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Stochastic Cooling for Bunched Beams.

Description: Problems associated with bunched beam stochastic cooling are reviewed. A longitudinal stochastic cooling system for RHIC is under construction and has been partially commissioned. The state of the system and future plans are discussed.
Date: May 16, 2005
Creator: Blaskiewicz, M.
Partner: UNT Libraries Government Documents Department
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Stochastic cooling overview

Description: The status of stochastic cooling and developments over the years are reviewed with reference to much of the original work. Both theoretical and technological subjects are considered.
Date: July 1, 2003
Creator: Marriner, John P
Partner: UNT Libraries Government Documents Department
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Antiproton stacking in the Recycler

Description: Possibilities to accumulate antiprotons in the Recycler are considered for three different cases: with current stochastic cooling, with upgraded stochastic cooling and with electron cooling. With stochastic cooling only, even upgraded, Recycler looks hardly useful. However, with electron cooling at its goal parameters and reasonably good vacuum in the Recycler, this machine would be efficient.
Date: June 23, 2003
Creator: Burov, Alexey
Partner: UNT Libraries Government Documents Department
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Stochastic Cooling of High-Energy Bunched Beams

Description: Stochastic cooling of 100 GeV/nucleon bunched beams has been achieved in the Relativistic Heavy Ion Collider (RHIC). The physics and technology of the longitudinal cooling system are discussed, and plans for a transverse cooling system are outlined.
Date: June 25, 2007
Creator: Blaskiewicz, M. & Brennan, J. M.
Partner: UNT Libraries Government Documents Department
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Observation of the Coalescing of Beam Into an Asymmetric RF Bucket by Stochastic Cooling

Description: Antiprotons in the debuncher ring at Fermilab have been observed to be bunched outside of the 'barrier bucket' when cooled to small {Delta}p/p with the stochastic cooling. This bunching occurs in the same location as a very small stable bucket in the RF wave form. The stochastic cooling appears to be causing beam that is originally uniformly distributed to be captured by this stable bucket.
Date: January 1, 1993
Creator: Halling, Alfred Mike & Lu, Xian Ping
Partner: UNT Libraries Government Documents Department
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STOCHASTIC COOLING POWER REQUIREMENTS.

Description: A practical obstacle for stochastic cooling in high-energy colliders like RHIC is the large amount of power needed for the cooling system. Based on the coasting-beam Fokker-Planck (F-P) equation, we analytically derived the optimum cooling rate and cooling power for a beam of uniform distribution and a cooling system of linear gain function. The results indicate that the usual back-of-envelope formula over-estimated the cooling power by a factor of the mixing factor M. On the other hand, the sc… more
Date: July 5, 2004
Creator: Wei, J.; Blaskiewicz, M. & Brennan, M.
Partner: UNT Libraries Government Documents Department
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Stochastic cooling in RHIC

Description: After the success of longitudinal stochastic cooling of bunched heavy ion beam in RHIC, transverse stochastic cooling in the vertical plane of Yellow ring was installed and is being commissioned with proton beam. This report presents the status of the effort and gives an estimate, based on simulation, of the RHIC luminosity with stochastic cooling in all planes.
Date: May 4, 2009
Creator: Brennan,J. M.; Blaskiewicz, M. M. & Severino, F.
Partner: UNT Libraries Government Documents Department
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A Split-Function Lattice for Stochastic Cooling

Description: Lattice for a 3-GeV cooler ring with split functions is presented. The ring consists of two half-rings of different properties: in one half-ring, the phase-slip factor is near-zero; in the other half-ring, the phase-slip factor is large. The near-zero phase slip minimizes the 'bad mixing' between the stochastic-cooling pick-ups and kickers, while the high phase slip maximizes the 'good mixing' between the kickers and the next-turn pick-ups.
Date: September 10, 2007
Creator: Wei, J.
Partner: UNT Libraries Government Documents Department
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Design of Microwave Band Pass Filters for the Debuncher Stochastic Cooling System

