For the production of hadronic particles for the CERN accelerator complex, two types of pulsed ion source are currently in use. Ions from these sources are preaccelerated before injection into the linacs. Protons are produced in a Duoplasmatron source, injected into Linac2 and accelerated to 50 MeV. Heavy Ions, currently lead208 27 times charged, are formed in an Electron Cyclotron Resonance (ECR) source for acceleration in Linac3 to 4.2 MeV/u.
| Type | Duoplasmatron with biased electrode in expansion cup |
| Source Body | Iron or mild steel acting as magnetic flux path |
| Intermediate electrode | Iron, water cooled. Forms cathode plasma chamber |
| I.E. Canal | 5 mm. diameter, 12 mm. long |
| Cathode | Mixed oxide thermionic, hairpin, 16 mm. by 92 mm. |
| Heating current | 50 A (150 W) via arc isolating transformer |
| Hydrogen flow | 3 - 6 atm.cc/min (0.05 - 0.1 mbar l/s) |
| Plasma chamber pressure | 0.7 - 2 mbar (estimated |
| Main (compression magnet) | 2 layer, water cooled, 10A (8750 A.T), iron return |
| Anode | 1 mm. molybdenum in iron insert |
| Anode hole | Typically 0.6 mm |
| Arc supply | Current controlled connected to cathode |
| Arc voltage | 500 - 1000 V ignition, 80 V during discharge |
| Arc current | 50 - 60 A pulsed |
| Pulse length | 20 - 150 us (by crowbar of delay line, user defined) |
| Repetition rate | 1 Hz |
| Expansion magnet | Encapsulated, Kapton/BN3/epoxy insulated (600 A.T) |
| Expansion cup | Titanium with pseudo-Pierce angle, 20 mm. aperture |
| Polarised electrode | Stainless steel held at -40 V wrt. expansion cup |
| Extraction | By acceleration field, accel - decel |
| Extraction potential | 92 kV (- 3kV on decel electrode) |
| Extraction gap | 16.5 mm |
| Beam current | 250 - 320 mA |
| Type | Electron Cyclotron Resonance (ECR) ECR4 |
| Frequency | 14.5 GHz |
| Resonance field | 0.52 Tesla |
| Plasma chamber | Water cooled stainless steel |
| Dimensions | 66 mm. diameter, 179 mm. long |
| Plasma electrode aperture | 16 mm |
| Cutoff plasma density | 2.4 1012 /cm3 |
| Longitudinal Confinement | Minimum B, mirror, 2 water cooled coils |
| Peak axial field | 1.1 Tesla |
| Mirror ratio | 2.2 |
| Coil current | typically 1100 A |
| Radial confinement | NdFeB permanent magnet hexapole |
| Pole tip field | 1.2 T but with longitudinal gradient |
| RF power | 2 kW max. |
| RF power source | Klystron amplifier |
| Power injection | Tuned waveguide to co-axial transition |
| Operation mode | Pulsed, optimised for "afterglow" |
| Sample feed | Gaseous, by injection through co-ax |
| Metallic, by micro-over or plasma heating | |
| Plasma Gas | Oxygen |
| Heating pulse length | 50 ms |
| Useful beam length | approximately 1 ms. |
| Repetition rate | 10 (5) Hz |
| Extraction | By acceleration field, one gap |
| Extraction potential | 2.5 keV/nucleon (nominal) |
| Extraction gap | 42 mm. |
| Beam currents | Total 2 -3 mA (typically) |
| Analysed, >100microA Pb27+ |