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Harmonic Number Jump in a Ring with Cavities Distributed Everywhere.

DE2007910368

Publication Date	2007
Personal Author	Berg, J. S.
Page Count	10
Abstract	One of the primary motivations for using fixed field alternating gradient accelerators (FFAGs) is their ability to accelerate rapidly, since the magnetic fields do not need to be varied. However, one must then face the difficulty that the time of flight in an FFAG depends strongly on the particle energy. Traditionally, this is dealt with by varying the RF frequency. The rate at which one can vary the RF frequency is limited, and a cavity and power source which have a rapidly varying RF frequency are costly. One solution to this is harmonic number jump acceleration (Alessandro G. Ruggiero, Phys. Rev. ST Accel. Beams 9, 100101 (2006)), where the RF frequency is fixed. The RF frequency is chosen so that each turn has an integer number of RF periods, but that integer number is different on each turn. When accelerating rapidly, a large number of cavities is often required. This paper will show that in general, the time of flight can only be an integer number of RF periods for all turns at one position in the ring. It will then compute how well one can do when cavities are distributed everywhere in the ring. The paper will show some examples, and will discuss possible applications for this technique.
Keywords	Accelerators Beam acceleration Equations Single cavities RF frequency Harmonic number jump acceleration Fixed field alternating gradient accelerator (FFAG) Time of flight Approximate phase matching
Source Agency	Technical Information Center Oak Ridge Tennessee
Corporate Authors	Brookhaven National Lab., Upton, NY. Physics Dept.; Department of Energy, Washington, DC.
Supplemental Notes	Sponsored by Department of Energy, Washington, DC.
Document Type	Technical Report
NTIS Issue Number	200726

Harmonic Number Jump in a Ring with Cavities Distributed Everywhere.

Harmonic Number Jump in a Ring with Cavities Distributed Everywhere.
DE2007910368

Publication Date	2007
Personal Author	Berg, J. S.
Page Count	10
Abstract	One of the primary motivations for using fixed field alternating gradient accelerators (FFAGs) is their ability to accelerate rapidly, since the magnetic fields do not need to be varied. However, one must then face the difficulty that the time of flight in an FFAG depends strongly on the particle energy. Traditionally, this is dealt with by varying the RF frequency. The rate at which one can vary the RF frequency is limited, and a cavity and power source which have a rapidly varying RF frequency are costly. One solution to this is harmonic number jump acceleration (Alessandro G. Ruggiero, Phys. Rev. ST Accel. Beams 9, 100101 (2006)), where the RF frequency is fixed. The RF frequency is chosen so that each turn has an integer number of RF periods, but that integer number is different on each turn. When accelerating rapidly, a large number of cavities is often required. This paper will show that in general, the time of flight can only be an integer number of RF periods for all turns at one position in the ring. It will then compute how well one can do when cavities are distributed everywhere in the ring. The paper will show some examples, and will discuss possible applications for this technique.
Keywords	Accelerators Beam acceleration Equations Single cavities RF frequency Harmonic number jump acceleration Fixed field alternating gradient accelerator (FFAG) Time of flight Approximate phase matching
Source Agency	Technical Information Center Oak Ridge Tennessee
Corporate Authors	Brookhaven National Lab., Upton, NY. Physics Dept.; Department of Energy, Washington, DC.
Supplemental Notes	Sponsored by Department of Energy, Washington, DC.
Document Type	Technical Report
NTIS Issue Number	200726