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New Project Possibilities. Tom Shea October 5, 2006. Motivation. SNS was a uniquely organized project – multilab partnership, “interesting experience” Example: Evolution of SNS Diagnostic Systems Began with 3 labs, each with their own concepts for virtually identical systems
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New Project Possibilities Tom Shea October 5, 2006
Motivation • SNS was a uniquely organized project – multilab partnership, “interesting experience” • Example: Evolution of SNS Diagnostic Systems • Began with 3 labs, each with their own concepts for virtually identical systems • Almost had 3 linac BPMs, 3 linac BCMs, … • Early collaboration meetings helped identify commonality, reduce cost by about 3 M$, produce systems that were useful during first beam • More generally, communication performance is correlated with technical performance*. * Allen, Goldhar, Baker, from 1964 and on. Controls Brown Bag, October 5, 2006
Organization Control flow Controls Brown Bag, October 5, 2006
Organization Knowledge silos Controls Brown Bag, October 5, 2006
Probability of Communication T. Allen, Sloan WP 165-97, MIT, 1997 Controls Brown Bag, October 5, 2006
Effect of Department Membership compared to Project Membership T. Allen, Sloan WP 165-97, 1997 Controls Brown Bag, October 5, 2006
Target System Gamma Monitors • ASD’s BLM ion chambers • Monitor target water and Mercury loops • First version: muxed Keithley • Version 2.0: COTS preamp, 24 bit ADC per channel, EPICS integration Roberts, Pennisi, Freeman, Gallmier, ASD and XFD Controls Brown Bag, October 5, 2006
Target Viewscreen Data Analysis • non-linear geometric mapping to correct for optical distortion • Correction for viewscreen angle and offset with respect to target • BCM data used to provide pulse by pulse normalization. Produces plots of 2D particle distribution - (p/pulse)/mm^2 • Horizontal and vertical projection to compare with harp and wire scanner results. • Calculation and strip chart display of horizontal and vertical centroid and RMS width of beam distribution • About 800 GB of data collected. Manually moved some to enterprise network for collaborators to analyze. Manually transformed a few images to text for viewing and sharing. Local copy of Labview required. Metadata in file name. • Better way? Controls Brown Bag, October 5, 2006
Portal Architecture and Interfaces Steve Miller et al, SNS Science division Controls Brown Bag, October 5, 2006
Visualizing Data via the Portal – Data Browser MCA Data ISAW Plot NeXus tags NeXus Files metadata Controls Brown Bag, October 5, 2006
Target Viewscreen Hardware At 2MW, this is a nasty place to be Controls Brown Bag, October 5, 2006
Degradation due to radiation damage (fiber darkening) • Data taken from 5kW run (about 1.7E13 p/pulse at 2Hz) • Efficiency corrected for shutter width, beam intensity, exponential decay of photon signal • TVS1 shown; TVS2 far worse -> fiber darkening, not much screen damage • By end of run, lens and fiber tip received about a Gigarad dose Controls Brown Bag, October 5, 2006
Viewscreen 2.0 – view target nose from upstream Controls Brown Bag, October 5, 2006
Viewscreen 2.0 – reflective optical path McManamy, Sheldon, Development Division Controls Brown Bag, October 5, 2006
Viewscreen 2.0 – Mirror on Proton Beam Window Assembly Controls Brown Bag, October 5, 2006
Viewscreen 2.0 – Fiber routing Ron Sheldon, Development Division Controls Brown Bag, October 5, 2006
One option for Target Viewscreen 2.0Transition Radiation (no screen) predicted angular distribution of photons from SNS target noseOrders of magnitude less yield than phosphor Demo at low gamma:5keV electrons @ UMER Phosphor OTR Ralph Fiorito, Don Feldman, U. of Maryland Controls Brown Bag, October 5, 2006
Viewscreen 2.0 Summary • Glowing Tungsten Mesh (Near IR, based on Thomsen’s @ PSI) • Narrow dynamic range determined ahead of time by wire size. • Transition Radiation (Collaboration with Maryland) • Low intensity, but prompt • Thermal imaging (Long wavelength infrared, could also be used for injection electron catcher) • Issue for Viewscreen 2.0: can we transport these wavelengths? • Issue at injection: Rad hard IR camera? • Temporary phosphor screen • How long will it last? Failure modes, remote handling? Common Challenges:Helium background - orders of magnitude above OTR?Optical path <-> Radiation damage Status: Development approved; PO written to modify proton beam window ass’y; propose we host international workshop (US, Europe, Japan) and perform tests at SNS and LANL. Controls Brown Bag, October 5, 2006
Imaging in the RTBT • Test stand for Target Viewscreen technologies – install actuator with multiple screens • More robust way to measure beam tilt and other artifacts Controls Brown Bag, October 5, 2006
Imaging in the RTBT • Camera system could be nearly identical to decommissioned Target Viewscreen system, but cables need to run in tunnel and by extraction dump. Switch from Firewire on fiber to GigE vision on Cat6 copper. Controls Brown Bag, October 5, 2006
Neutron Beam Imaging • Similar to viewcreens for charged particle beams, can also create viewscreen system for neutron beams • Special scintillators available for low energy neutrons (i.e. Lithium glass). • Probability of capture is inversely proportional to velocity. About 8000 blue photons emitted for each captured neutron. Much higher yield scintillators also being considered. Controls Brown Bag, October 5, 2006
SANS Zhao, Billeaux, et. al. Controls Brown Bag, October 5, 2006
SANS Controls Brown Bag, October 5, 2006
SANS – detectors and beam stop Controls Brown Bag, October 5, 2006
SANS Transmission Monitor • Differential particle current measurement • Compare to He3 chamber upstream of sample • Smaller detector at dump (chamber won’t fit) • Equivalent frame rate: 60 kHz (to provide time/energy resolution and deconvolve energy dependent efficiency) • Project approved as part of the SANS instrument construction • Must be running summer 2007 – early test @ HIFR? • Similar imaging system with relaxed specs could be used to check beam on sample - many instrument groups have expressed interest Controls Brown Bag, October 5, 2006
Science Division Initiative:Polarized Neutrons – Why? J. K. Zhao, SNS Controls Brown Bag, October 5, 2006
Polarized Neutrons – How? 1970’s custom modules update w/COTS? J. K. Zhao, SNS and Don Crabb, University of Virginia Controls Brown Bag, October 5, 2006
Comparison: Accelerator and Polarized Target Technologies Controls Brown Bag, October 5, 2006
Single shot emittance measurement with Pepper Pot • Fast checkout of source. Minimize interruption of users program and limit thermal cycling of target. • Active development again at GSI, CERN, BNL • Possible as part of SNS power upgrade Controls Brown Bag, October 5, 2006
Help Needed in Several Areas • Camera evaluation (identify common requirements, assess interfaces like GigE) • Broadband optics design (LWIR through UV) • Analog electronics (NMR system) • Labview development (primarily imaging systems) • Assess applicability of Science division software • Explore common interface to EPICS, and instrument DAQ/Sample environment. Share virtually identical systems below that interface point. • A lot more where this came from… Controls Brown Bag, October 5, 2006
What do R&D staff want? Controls Brown Bag, October 5, 2006
Thank you Controls Brown Bag, October 5, 2006