A method for the suppression of upstream-directed field emission in RF accelerators. The method is not restricted to a certain number of cavity cells, but requires similar operating field levels in all cavities to efficiently annihilate the once accumulated energy. Such a field balance is desirable to minimize dynamic RF losses, but not necessarily achievable in reality depending on individual cavity performance, such as early Q.sub.0-drop or quench field. The method enables a significant energy reduction for upstream-directed electrons within a relatively short distance. As a result of the suppression of upstream-directed field emission, electrons will impact surfaces at rather low energies leading to reduction of dark current and less issues with heating and damage of accelerator components as well as radiation levels including neutron generation and thus radio-activation.

A method for the suppression of upstream-directed field emission in RF accelerators. The method is not restricted to a certain number of cavity cells, but requires similar operating field levels in all cavities to efficiently annihilate the once accumulated energy. Such a field balance is desirable to minimize dynamic RF losses, but not necessarily achievable in reality depending on individual cavity performance, such as early Q.sub.0-drop or quench field. The method enables a significant energy reduction for upstream-directed electrons within a relatively short distance. As a result of the suppression of upstream-directed field emission, electrons will impact surfaces at rather low energies leading to reduction of dark current and less issues with heating and damage of accelerator components as well as radiation levels including neutron generation and thus radio-activation.

Systems and methods for that utilize a compressed coherent high intensity X-ray pulse to drive acceleration of particles in a solid medium laser wakefield accelerator (LWFA).

Systems and methods for that utilize a compressed coherent high intensity X-ray pulse to drive acceleration of particles in a solid medium laser wakefield accelerator (LWFA).

Provided are a plurality of embodiments, including, but not limited to, a device for generating efficient low and high average power output Gamma Rays via relativistic particle bombardment of element targets using an efficient particle injector and accelerator at low and high average power levels suitable for element transmutation and power generation with an option for efficient remediation of radioisotope release into any environment. The devices utilize diamond or diamond-like carbon materials and active cooling for improved performance.

Provided are a plurality of embodiments, including, but not limited to, a device for generating efficient low and high average power output Gamma Rays via relativistic particle bombardment of element targets using an efficient particle injector and accelerator at low and high average power levels suitable for element transmutation and power generation with an option for efficient remediation of radioisotope release into any environment. The devices utilize diamond or diamond-like carbon materials and active cooling for improved performance.

A photocathode comprises a substrate in which a cavity is formed and a film of material disposed on the substrate. The film of material comprises an electron emitting surface configured to emit electrons when illuminated by a beam of radiation. The electron emitting surface is on an opposite side of the film of material from the cavity.

A photocathode comprises a substrate in which a cavity is formed and a film of material disposed on the substrate. The film of material comprises an electron emitting surface configured to emit electrons when illuminated by a beam of radiation. The electron emitting surface is on an opposite side of the film of material from the cavity.

A synchrotron injector system comprising a first ion source which generates a first ion, a second ion source which generates a second ion having a smaller charge-to-mass ratio than a charge-to-mass ratio of the first ion, a pre-accelerator having the capability to enable to accelerate both the first ion and the second ion, a low-energy beam transport line which is constituted in such a way to inject either the first ion or the second ion into the pre-accelerator, and a self-focusing type post-accelerator which accelerates only the first ion after acceleration which is emitted from the pre-accelerator.

A synchrotron injector system comprising a first ion source which generates a first ion, a second ion source which generates a second ion having a smaller charge-to-mass ratio than a charge-to-mass ratio of the first ion, a pre-accelerator having the capability to enable to accelerate both the first ion and the second ion, a low-energy beam transport line which is constituted in such a way to inject either the first ion or the second ion into the pre-accelerator, and a self-focusing type post-accelerator which accelerates only the first ion after acceleration which is emitted from the pre-accelerator.