COOL 2007 - List of Keywords (proton)

A B C D E F G H I K L O P Q R S T U V

proton

Paper	Title	Other Keywords	Page
MOA1I01	Bunched Beam Stochastic Cooling at RHIC	kicker, ion, pick-up, beam-losses	25
	J. M. Brennan, M. Blaskiewicz BNL, Upton, Long Island, New York
	Stochastic cooling of ions in RHIC has been implemtneted to counteract Intra-Beam Scattering and prevent debunching during stores for luminosity production. The two main challenges in cooling bunched beam at 100 GeV/n are the coherent components in the Schottky spectra and producing the high voltage for the kicker in the 5 - 8 GHz band required for optimal cooling. The technical solutions to these challenges are described. Results of cooling proton beam in a test run and cooling gold ions in the FY07 production run are presented.
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MOA1C02	Stochastic Cooling for the HESR at FAIR	target, antiproton, emittance, pick-up	30
	H. Stockhorst, R. Maier, D. Prasuhn, R. Stassen FZJ, Jülich T. Katayama CNS, Saitama L. Thorndahl CERN, Geneva
	The High-Energy Storage Ring (HESR) of the future International Facility for Antiproton and Ion Research (FAIR) at the GSI in Darmstadt is planned as an anti-proton cooler ring in the momentum range from 1.5 to 15 GeV/c. An important and challenging feature of the new facility is the combination of phase space cooled beams with internal targets. The required beam parameters and intensities are prepared in two operation modes: the high luminosity mode with beam intensities up to 10¹¹ and the high resolution mode with 10¹⁰ anti-protons cooled down to a relative momentum spread of only a few 10^-5. In addition to electron cooling transverse and longitudinal stochastic cooling are envisaged to accomplish these goals. A detailed numerical and analytical approach to the Fokker- Planck equation for momentum cooling including an internal target has been carried out to demonstrate the stochastic cooling capability. Cooling model predictions are compared with the stochastic cooling performance of the operational cooling system in the cooler synchrotron COSY.
	Slides

TUM2I06	Cooling Scheme for a Muon Collider	collider, simulation, lattice, emittance	77
	R. B. Palmer, J. S. Berg, R. C. Fernow, J. C. Gallardo, H. G. Kirk BNL, Upton, Long Island, New York Y. Alexahin, D. V. Neuffer Fermilab, Batavia, Illinois S. A. Kahn Muons, Inc, Batavia D. J. Summers UMiss, University, Mississippi
	Abstract text to be submitted by the author
	Slides

TUA1C03	Necessary Condition for Beam Ordering	electron, ion, scattering, simulation	87
	A. V. Smirnov, I. N. Meshkov, A. O. Sidorin JINR, Dubna, Moscow Region J. Dietrich FZJ, Jülich A. Noda, T. Shirai, H. Souda, H. Tongu Kyoto ICR, Uji, Kyoto K. Noda NIRS, Chiba-shi
	The very low momentum spread for small number of particle was reached on different storage rings. When the sudden reduction of the momentum spread ("phase transition") was observed during decreasing of the particle number it was interpreted as ordered state of ion beams. The most extensive study of ordered ion beams was done on storage rings ESR (GSI, Darmstadt) and CRYRING (MSL, Stockholm). Recently, for the first time, the ordered proton beam has been observed on S-LSR (Kyoto University). From analysis of the ESR experimental results we assumed that the ordered state can be observed if the dependence of momentum spread on the particle number can be approximated as ∆P/P ~ N^k for k < 0.3. In pioneering experiments at NAP-M (INP, Novosibirsk) and, in recent years, at COSY (FZJ, Juelich) the phase transition was not observed and the coefficient was found equal k > 0.5. This report presents the experimental investigations of low intensity proton beams on COSY and S-LSR which have the aim to formulate the necessary conditions for the achievement of the ordered state. The experimental studies on S-LSR and numerical simulations with the BETACOOL code were done for the dependence of the momentum spread and transverse emittances on particle number with different misalignments of the magnetic field at the cooler section. As result of both experimental and numerical studies one can conclude that the necessary condition for the phase transition appearance is k < 0.3.
	Slides

