Research Needs for Magnetic Fusion Energy Sciences - US Burning ...

to highlight the research needs of measurements and diagnostics for burning plasmas we assessed
their urgency and magnitude. These are summarized in table 1, which also illustrates
the magnitude of the steps to be taken when moving from present-day diagnostic capabilities,
through iteR, to a demo device.
in organizing the research opportunities and requirements for making the necessary measurements
on steady-state burning plasmas, we have condensed the measurement sub-issues into the
following three areas (just as was done when considering these issues within Theme 1):
• development of the Measurement Capabilities needed for physics understanding of
issues crucial for the achievement of burning plasmas.
• development of the necessary Compatibility of the Measurements, Calibration
Strategies, and Reliability Requirements with the expected difficult environment.
• development of the necessary degree of real-time interpretation and analysis of the
measurements to facilitate the needed level of plasma control.
Research Opportunity — Development of the measurement capabilities needed for
physics understanding of issues crucial for the achievement of burning plasmas. This research
opportunity is covered in chapter 1 and will not be repeated here.
Research Opportunity — Development of the necessary compatibility of the measurements,
calibration strategies, and reliability requirements with the expected difficult
environment. This opportunity is the most challenging. as has been pointed out, the near-plasma
environment will be much more extreme than that of iteR, and, while the iteR program is
crucial for proceeding to demo, satisfying iteR needs will not solve longer-term demo concerns.
The primary role for diagnostics in a demo is device safety, plasma control for operation, and wall
protection. Robust control with compatible sensors is a prerequisite. We anticipate that demo
operational scenarios will be relatively invariant, perhaps reducing the ranges of parameters for
diagnostic coverage. The research opportunities in this area are:
• Research to define minimum set of measurement requirements for DEMO control and safety
— While this will depend somewhat on the operation scenario, an approximate set of
measurement requirements can be generated prior to the specification of the scenario.
This will guide needed research for making specific measurements. in some cases, the
need for research to develop new measurement capability is clear already. in other words,
there are some measurements for which we already know that present techniques will not
transfer to a demo. Thus, we also propose the efforts in the next bullet.
• Systematic research and development for those measurements for which present techniques
are not transferable to the steady-state high-performance burning plasma environment —
examples of these measurement areas include steady-state magnetics measurements, light
extractors, first-wall and blanket instrumentation, monitors for internal components,
and first-wall erosion monitors. keep in mind that the lifetime estimate for conventional
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