Learn

Everything on this site — the design rules, the calculators, the build census — rests on a small body of physics and eighty-plus years of accumulated practice. This section lays that foundation out in order: how the machine works, where it came from, what it is used for, what can hurt you, and what it realistically takes to build one.

These pages are editorial synthesis. They take a position, put a subsystem in a reading order, and cite the Design Guide rule behind each claim; the Design Guide itself is the evidence layer, where every rule keeps its verbatim quote and the page it came from. Follow a citation whenever a claim here matters to a decision.

The pages form a learning path and are best read in sequence, but each stands alone. Anyone considering a build should read Safety in full, whatever else they skip.

Start with the honest question: Should you build one at all? — the case against, argued in full, before the course begins. Decided to proceed? Choosing Your Machine turns a purpose into an energy band and a design point, with a project brief for each.

1 How a Cyclotron Works

The physics from first principles: the Lorentz force, the resonance condition, dees and RF, focusing, and why classical machines top out — plus how cyclotrons relate to linacs, betatrons, and synchrotrons.
2 History

From a sketch on a library evening in 1929 to the 4-inch prototype, the MeV barrier, the 184-inch synchrocyclotron, the isochronous era, and today’s superconducting and medical machines.
3 Applications

What cyclotrons actually do all day: PET and SPECT isotope production, the Tc-99m story, proton therapy, PIXE analysis, nuclear physics research, and more.
4 Safety

The hazards of small accelerator projects — high voltage, RF, X-rays, activation, vacuum, magnets, gas handling — each with its mechanism and its mitigation. Read before building anything.
5 So You Want to Build One

The honest starter path: the skills it takes, what documented builds actually cost, how long they take, how often they finish, the key design decisions, and where to ask questions.
6 Free Modeling & Simulation Tools

A verified catalog of free software for every design question — magnet field solvers, beam tracking, ion source extraction, RF, vacuum, and shielding — with honest assessments for tabletop builders.
7 Cyclotron Glossary

The reference to keep open alongside everything else: 90-odd concise definitions of the terms in cyclotron literature — anatomy, beam physics, RF, vacuum, safety, and regulation — each deep-linkable and cross-referenced.
8 The Cyclotron Industry

Who actually builds commercial cyclotrons: the current manufacturers worldwide with their machine lines, the historical makers whose nameplates survive on running machines, honest install-base numbers, and what working in the field looks like.
9 Keep Going: External Resources

Where the learning continues beyond this site — verified video courses and lecture archives, free conference proceedings, open textbooks, thesis collections, communities, and surplus vendors.

Deep dives

Unnumbered, and deeper than the path goes: one topic each, built from the Design Guide rules and the hosted construction classics.

Cyclotron Magnet Design

How to design, build, and correct the magnet: iron circuit, coils, model-first method, measurement, shimming.
Ion Sources for Small Cyclotrons

Filament, hooded-arc, and PIG anatomy; slit design, gas feed, arc behavior, species choice.
The Vacuum Budget of a Cyclotron

Pressure target from beam survival, the ion source as gas load, effective speed and the dee interior, pump trade-offs, a worked budget.
Driving the Dee: RF Coupling

Self-excited vs driven, loop vs capacitive coupling, discharge cures, measuring dee voltage.
Beam Measurement and Beam Quality

Proving first beam: cups that read true, pA electrometry, resonance signatures, beam-quality numbers.
Beam Quality

Phase space and emittance made concrete: what sets the beam you get, and what degrades it.
Beam Dynamics: An Interactive Laboratory

Betatron oscillations and field imperfections, live: adjust n, dial in errors, and recreate the 1947 beam loss.
Beam Extraction

Turn separation, deflectors and septa, precession, stripping — and why no documented amateur machine has run an external beam.
Shielding a Small Cyclotron

Which radiation a sub-MeV machine can physically produce, why the spectrum decides the material, and why shields leak at their penetrations.
Experiments by Energy Band

What a proton beam can physically do at 5–25 through 500–1000 keV — worked count rates at nanoamp currents.
Choosing Your Machine

Purpose first, then energy band, then the design point — per-band project briefs with the documented builds closest to each.

Off the path: An Entirely Objective Comparison of Particle Accelerators — satire, with the physics intact.