TUA2C06	A Split-Function Lattice for Stochastic Cooling	lattice, pick-up, kicker, dipole	99
	J. Wei BNL, Upton, Long Island, New York S. Wang IHEP Beijing, Beijing
	*Funding: Work performed under the auspices of the US Department of Energy.** During the EPAC 2006 we reported the lattice design for rapid-cycling synchrotrons used to accelerate high-intensity proton beams to energy of tens of GeV for secondary beam production. After primary beam collision with a target, the secondary beam can be collected, cooled, accelerated or decelerated by ancillary synchrotrons for various applications. For the main synchrotron, the lattice has: flexible momentum compaction to avoid transition and to facilitate RF gymnastics long straight sections for low-loss injection, extraction, and high-efficiency collimation dispersion-free straights to avoid longitudinal-transverse coupling, and momentum cleaning at locations of large dispersion with missing dipoles. Then, we present a lattice for a cooler ring for the secondary beam. The momentum compaction across half of this ring is near zero, while for the other half it is normal. Thus, bad mixing is minimized while good mixing is maintained for stochastic beam cooling.
	Slides

THM1I02	Electron Cooling Experiments at S-LSR	electron, ion, heavy-ion, simulation	139
	T. Shirai, S. Fujimoto, M. Ikegami, A. Noda, H. Souda, M. Tanabe, H. Tongu Kyoto ICR, Uji, Kyoto H. Fadil, M. Grieser MPI-K, Heidelberg T. Fujimoto, S. I. Iwata, S. Shibuya AEC, Chiba I. N. Meshkov, A. V. Smirnov, E. Syresin JINR, Dubna, Moscow Region K. Noda NIRS, Chiba-shi
	Funding: The present work has been supported from Advanced Compact Accelerator Development Project by MEXT of Japan and 21 COE at Kyoto University-Center for Diversity and Universality in Physics. The ion storage ring, S-LSR in Kyoto University has an electron beam cooler and a laser cooling system. The electron cooler for S-LSR was designed to maximize the cooling length in the limited drift space of the ring. The effective cooling length is 0.44 m, while the total length of the cooler is 1.8 m. The commissioning of the electron cooling was started from October 2005. The 7 MeV proton beam from the linac was used and the first cooling was observed on October 31. The momentum spread became 2×10^-4 and the beam diameter was 1.2 mm with the particle number of 2×10⁸ and the electron current of 60 mA. The various experiments have been carried out using the electron cooling at S-LSR. The one-dimensional ordering of protons is one of the important subjects. The momentum spread and the beam size were observed while reducing the particle number. They were measured by the Schottky noise spectrum and the scraper. The particle number was measured by the ionization residual gas monitor. Abrupt jumps in the momentum spread and the Schottky noise power were observed for protons at a particle number of around 2000. The beam temperature was 0.17 meV and 1 meV in the longitudinal and transverse directions at the transition particle number, respectively. The normalized transition temperature of protons is close to those of heavy ions at ESR. The lowest momentum spread below the transition was 1.4×10^-6, which corresponded to the longitudinal beam temperature of 0.026 meV (0.3 K). It is close to the longitudinal electron temperature. The transverse temperature of the proton beam was much below that of electrons (34 meV). It is the effect of the magnetized electron.

THM2I04	Progress with Tevatron Electron Lenses	electron, antiproton, gun, simulation	144
	V. Kamerdzhiev, Y. Alexahin, G. F. Kuznetsov, V. D. Shiltsev, X. Zhang Fermilab, Batavia, Illinois
	Funding: Work supported by the U. S. Department of Energy under contract No. DE-AC02-07CH11359 The Tevatron Electron Lenses (TELs) were initially proposed for compensation of long-range and head-on beam-beam effects of the antiproton beam at 980 GeV. Recent advances in antiproton production and electron cooling led to a significant increase of antiproton beam brightness. It is now the proton beam that suffers most from the beam-beam effects. Discussed are the concept of Electron Lenses and commissioning of the second TEL in 2006-2007. The latest experimental results obtained during numerous studies with high energy proton beam are presented.
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THAP22	Limitations of the Observation of Beam Ordering	ion, electron, scattering, emittance	217
	M. Steck, K. Beckert, P. Beller, C. Dimopoulou, F. Nolden GSI, Darmstadt
	One dimensional beam ordering of electron cooled low intensity heavy ion beams has been evidenced at the ESR storage ring as a discontinuous reduction of the momentum spread. Depending on the beam parameters, technical imperfections or any sources of heating can hamper or even prevent the observation of the momentum spread reduction. Limitations for the detection of the ordered beam will be described and illustrated by experimental results.

