Key R&D Activities for the LSST Camera DOE HEP Program Review June 13, 2007 Kirk Gilmore (SLAC) LSST Camera Manager

2 Brandeis J. Bensiger, K. Hashemi, H. Wellenstein Brookhaven National Lab S. Aronson, C. Buttehorn, J. Frank, J. Haggerty, P. Kuczewski, M. May, P. O’Connor, V. Radeka, P. Takacs Florida State H. Wahl Harvard University N. Felt, J. Geary (CfA), J. Oliver, C. Stubbs Lawrence Livermore National Lab S. Asztalos, K. Baker, L. Hale, S. Olivier, D. Phillion, L. Seppala, W. Wistler Oak Ridge National Laboratory P. Stankus, G. Young, V. Cianciolo, C. Britton (joint faculty UT) N. Ericson (joint faculty UT) Ohio State University K. Honscheid, R. Hughes, B. Winer Purdue I. Shipsey, J. Peterson 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), P. Kim, T. Lavine, S. Marshall, M. Nordby, M. Perl, L. Price, A. Rasmussen, D. Rich, 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 University of Washington L. Rosenberg University of Tennessee B. Blalock, R. Chun Wayne State D. Cinabro LSST Camera Team Members

DoE HEP Program Review June 13, Camera R&D Overview Detector requirements: () Detector requirements: (Radeka/Geary - BNL/SAO) – 10  m pixel size Pixel full-well > 90,000 e – High QE 400 – 1000 nm – Low noise (< 5 e – rms), fast (< 2 sec) readout, stable T (-90 C) Package large number of detectors, with integrated readout electronics, Package large number of detectors, with integrated readout electronics, with high fill factor and serviceable design with high fill factor and serviceable design (O’Connor/Oliver - BNL/Harvard) Sensor and focal plane precision alignment/stabilility/motion control Sensor flatness 5u p-v, focal plane flatness 10u p-v () Sensor and focal plane precision alignment/stabilility/motion control Sensor flatness 5u p-v, focal plane flatness 10u p-v (Takacs/Rasmussen/Schindler - BNL/SLAC/SLAC) Cryostat contamination control - (Schindler - SLAC) Cryostat contamination control - (Schindler - SLAC) Fabricate large diameter (75cm) filters with uniform coatings () Fabricate large diameter (75cm) filters with uniform coatings (Olivier - LLNL) Data Acquisition/ Camera Control Protocol - ( ) Data Acquisition/ Camera Control Protocol - ( Schalk - UCSC) Constrained volume (camera in beam) () Constrained volume (camera in beam) (Nordby - SLAC) –Makes shutter, filter exchange mechanisms challenging

4 Camera: International R&D Contributions Filter mechanism: M. Nordby (SLAC) The LPNHE team is taking responsibility of studying and prototyping... P. Antilogus (LPNHE) will act as contact scientist and G. Daubard (LPNHE) as technical contact. Shutter Development: M. Nordby (SLAC) Bonn Group is studying Gordon Bowden (SLAC) design. Dialog between Bonn and SLAC started. Klaus Reif of the University of Bonn is main contact and head of shutter group Filter development: K. Gilmore (SLAC) LSST is currently looking for qualified vendors to evaluate filters. R. Pain (LPNHE) and the LPNHE/Lyon teams will help coordinate SAGEM evaluation Analog signal processing ASIC: J. Oliver (Harvard) A joint LAL+LPNHE team will take responsibility of prototyping the FE ASIC. P. Antilogus (LPNHE) will act as contact scientist and V. Tocut (LAL) as technical contact. Software slow control: T. Schalk (SLAC/UCSC) The IN2P3 groups will evaluate a possible contribution in the control software and hardware of the camera. P. Antilogus (LPNHE) will act as contact for this effort. Instrumental calibration: D. Burke (SLAC): The LPNHE group will participate in the definition of an instrumental calibration strategy for LSST. P. Astier (LPNHE) will act as contact scientist for this effort.

DoE HEP Program Review June 13, Sensor Fabrication and Delivery Schedule _______________________________________________ Contracts with four vendors for study phase Goals: – technology development leading to back-illuminated sensors with thick, fully depleted substrate and transparent conductive window – large-format, small pixels Schedule – flat, 4-side-buttable package 1. Study - Jan06-Feb07 2. Prototype - Jul07-Aug09 3. Production - Oct09-Sep12 Risks 1. CCD performance 2. Mulit-port R.O. 3. Flatness 4. Packaging

DoE HEP Program Review June 13, Shutter Reliability _______________________________________________ - Required cycle life is long - Belt-drive system could behave differently depending on orientation - Blade dynamics could be an issue at high-speed - Wear and near-constant motion could produce particulates that would contaminate L3 lens and filters Shutter Assembly Closed Motors with 3 drive pulleys of different diameters Shutter Assembly Open Drive rail contains ball-roller track with 6 carriages for each of the blades Blades are contoured to fit around convex crown of L3 to save Z-space Blades stack beyond field of view when not in use Guide rail channel tracks cam followers in blades to reduce sagging of blades

DoE HEP Program Review June 13, Filter Fabrication _______________________________________________ R&D: Coating of large filters requires large coating facilities with precision process controls to meet LSST filter coating specs.

DoE HEP Program Review June 13, Electronics Packaging in a Constrained Volume _______________________________________________ The Raft-Tower is comprised of sensors, structures requiring precise alignment, and high-density front-end electronics boards. Raft Tower Raft Tower Front-side View FEE Boards Raft Flex cables and Thermal Straps Front-end ASIC

DoE HEP Program Review June 13, DAQ/CCS Communications Protocol R&D Determine functionality of controls and data acquisition Prototype test stand to establish communication configuration Prototype system to facilitate sensor and raft development OCS SAS SDS FCS DM MCM DAQ Client interface Subsystem modules Control interface CCS Controls Architecture

DoE HEP Program Review June 13, Filter Exchange Mechanism R&D Prototype Questions Five filters just fit in the camera Double-rail mechanism could bind in operation Clamps and locking pins could fail Filter Changer and Carousel Assemblies Rails and ball screw provide linear actuation Yoke Linkage converts linear actuation to follow filter path Double-rail provides X, Z, and tilt motion of filter Filter clamp into base cradles Carousel ring bearing mounts to back flange