ESATSE Tritium Monitoring

1
Top level overview of target injection and
tracking tasks
Presented by Dan Goodin at the
High Average Power Laser Program
WorkshopPrinceton Plasma Physics
LaboratoryOctober 27 and 28, 2004
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Summary - target injection, tracking, and beam
steering

• What is target injection and tracking?
• What are the basic requirements?
• What are the issues to be addressed?
• Whats being done?

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Phase I injection/tracking/steering tasks
Phase I goals for target injection and tracking

• Build an injector that accelerates targets to a
  velocity to traverse the chamber (6.5 m) in 16
  milliseconds or less.
• Demonstrate target tracking with sufficient
  accuracy for a power plant (/- 20 microns).

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Injection, tracking, steering requirements are
challenging
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3
R 7 m T 1500 C

• Inject about 500,000 targets per day (6 Hz) for
  1000 MW(e)
• High velocity - 400 m/s, separable sabot for
  handling/accelerating
• Acceleration limited to about 1000 gs (for
  real cryo target, TBC)
• Need membrane support to avoid point-loading of
  target
• Reliable, repetitive placement to ?5 mm
• Direct drive tracking and beam steering to ?20 ?m
• Integration of tracking beam steering
  (reference system)

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What are the issues and whats being done?

• We have demonstrated with the gas-gun
• Rep-rated operation (6 Hz, burst mode)
• Two-piece sabot separation and deflection
• Membrane support of target in sabot
• Injection velocity of 400 m/s
• Time jitter at chamber center of 0.5 ms
• In-flight tracking
• Target placement accuracy at one sigma of 10 mm

• 1) Showing a method to repetitively inject
  targets at high velocity
• Gas gun demo
• Advanced injection methods (EM injector)
• 2) Showing in-flight tracking to ?20 ?m
• Ex-chamber tracking demo
• Develop in-chamber tracking methods

Sabot separation at 400 m/s
Evaluating/testing electromagnetic,
non-contacting coil gun design for the future
Approximately 25 meter length reflects SOMBRERO
plant fueling layout
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What are the issues and whats being done
(continued)?

• 3) Showing how to integrate the tracking and beam
  steering systems
• Conceptual designs and analyses
• 4) Showing target survival during the injection
  process
• Modeling of DT heatup during injection
• Modeling of DT response to heatup
• Experiments with rapid DT heatup
• Measurements of DT strength

Reference sphere to define target chamber center
Design of cell for measuring strength of DT (2mm
X 2mm view)
Chamber conditions affect heatup and tracking
DT cell for rapid heatup testing
Simulation of 18K target entering 4000K chamber
gas
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The presentations deal directly with these
issues
Talks in this session 1) Target survival during
injection - René Raffray 2) Target injection
issue, background gas and plasma - David
Harding 3) In-chamber tracking and integration
with beam steering - Graham Flint 4) Status of
target injection experiments - Dan Frey 5) Status
of target tracking experiments - Ron Petzoldt
In-flight tracking at 400 m/s
Injection experiment setup to simulate
full-length of Sombrero fueling