A permanent magnet microwave ion source with adjustable magnetic field is developed at China Institute of Atomic Energy.The magnetic field in the region of ionization chamber is generated by permanent magnets.Outside ...A permanent magnet microwave ion source with adjustable magnetic field is developed at China Institute of Atomic Energy.The magnetic field in the region of ionization chamber is generated by permanent magnets.Outside the magnet,an iron yoke is installed to adjust the magnetic field,and the yoke can be adjusted easily by hands.With adjustable magnetic field,the ion source can be tuned into the optimized operational condition.From an aperture of 3mm in diameter,17mA hydrogen beam has been extracted.展开更多
With the calculation and measuring experiment methods,the effect of vacuum chamber materials' magnetic permeability on field distribution in a dipole magnet is discussed.The results show that when the relative mag...With the calculation and measuring experiment methods,the effect of vacuum chamber materials' magnetic permeability on field distribution in a dipole magnet is discussed.The results show that when the relative magnetic permeability of chamber materialμ_r≠1,it will affect the field uniformity.Once the high field uniformity is required, the material property and size of vacuum chamber in a dipole magnet have to be taken into account carefully.展开更多
In order to extract parallel beam from ion sources,it's necessary to design suitable electrode configurations in extraction zone.Taking the effect of the space-charge into account,the electrode configurations shou...In order to extract parallel beam from ion sources,it's necessary to design suitable electrode configurations in extraction zone.Taking the effect of the space-charge into account,the electrode configurations should vary with beam current density.A means of calculating extraction configuration of parallel beam with certain current density has been evolved from the space-charge limited current.By solving Poisson equation and Laplace equation,the potential distribution close to the strip beam has been gotten.展开更多
文摘A permanent magnet microwave ion source with adjustable magnetic field is developed at China Institute of Atomic Energy.The magnetic field in the region of ionization chamber is generated by permanent magnets.Outside the magnet,an iron yoke is installed to adjust the magnetic field,and the yoke can be adjusted easily by hands.With adjustable magnetic field,the ion source can be tuned into the optimized operational condition.From an aperture of 3mm in diameter,17mA hydrogen beam has been extracted.
文摘With the calculation and measuring experiment methods,the effect of vacuum chamber materials' magnetic permeability on field distribution in a dipole magnet is discussed.The results show that when the relative magnetic permeability of chamber materialμ_r≠1,it will affect the field uniformity.Once the high field uniformity is required, the material property and size of vacuum chamber in a dipole magnet have to be taken into account carefully.
文摘In order to extract parallel beam from ion sources,it's necessary to design suitable electrode configurations in extraction zone.Taking the effect of the space-charge into account,the electrode configurations should vary with beam current density.A means of calculating extraction configuration of parallel beam with certain current density has been evolved from the space-charge limited current.By solving Poisson equation and Laplace equation,the potential distribution close to the strip beam has been gotten.
