CYCLOTRONS 2010 - List of Authors (Rao, Y.-N.)

Paper

Title

Page

Reliable Production of Multiple High Intensity Beams with the 500 MeV TRIUMF Cyclotron

280

R.A. Baartman, F.W. Bach, I.V. Bylinskii, J.F. Cessford, G. Dutto, D.T. Gray, A. Hurst, K. Jayamanna, M. Mouat, Y.-N. Rao, W.R. Rawnsley, L.W. Root, R. Ruegg, V.A. Verzilov
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

In 2001, after 25 years of smooth cyclotron operation with up to ~200 μA H¯ acceleration, developments towards higher intensities became compelling because of the ISAC expansion. Recently average current of 300 μA, within a nominal ~90% duty cycle, was routinely achieved. Beam availability was 90-94% over the last five years. Development highlights are discussed in the paper. These include: ion source and beam transport re-optimized for this cyclotron acceptance; the 12 m long vertical injection line section was redesigned to accommodate higher space charge. In the centre region, a water cooled beam scraper was installed to absorb unwanted phases; other electrodes were realigned. Other activities were aimed at beam stability enhancement for ISAC. This included: reducing ν_r = 3/2 resonance effects at 420 MeV, stabilizing the intensity of the primary beam through pulser feedback regulation and improving beam quality at the target through beam optics optimization and target position stability feedback, etc. Extraction was also improved, using special stripping foils.

Slides TUM1CCO03 [1.882 MB]

THA1CCO04

Cyclotron and FFAG Studies Using Cyclotron Codes

395

M.K. Craddock
UBC & TRIUMF, Vancouver, British Columbia, Canada
Y.-N. Rao
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

This paper describes the use of cyclotron codes to study the beam dynamics of both high-energy isochronous cyclotrons using AG focusing and non-scaling (NS) FFAGs. The equilibrium orbit code CYCLOPS determines orbits, tunes and period at fixed energies, while the general orbit code GOBLIN tracks a representative bunch of particles through the acceleration process. The results for radial-sector cyclotrons show that the use of negative valley fields allows axial focusing to be maintained, and hence intense cw beams to be accelerated, to energies ≈10 GeV. The results for FFAGs confirm those obtained with lumped-element codes, and suggest that cyclotron codes will prove to be important tools for evaluating the measured fields of FFAG magnets.

Slides THA1CCO04 [1.750 MB]

Paper	Title	Page
TUM1CCO03	Reliable Production of Multiple High Intensity Beams with the 500 MeV TRIUMF Cyclotron	280
	R.A. Baartman, F.W. Bach, I.V. Bylinskii, J.F. Cessford, G. Dutto, D.T. Gray, A. Hurst, K. Jayamanna, M. Mouat, Y.-N. Rao, W.R. Rawnsley, L.W. Root, R. Ruegg, V.A. Verzilov TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	In 2001, after 25 years of smooth cyclotron operation with up to ~200 μA H¯ acceleration, developments towards higher intensities became compelling because of the ISAC expansion. Recently average current of 300 μA, within a nominal ~90% duty cycle, was routinely achieved. Beam availability was 90-94% over the last five years. Development highlights are discussed in the paper. These include: ion source and beam transport re-optimized for this cyclotron acceptance; the 12 m long vertical injection line section was redesigned to accommodate higher space charge. In the centre region, a water cooled beam scraper was installed to absorb unwanted phases; other electrodes were realigned. Other activities were aimed at beam stability enhancement for ISAC. This included: reducing ν_r = 3/2 resonance effects at 420 MeV, stabilizing the intensity of the primary beam through pulser feedback regulation and improving beam quality at the target through beam optics optimization and target position stability feedback, etc. Extraction was also improved, using special stripping foils.
	Slides TUM1CCO03 [1.882 MB]

THA1CCO04	Cyclotron and FFAG Studies Using Cyclotron Codes	395
	M.K. Craddock UBC & TRIUMF, Vancouver, British Columbia, Canada Y.-N. Rao TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	This paper describes the use of cyclotron codes to study the beam dynamics of both high-energy isochronous cyclotrons using AG focusing and non-scaling (NS) FFAGs. The equilibrium orbit code CYCLOPS determines orbits, tunes and period at fixed energies, while the general orbit code GOBLIN tracks a representative bunch of particles through the acceleration process. The results for radial-sector cyclotrons show that the use of negative valley fields allows axial focusing to be maintained, and hence intense cw beams to be accelerated, to energies ≈10 GeV. The results for FFAGs confirm those obtained with lumped-element codes, and suggest that cyclotron codes will prove to be important tools for evaluating the measured fields of FFAG magnets.
	Slides THA1CCO04 [1.750 MB]