![Page 1: Lab Course: Ion Sources - Institute for Structure and Nuclear](https://reader031.vdocument.in/reader031/viewer/2022012011/613d2b2f736caf36b75a20cd/html5/thumbnails/1.jpg)
Lab Course: Ion Sources
Larry LammResearch Professor
Technical Director of the NSLWinter 2008
![Page 2: Lab Course: Ion Sources - Institute for Structure and Nuclear](https://reader031.vdocument.in/reader031/viewer/2022012011/613d2b2f736caf36b75a20cd/html5/thumbnails/2.jpg)
Accelerators in the lab
• Van de Graaff accelerators– KN (3.7 MV) and JN (1.5 MV) are “single-
ended”, meaning the ion source is inside the terminal, producing positively charged beams.
– FN (10.6 MV) is a “tandem” accelerator, with the terminal electrode in the center of the accelerator, requiring negatively charged beams external to the accelerator.
![Page 3: Lab Course: Ion Sources - Institute for Structure and Nuclear](https://reader031.vdocument.in/reader031/viewer/2022012011/613d2b2f736caf36b75a20cd/html5/thumbnails/3.jpg)
AcceleratorsFN (10.6 MV)
KN (3.7 MV) JN (1.5 MV)
![Page 4: Lab Course: Ion Sources - Institute for Structure and Nuclear](https://reader031.vdocument.in/reader031/viewer/2022012011/613d2b2f736caf36b75a20cd/html5/thumbnails/4.jpg)
Helium Ion Source (HIS)
• Produces negatively charged 3He and 4He beams for injection into the FN Tandem Van de Graaff accelerator.
![Page 5: Lab Course: Ion Sources - Institute for Structure and Nuclear](https://reader031.vdocument.in/reader031/viewer/2022012011/613d2b2f736caf36b75a20cd/html5/thumbnails/5.jpg)
• The heart of the HIS helium ion source is the duoplasmatron, manufactured by Peabody Scientific. The details of ion beam production within the duoplasmatron are a bit complicated, but the basic idea can be simply described.
Helium Ion Source (HIS)
![Page 6: Lab Course: Ion Sources - Institute for Structure and Nuclear](https://reader031.vdocument.in/reader031/viewer/2022012011/613d2b2f736caf36b75a20cd/html5/thumbnails/6.jpg)
Helium Ion Source• Filament
Legs (Ni) used to supply high current (60A) to Filament (W)
Filament Legs (Ni)
Filament (W)
![Page 7: Lab Course: Ion Sources - Institute for Structure and Nuclear](https://reader031.vdocument.in/reader031/viewer/2022012011/613d2b2f736caf36b75a20cd/html5/thumbnails/7.jpg)
Helium Ion Source• The
filament is surrounded by low pressure helium gas (3He or 4He)
Low Pressure Gas (He)
![Page 8: Lab Course: Ion Sources - Institute for Structure and Nuclear](https://reader031.vdocument.in/reader031/viewer/2022012011/613d2b2f736caf36b75a20cd/html5/thumbnails/8.jpg)
Helium Ion Source• The
filament glows white hot, emitting electrons which ionize the helium gas.
Filament (W)
![Page 9: Lab Course: Ion Sources - Institute for Structure and Nuclear](https://reader031.vdocument.in/reader031/viewer/2022012011/613d2b2f736caf36b75a20cd/html5/thumbnails/9.jpg)
Helium Ion Source• Solenoidal
magnet field helps focus electrons to enhance the plasma production.
Solenoid Magnet
![Page 10: Lab Course: Ion Sources - Institute for Structure and Nuclear](https://reader031.vdocument.in/reader031/viewer/2022012011/613d2b2f736caf36b75a20cd/html5/thumbnails/10.jpg)
Helium Ion Source• Positively
charged helium ions are “pulled”out of the source through a small aperture.
Beam Aperture