Changelog
A dated record of what changed on this site: content additions, data updates, and substantive corrections, newest first. How the content itself is produced is documented in the editorial methodology. This log begins with the site’s 4 October 2026 edition; records of earlier revisions are retained internally.
- — Four of the hosted "Notes on the Mullins Mark I Cyclotron" are revised to their builder's September 2026 editions, each opening with a dated revision note: the RF/dee/ion-source note gains the builder's direct RF-system measurements (terminal capacitance, loaded Q, and the component table behind them — with dee voltage still stated as unmeasured), and the simulation-models note withdraws its earlier stem and feedthrough capacitance-by-subtraction statements. The instrumentation and performance notes carry the same revision box; page counts on the collection page update with the files. The series remains CC BY 4.0 under its author's name.
- — The worldwide cyclotron directory is live: 1,564 machines in 92 countries on a filterable map and list — identity, location at stated precision, category, current status, technical class, verification date, and public-tour availability with each facility's own tour link. The directory is published as a dated quarterly edition (this one: 4 October 2026), and every census-derived figure on the site computes from it, so the whole site shares one as-of. The data is downloadable as JSON or CSV under CC BY-NC 4.0; the Design Guide and bibliography exports are CC BY 4.0. Every record is verified against public sources, which are retained and available to researchers on request.
Spotted an error, a dead link, or an out-of-date claim? Corrections are welcome at info@cyclotroninfo.com — fixes are made in place and noted here.