IPAC2013 - List of Authors (Stassen, R.)

Paper	Title	Page
MOPEA016	The Main Stochastic Cooling System of the HESR	100
	R. Stassen, R. Greven, R. Maier, G. Schug, H. Stockhorst FZJ, Jülich, Germany
	The main stochastic cooling system of the High-Energy Storage Ring HESR (1.5-15 GeV/c) for antiprotons at the FAIR complex (Facility for Antiprotons and Ion Research) in Darmstadt (GSI) will work in the frequency range of 2 - 4 GHz. The design work on pickup and kicker is now finished and the production of the first cooling tank has been started. The whole system layout will be presented taking into account new additional requirements concerning the accumulation and the cooling of heavy ions. All beam-coupling structures are nearly identical and contain several ring-slot blocks. These blocks consist of eight wall-current monitors coupled out by eight electrodes each. Most of the signal combining and splitting take place within the vacuum envelope to reduce the number of vacuum RF feed throughs. The long-distance transmission of the signals and the filters containing long signal delays work with near infrared optical elements.

MOPEA018	Feasibility Study of Heavy Ion Storage and Acceleration in the HESR with Stochastic Cooling and Internal Targets	106
	H. Stockhorst, R. Maier, D. Prasuhn, R. Stassen FZJ, Jülich, Germany T. Katayama GSI, Darmstadt, Germany
	Stochastic cooling of heavy ions is investigated under the constraint of the present hardware design of the cooling system and RF cavities as well as the given magnet design as foreseen for anti-proton cooling in the HESR of the FAIR facility. A bare uranium beam is injected from the collector ring CR into the HESR at 740 MeV/u. The beam preparation for an internal target experiment with cooling is outlined. The acceleration of the ion beam to 2 GeV/u is studied under the basic condition of the available cavity voltages and the maximum magnetic field ramp rate in the HESR. The cooling simulations include the beam-target interaction due to a Hydrogen and Xenon target. Diffusion due to Schottky and thermal noise as well as intra beam scattering is accounted for. Due to the higher charge states of the ions Schottky particle noise power becomes an important issue. The analysis considers the electronic power limitation to 500 W in case of momentum cooling. Fast Filter cooling is only available if the revolution harmonics do not overlap in the cooling bandwidth. Since overlap occurs for lower energies the application of the Time-Of-Flight (TOF) momentum cooling method is discussed.

Paper

Title

Page

The Main Stochastic Cooling System of the HESR

100

R. Stassen, R. Greven, R. Maier, G. Schug, H. Stockhorst
FZJ, Jülich, Germany

The main stochastic cooling system of the High-Energy Storage Ring HESR (1.5-15 GeV/c) for antiprotons at the FAIR complex (Facility for Antiprotons and Ion Research) in Darmstadt (GSI) will work in the frequency range of 2 - 4 GHz. The design work on pickup and kicker is now finished and the production of the first cooling tank has been started. The whole system layout will be presented taking into account new additional requirements concerning the accumulation and the cooling of heavy ions. All beam-coupling structures are nearly identical and contain several ring-slot blocks. These blocks consist of eight wall-current monitors coupled out by eight electrodes each. Most of the signal combining and splitting take place within the vacuum envelope to reduce the number of vacuum RF feed throughs. The long-distance transmission of the signals and the filters containing long signal delays work with near infrared optical elements.

MOPEA018

Feasibility Study of Heavy Ion Storage and Acceleration in the HESR with Stochastic Cooling and Internal Targets

106

H. Stockhorst, R. Maier, D. Prasuhn, R. Stassen
FZJ, Jülich, Germany
T. Katayama
GSI, Darmstadt, Germany

Stochastic cooling of heavy ions is investigated under the constraint of the present hardware design of the cooling system and RF cavities as well as the given magnet design as foreseen for anti-proton cooling in the HESR of the FAIR facility. A bare uranium beam is injected from the collector ring CR into the HESR at 740 MeV/u. The beam preparation for an internal target experiment with cooling is outlined. The acceleration of the ion beam to 2 GeV/u is studied under the basic condition of the available cavity voltages and the maximum magnetic field ramp rate in the HESR. The cooling simulations include the beam-target interaction due to a Hydrogen and Xenon target. Diffusion due to Schottky and thermal noise as well as intra beam scattering is accounted for. Due to the higher charge states of the ions Schottky particle noise power becomes an important issue. The analysis considers the electronic power limitation to 500 W in case of momentum cooling. Fast Filter cooling is only available if the revolution harmonics do not overlap in the cooling bandwidth. Since overlap occurs for lower energies the application of the Time-Of-Flight (TOF) momentum cooling method is discussed.