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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Latest News
What’s the most difficult question you’ve been asked as a maintenance instructor?
Blye Widmar
"Where are the prints?!"
This was the final question in an onslaught of verbal feedback, comments, and critiques I received from my students back in 2019. I had two years of instructor experience and was teaching a class that had been meticulously rehearsed in preparation for an accreditation visit. I knew the training material well and transferred that knowledge effectively enough for all the students to pass the class. As we wrapped up, I asked the students how they felt about my first big system-level class, and they did not hold back.
“Why was the exam from memory when we don’t work from memory in the plant?” “Why didn’t we refer to the vendor documents?” “Why didn’t we practice more on the mock-up?” And so on.
Dan M. Goebel
Fusion Science and Technology | Volume 10 | Number 3 | November 1986 | Pages 761-769
Impurity Control | Proceedings of the Seveth Topical Meeting on the Technology of Fusion Energy (Reno, Nevada, June 15–19, 1986) | doi.org/10.13182/FST86-A24832
Articles are hosted by Taylor and Francis Online.
Particle removal from tokamak plasmas is essential to achieve density control and some measure of impurity control. This requirement can be satisfied by pump limiters, the present status of which is reviewed here. Modular experiments have recently achieved particle removal rates over 10 torr-1/sec. Studies of impurity removal by pump limiters have demonstrated He and N2 (moderate Z) exhaust. Successful modeling of the pump limiter performance using Monte-Carlo neutral gas codes has expanded the understanding of the physics of pump limiters. The heat flux to the surface of limiters in tokamaks has been studied in detail. The rapid progress in the engineering, theory, and experimental results of pump limiters has led to plans for the application of these devices in new experiments in the next few years.