FRM1I01	Present Status and Recent Activity on Laser Cooling at S-LSR	laser, ion, induction, storage-ring	221
	A. Noda, M. Ikegami, T. Ishikawa, M. Nakao, T. Shirai, H. Souda, M. Tanabe, H. Tongu Kyoto ICR, Uji, Kyoto M. Grieser MPI-K, Heidelberg I. N. Meshkov, A. V. Smirnov JINR, Dubna, Moscow Region K. Noda NIRS, Chiba-shi
	Funding: The present work has been supported from Advanced Compact Accelerator Development Project by MEXT of Japan and 21 COE at Kyoto University-Center for Diversity and Universality in Physics. Ion storage and cooler ring, S-LSR, has been designed to enable the investigation of coldest possible ion beams with use of various beam cooling schemes such as an electron beam cooling and the laser cooling. Electron beam cooling of 7 MeV protons and laser cooling of 40 keV Mg ions have been applied up to now.　The first laser cooling applied to ~10⁸ Mg ions with the induction accelerator voltage of ~6 mV reduced the momentum spread (1 σ) from 1.7×10^-3 to 2.9×10^-4, which is considered to be saturated by the momentum transfer from transverse degree of freedom to the longitudinal one due to intra-beam scattering. The laser cooling force has been improved from the above one more than one order of magnitude owing to the precise alignment between the laser and Mg ion beam. Recent measurement with frequency shift of the laser showed the enhancement of the coherent signals in odd harmonics of the revolution frequency picked up with an electrostatic beam monitor and detailed measurements of various harmonics have been performed with changing the resolution bandwidth of the spectrum analyzer, although the origin of such coherency is not yet identified up to now. For the purpose of measurement of lowest possible temperature attainable by the laser cooling, measurement with reducing the ion numbers of Mg is needed, which has been blocked by the difficulty of observing the Schotty signal of such a low intensity beam. So as to cope with this situation, development of observing system of emitted light by the transition from the upper level to the ground state with the use of photomultiplier has been performed, which recently succeeded in detection of clear signals coming from the oriented process. Activities above mentioned will be presented together with the forth coming experimental results on laser cooling.
	Slides

FRM2C04	Studies of Cooling and Deceleration at CRYRING for FLAIR	ion, antiproton, electron, space-charge	234
	H. Danared, A. Källberg, A. Simonsson MSL, Stockholm
	It is planned that the CRYRING synchrotron and storage ring will be moved to the future FAIR facility at GSI. There it will be used as the Low-energy Storage Ring LSR at FLAIR (Facility for Low-energy Antiproton and Ion Research). LSR will mainly be used for deceleration of antiprotons from 30 MeV down to minimum 300 keV and for deceleration of highly charged ions in the same range of magnetic rigidities. As a preparation for the transfer of CRYRING to FAIR, studies have been made in order to evaluate the performance of CRYRING for deceleration of particles relevant to FLAIR and to set specifications for beams in and out of LSR. Deceleration of protons have been studied by first accelerating the particles to 30 MeV, then decelerating back to 300 keV again. Up to 3·10⁸ protons have been decelerated in 1.8 s without intermediate cooling, and requirements on longitudinal and transverse emittances at 30 MeV for successful deceleration have been estimated. Other studies have included investigations of the space-charge limit for protons at 300 keV and measurements of transverse cooling times for H^- ions, simulating antiprotons. Also an attempt to compare longitudinal cooling forces between protons and H^- ions has been made.
	Slides