Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for t

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Approach to improving precision on RHEPP

• HAPL Concerns for RHEPP
• Present variation of fluence at a fixed location
• Approach to improving precision

Craig Olson Sandia National Laboratories Albuquerq
ue, NM 87185
HAPL Workshop LLNL June 20-21, 2005
Supported by NRL by the HAPL program by DOE NNSA
DP
Sandia is a multiprogram laboratory operated by
Sandia Corporation, a Lockheed Martin
Company,for the United States Department of
Energy under contract DE-AC04-94AL85000.
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HAPL Concerns for RHEPP
Question Concern
Status Approach
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Pulsed Power Sciences, Sandia National
Laboratories TJR 11/25/03
RHEPP-1 Surface Roughening
Range of Fluences, MaxTemps (W) for RHEPP-1
TEMP simulations (SIM CODE) Based on Fcups (Room
Temp)
Fcups averaged over 10 or 40 pulses
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Approach to improving precision on RHEPP

• Analyze existing exposed samples for impurities
• (such as WN, WC, poor vacuum,
  cross-contamination of other samples, sticky
  tape, etc.)
• Perform Experiment to validate existing data
• use only one sample (W)
• clean chamber as well as possible
• center sample at center of machine
  (R 0) with metal clamp
• attenuate fluence to desired value (
  ? 1 J/cm2)
• monitor every shot (Faraday cup) for
  max fluence
  
• perform many shot run
• analyze impurities (e.g., N, C, ) on sample (if
  any)
• compare to existing data (with
  multiple samples, sticky tape, C, etc.)
• Obtain higher-precision data
• (i) add temperature thermometer
  (UCSD)
• (ii) improve chamber conditions
  if above experiment indicates need
• (e.g., cleaner, less
  plastic feed-throughs, better vacuum, etc.)
• (iii) establish source of
  fluence fluctuations
• (e.g., is it gas puff
  source, plasma source location, non-uniformity