May 28 2025 Madison WI
This single day workshop focused on neutrals and impurities in laboratory plasmas. Managing both well enough to achieve good results is not trivial, especially on medium scale experiments.
The four UW fusion experiments of HSX, Pegasus, MST, and WHAM have independently developed their own systems for achieving good vacuum and impurity hygiene. In doing so, each group has accumulated their own institutional knowledge. Such specific information is rarely considered worthy of publishing in plasma physics journals, to our collective detriment.
The goal of this workshop was to document and share these hard-won learnings. Representatives from each experiment summarized the historical development of their group’s systems and procedures, discussions followed.
Vacuum and neutrals
WHAM-Kunal Sanwalka: Vessel Conditioning Made Me Lose My Hair
HSX-Alexis Wolfmeister:Just Install a Baking System Already !
Pegasus – Sophie Redd: Pegasus-III Vacuum and Neutrals: Titanium is addicting
MST-Patrick Tracy:“A leak is a leak”: Vacuum Integrity in the Madison Symmetric Torus
Dominant impurity species and challenges
WHAM-Mason Yu:How To Make a Blue Plasma: Impurities in WHAM
MST-Joe Flahavan:Get out of my walls! : Impurity ions in MST
HSX-Thomas Gallenberger:HSX Vacuum system and practices
Pegasus-Temo Rodriguez Sanchez: Local Helicity (Impurity?) Injection in Pegasus
Discussions: Doug Endrizzi notes