Field of Interest:physics.acc-phys
Deadline: 2016-07-31
Region: Europe
Job description:
The research entails novel cavity structures that can be the basis for a two-beam, high-gradient, accelerator. These structures feature the anode-cathode effect (in which the particles are preferentially directed towards the metallic walls), multi-harmonic operation, and collinear beams. All structures are detuned, such that a energy transfer ratio substantially larger than two is envisaged. Versions of the structure could be used for acceleration of beams of electrons, positrons, muons, protons, or heavier ions; with either electron or proton drive beams. The structure embodies cavities that are excited in several harmonically related eigenmodes, such that rf fields reach their peak values only during small portions of each basic rf period. This feature could help raise breakdown and pulse heating thresholds. The two-beam accelerator structure comprises chains of these cavities. In this configuration, no transfer elements are needed to couple rf energy from the drive beam to the accelerated beam, since both beams traverse the same cavities. Purposeful cavity detuning is used to provide much smaller deceleration for a high-current drive beam, than acceleration for a low-current accelerated beam, i.e., to provide a high transformer ratio. A self-consistent theory will be analysed by the student to calculate idealized acceleration gradient, transformer ratio, and efficiency for energy transfer from the drive beam to the accelerated beam, for either parallel or antiparallel motion of the beams.
These cavities have application to linear colliders, medical accelerators for the production of high-energy protons or electrons. There is also the potential for utilising these in light sources, cargo scanning and related industrial applications.
More Information:http://www.hep.man.ac.uk/u/rmj/TBA_PHD.pdf
Deadline: 2016-07-31
Region: Europe
Job description:
The research entails novel cavity structures that can be the basis for a two-beam, high-gradient, accelerator. These structures feature the anode-cathode effect (in which the particles are preferentially directed towards the metallic walls), multi-harmonic operation, and collinear beams. All structures are detuned, such that a energy transfer ratio substantially larger than two is envisaged. Versions of the structure could be used for acceleration of beams of electrons, positrons, muons, protons, or heavier ions; with either electron or proton drive beams. The structure embodies cavities that are excited in several harmonically related eigenmodes, such that rf fields reach their peak values only during small portions of each basic rf period. This feature could help raise breakdown and pulse heating thresholds. The two-beam accelerator structure comprises chains of these cavities. In this configuration, no transfer elements are needed to couple rf energy from the drive beam to the accelerated beam, since both beams traverse the same cavities. Purposeful cavity detuning is used to provide much smaller deceleration for a high-current drive beam, than acceleration for a low-current accelerated beam, i.e., to provide a high transformer ratio. A self-consistent theory will be analysed by the student to calculate idealized acceleration gradient, transformer ratio, and efficiency for energy transfer from the drive beam to the accelerated beam, for either parallel or antiparallel motion of the beams.
These cavities have application to linear colliders, medical accelerators for the production of high-energy protons or electrons. There is also the potential for utilising these in light sources, cargo scanning and related industrial applications.
More Information:http://www.hep.man.ac.uk/u/rmj/TBA_PHD.pdf