antiproton

Paper	Title	Other Keywords	Page
MOIO03	Current Plans for Beam Cooling at FAIR	ion, storage-ring, accumulation, secondary-beams	10
	M. Steck GSI, Darmstadt
	For the efficient production of secondary beams in the new FAIR accelerator complex beam cooling is a technique of outstanding importance. In the first stage of the FAIR project, the Modularized Start Version, stochastic cooling will be employed in the pre-cooling and accumulation of antiprotons. In a later stage the stochastic pre-cooling will also be applied to rare isotope beams. Further upgrades will be the installation of a dedicated antiproton accumulator ring and the use of electron cooling to provide ion beams, both stable ions and rare isotopes, for experiments with stored ions of highest phase space density. An overview of the current activities in beam cooling will be given.
	Slides
THIOA01	Ultimate Performance of Relativistic Electron Cooling at Fermilab	electron, ion, focusing, emittance	31
	A. V. Shemyakin, L. R. Prost Fermilab, Batavia
	The Fermilab’s Recycler ring employs a 4.3 MeV, 0.1 A DC electron beam to cool antiprotons for accumulation and preparation of bunches for the Tevatron collider. The most important features that distinguish the Recycler cooler from other existing electron coolers are its relativistic energy, a low value of the longitudinal magnetic field in the cooling section, ~100 G, and the lumped focusing in the electron beam lines. The report will summarize the experience of designing, commissioning, and optimizing the performance of this unique machine.
	Slides
TUIOB02	Simulations of Stochastic Cooling of Antiprotons in the Collector Ring CR	pick-up, kicker, betatron, emittance	58
	C. Dimopoulou, A. Dolinskii, T. Katayama, F. Nolden, C. Peschke, M. Steck GSI, Darmstadt D. Möhl, L. Thorndahl CERN, Geneva
	The Collector Ring at FAIR will be equipped with pertinent stochastic cooling systems in order to achieve fast cooling of the hot secondary beams, antiprotons and rare isotopes, thus profiting from the repetition rate of the SIS100 synchrotron. Detailed simulations of the system performance are needed for optimization as well as input for the users of the CR pre-coooled beams, e.g. HESR. We presently focus on the antiproton cooling in the band 1-2 GHz. After a short overview, results from Fokker-Planck simulations with the CERN code of the momentum cooling of antiprotons will be presented. The performance of the betatron cooling of antiprotons, which has to proceed simultaneously with the momentum cooling, was calculated separately by means of an analytical model. First results and their implications will be discussed, including an outlook to future simulation work.
	Slides
WECOB01	Methods for Optimization of the Dynamics of the Storage of Positrons in the Surko Trap	positron, accumulation, plasma, electron	81
	M. K. Eseev, A. G. Kobets, I. N. Meshkov, A. Yu. Rudakov, S. Yakovenko JINR, Dubna, Moscow Region
	Surko traps are used successfully, example, for the accumulation of positrons and antiprotons in the experiments on the generation of antihydrogen atoms the ALPHA/CERN. The report presents methods for optimizing the dynamics of the storage of positrons in the Surko trap based on experimental studies on the trap the facility LEPTA/JINR and theoretical estimates of the accumulation and dynamics of particles with technique "Rotating Wall".
	Slides
WEIOA01	Enhancing Trappable Antiproton Populations Through an Induction Unit Followed by Frictional Cooling	rfq, scattering, simulation, induction	85
	A. Sessler, G. Penn, J. S. Wurtele, M. S. Zolotorev LBNL, Berkeley, California A. E. Charman UCB, Berkeley, California
	An induction unit, followed by frictional cooling, is applied to the antiproton bunches delivered by CERN's antiproton decelerator (AD) at 5 MeV. The scheme requires about 1 meter of induction unit to reduce a fraction of the 200 ns pulse to 60 keV after which frictional cooling, involving a set of thin foils, reduces the anti-protons to about 5 keV where they can be captured in an anti-proton trap. The scheme is compared to a further de-acceleration ring (such as ELENA) and to a degrading foil from the 5 MeV of the AD alone. Theory and simulations provide a preliminary assessment of the concept's strengths and limitations. The comparisons are limited largely by poorly-known levels of multiple scattering of low-energy antiprotons and experimental experience is employed.
	Slides
WECOA01	Ion Kinetics in the Ultra-low Energy Electrostatic Storage Ring (USR)	ion, target, electron, storage-ring	89
	A. I. Papash MPI-K, Heidelberg A. V. Smirnov JINR, Dubna, Moscow Region C. P. Welsch The University of Liverpool, Liverpool
	The Ultra-low energy Storage Ring (USR) at the Facility for Low-energy Antiproton and Ion Research (FLAIR) will provide cooled beams of antiprotons in the energy range between 300 keV down to 20 keV and possibly less. A large variety of the envisaged experiments including in-ring collision experiments with a reaction microscope require a comprehensive study of the long term beam dynamics processes in the ring. Detailed investigations into the ion kinetics under consideration of the effects from electron cooling and multiple scattering of the beam on a supersonic gas jet target have been carried out using the BETACOOL code. The life time, equilibrium momentum spread and equilibrium lateral spread during collisions with this internal gas jet target were estimated. The results from simulations were benchmarked against experimental data of beam losses in the ELISA storage ring. In addition, the results from experiments at the TSR ring where a 93 keV/u beam CF+ ions has been shrunk to extremely small dimensions have been reproduced. Based on these simulations, conditions for stable ring operation with extremely low emittance beam are presented. Finally, results from studies into the interaction of ions with a gas jet target at very low energies are summarized.
	Slides
TUPS20	Demonstration of Longitudinal Stacking in the ESR with Barrier Buckets and Stochastic Cooling	injection, kicker, accumulation, synchrotron	140
	M. Steck, C. Dimopoulou, B. Franzke, O. E. Gorda, T. Katayama, F. Nolden, G. Schreiber GSI, Darmstadt I. N. Meshkov, A. O. Sidorin, G. V. Trubnikov JINR, Dubna, Moscow Region D. Möhl CERN, Geneva R. Stassen, H. Stockhorst FZJ, Jülich
	Fast longitudinal beam accumulation has been demonstrated in the ESR at GSI with an Ar18+ beam coming from the synchrotron SIS18 at 400 MeV/u. Continuous application of stochastic cooling in all three phase space directions, merges the stack with the new injected bunch. Longitudinal beam compression was achieved by using either short barrier bucket rf pulses or by successive injections onto the unstable fixed point of the rf bucket at h=1. This recent experiment in the ESR provides the proof of principle for the planned longitudinal stacking of pre-cooled antiprotons in the HESR, injected from the CR.