Charged particle accelerator

A charged particle accelerator comprising a charged particle generating apparatus, a bending magnet, accelerating means and a vacuum duct, characterized in that charged particles injected from the charged particle generating apparatus into the vacuum duct are bent by the bending magnet and accelerated to have prescribed energy after passing through a first acceleration period and a second acceleration period, a beam extraction period linked to the second acceleration period is provided, electric field generated by the accelerating means is applied from the start time of the first acceleration period until the end time of the extraction period, and magnetic field generated by the bending magnet is applied at a fixed value during the first acceleration period, the magnetic field is increased until the end time of the second acceleration period during the second acceleration period, and the magnetic field is set to a terminal value of the second acceleration period which is kept constant during the extraction period.

A charged particle accelerator comprising a charged particle generating apparatus, a bending magnet, accelerating means and a vacuum duct, characterized in that charged particles injected from the charged particle generating apparatus into the vacuum duct are bent by the bending magnet and accelerated to have prescribed energy after passing through a first acceleration period and a second acceleration period, electric field generated by the accelerating means is applied from the start time of the first acceleration period until the end time of the second acceleration period, magnetic field generated by the bending magnet is applied so as to increase from the acceleration start time of the first acceleration period until the end time of the second acceleration period, and the energy of the charged particles emitted from the charged particle generating apparatus in the first acceleration period is varied.