IPAC2013 - List of Authors (Maier, 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.

MOPEA017	Electron Cooling of Heavy Ions Interacting with Internal Target at HESR of FAIR	103
	T. Katayama, M. Steck GSI, Darmstadt, Germany R. Maier, D. Prasuhn, H. Stockhorst FZJ, Jülich, Germany
	The High Energy Storage Ring (HESR) is designed and optimized to accumulate and store the anti-proton beam for the internal target experiment. The recent demand of atomic physics has impacted to use the HESR facility also as the storage ring of bare heavy ions. In this concept the bare heavy ions are injected at 740 MeV/u from the Collector Ring where the ions are well stochastically cooled to be matched with HESR ring acceptance. In the HESR the 2 MeV electron cooler is prepared with the maximal electron current of 3 A and the cooling length of 2.7 m. The electron cooling process of typically ²³⁸U⁹²⁺ beam is simulated for the Hydogen and Xe internal target with simultaneous use of barrier voltage to compensate the mean energy loss caused by the interaction with internal target. In the present report the detailed simulation results of 6D phase space obtained by the particle tracking code are precisely discussed.

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.

WEPEA036	Spin Tune Decoherence Effects in Electro- and Magnetostatic Structures	2579
	Y. Senichev, R. Maier, D. Zyuzin FZJ, Jülich, Germany N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia
	In Electric Dipole Moment search experiments with polarized beams the coherence of spin oscillations of particles has a crucial role. The decoherent effects arise due to spin tune dependence on particle energy and particle trajectory in focusing-deflecting fields. They are described through the n-th order spin tune aberrations. Since the first order is suppressed by RF field, the second order plays crucial role. It depends on the orbit lengthening and on the odd order field components. We consider the spin decoherence effects and methods of their compensation in different channels, electrostatic, magnetostatic linking the decoherence effects with common characteristics such as the momentum compaction factor, the chromaticity and others.

WEPEA037	Testing of Symplectic Integrator of Spin-orbit Motion Based on Matrix Formalism	2582
	A.N. Ivanov, S.N. Andrianov, N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia R. Maier, Y. Senichev, D. Zyuzin FZJ, Jülich, Germany
	Investigation of spin-orbital motion in electromagnetic fields requires different numerical methods. Approaches for long-term evolution modelling need both performance and symplecticity. In this paper we discuss matrix maps method for numerical simulation. We examine symplectification and accuracy in terms of electostatic storage ring. The results are compared with traditional symplectic step-by-step methods.

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.

MOPEA017

Electron Cooling of Heavy Ions Interacting with Internal Target at HESR of FAIR

103

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

The High Energy Storage Ring (HESR) is designed and optimized to accumulate and store the anti-proton beam for the internal target experiment. The recent demand of atomic physics has impacted to use the HESR facility also as the storage ring of bare heavy ions. In this concept the bare heavy ions are injected at 740 MeV/u from the Collector Ring where the ions are well stochastically cooled to be matched with HESR ring acceptance. In the HESR the 2 MeV electron cooler is prepared with the maximal electron current of 3 A and the cooling length of 2.7 m. The electron cooling process of typically ²³⁸U⁹²⁺ beam is simulated for the Hydogen and Xe internal target with simultaneous use of barrier voltage to compensate the mean energy loss caused by the interaction with internal target. In the present report the detailed simulation results of 6D phase space obtained by the particle tracking code are precisely discussed.

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.

WEPEA036

Spin Tune Decoherence Effects in Electro- and Magnetostatic Structures

2579

Y. Senichev, R. Maier, D. Zyuzin
FZJ, Jülich, Germany
N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia

In Electric Dipole Moment search experiments with polarized beams the coherence of spin oscillations of particles has a crucial role. The decoherent effects arise due to spin tune dependence on particle energy and particle trajectory in focusing-deflecting fields. They are described through the n-th order spin tune aberrations. Since the first order is suppressed by RF field, the second order plays crucial role. It depends on the orbit lengthening and on the odd order field components. We consider the spin decoherence effects and methods of their compensation in different channels, electrostatic, magnetostatic linking the decoherence effects with common characteristics such as the momentum compaction factor, the chromaticity and others.

WEPEA037

Testing of Symplectic Integrator of Spin-orbit Motion Based on Matrix Formalism

2582

A.N. Ivanov, S.N. Andrianov, N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia
R. Maier, Y. Senichev, D. Zyuzin
FZJ, Jülich, Germany

Investigation of spin-orbital motion in electromagnetic fields requires different numerical methods. Approaches for long-term evolution modelling need both performance and symplecticity. In this paper we discuss matrix maps method for numerical simulation. We examine symplectification and accuracy in terms of electostatic storage ring. The results are compared with traditional symplectic step-by-step methods.