREFC Proposal Submission NSF CoDR MREFC Readiness NSF PDR NSB NSF CDR NSF MREFC Funding Commissioning Operations DOE R&D Funding DOE CD-0 DOE MIE Funding DOE CD-1 DOE CD-2 DOE CD-3 Sensor Procurement Starts DOE CD-4 Camera Delivered to Chile Camera Fabrication (5 years) Telescope First Light DOE I&C Funding Camera Ready to Install NSF + Privately Supported Construction (8.5 years) System First Light ORR Privately Supported R&D and Construction (7 years)

________________________________________________ Camera Construction Costs Request to DOE $87M

________________________________________________ Camera risk mitigation plan prior to construction R&D EffortPlan Status Demonstrate sensor performance Establish all specs are met: Flatness, high fill factor, electrical parameters, Study phase sensors received and being evaluated Efficient sensor procurement Establish cost, yield and performance of sensors PO’s being drafted that address risk areas. Prototype phase starting Establish reliability of shutter mechanism Build prototype shutter and test Design completed. Procurement of parts begun Evaluate outgassing properties of cryostat components Contamination control demonstrated in engineering cryostat Contamination testing started. Materials selection process begun. 75cm filter w/multilayer coatings produced with non- uniformity of <1%. Fabrication of samples in large coating chamber to evaluate uniformity of filter transmission Passbands defined. Total system throughput modeled. Some witness samples already produced. RFP to potential vendors ready.