Description: The FIR filters designed for the debuncher stochastic cooling system needed improvement. Its bandwidth was too wide, its magnitude was not flat, its phase ripple was too great, and it was difficult to control the characteristics of the filter. A simple microwave technique was employed to have a short time delay, simple robust layout, and small board size. A significant savings was seen over the FIR technique and these filters were installed in the Antiproton Source Debuncher while the FIR filte… more
Date: January 1, 2001
Creator: Deibele, C.
Partner: UNT Libraries Government Documents Department
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Bunched beam stochastic cooling in the Fermilab Recycler Ring

Description: Stochastic cooling with bunched beam in a linear bucket has been obtained and implemented operationally in the Fermilab Recycler Ring (RR). This is the first time that linear-rf bunched-beam stochastic cooling has been successfully used operationally in a high-energy facility. In this implementation the particle bunch length is much greater than the cooling system wavelengths, and that property is critical to the cooling success. The simultaneous longitudinal bunching enables cooling to much sm… more
Date: May 1, 2005
Creator: Broemmelsiek, D.; Burov, A.; Nagaitsev, S.; Neuffer, D. & /Fermilab
Partner: UNT Libraries Government Documents Department
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A discussion of bunched beam stochastic cooling

Description: The analysis of Herr and Mohl[1] is used as a basis for a discussion of bunched beam cooling in the Fermilab recycler and the Tevatron. Differences between the two cooling regimes are discussed. Criteria discussed in that paper imply the failure of stochastic cooling in the Tevatron while permitting the success of stochastic cooling in the Recycler. These ''predictions'' are in agreement with observations.
Date: August 1, 2005
Creator: Neuffer, David
Partner: UNT Libraries Government Documents Department
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Analysis of optical stochastic cooling including transverse effects

Description: The phase space area plays an important role in determining the performance of optical stochastic cooling. Specifically, the number of samples in the beam consists of three factors corresponding to three dimensions, the factor in each dimension being given by the ratio of the total phase space area in that dimension to the radiation wavelength.
Date: May 1, 1995
Creator: Kim, K. J. & Zege, A. V.
Partner: UNT Libraries Government Documents Department
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Vacuum Consideration Pertaining to Bellows Changes on Debuncher Tanks

Description: It has been proposed that the stochastic cooling tanks in the Debuncher be modified so that their position can be changed remotely by installing motor driven stands. The present bellows that connect the tanks to the beam pipe vacuum chamber does not have enough radial movement to allow the movement required of the tanks. In order for this proposal to be enacted, the existing bellows will have to be replaced. The present bellows is a formed bellows 5 1/2-inch I.D. x 2-inch long, it will be repla… more
Date: November 13, 1985
Creator: Klen, J.
Partner: UNT Libraries Government Documents Department
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Radio Frequency Notch Filter Utilizing Fiber Optic Laser Diode Delay Line

Description: A wide band, laser-diode/fiber-optic transmission line (FOL) has been developed which represents a potentially useful stochastic cooling notch filter element. Because of its small size and lack of need for sophisticated support equipment the FOL presents a viable alternative to both conventional and super conducting coaxial line notch filters. This note summarizes the characteristics of the FOL and of notch filter performance achieved with its use.
Date: April 1, 1985
Creator: Konecny, R.
Partner: UNT Libraries Government Documents Department
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Simple Lattice for the Precoo1er/Accumu1ator Scheme

Description: The Precoo1er/Accumu1ator scheme uses RF stacking to collect antiprotons produced by a mu1tipu1se proton extraction from the Main Ring. The stacking requires X{sub p} {approx} 2.5 m at the injection septum; therefore, a simple expansion of the present precoo1er lattice from {bar R} = 75 m to {bar R} = 101 m is not practical. It is possible that an appropriate high-X{sub p} insertion could be designed so that the increase in {gamma}{sub T} from the larger ring would cancel the decrease caused by… more
Date: October 23, 1980
Creator: MacLachlan, James
Partner: UNT Libraries Government Documents Department
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Synchrotron frequency spread independence of bunched-beam stochastic cooling at the Fermilab Recycler

Description: It is generally accepted that longitudinal stochastic cooling of bunched beams is not possible without a synchrotron frequency spread. Experiments in the Recycler storage ring (Fermilab) demonstrate the opposite: with an antiproton bunch in a parabolic potential well (no synchrotron frequency spread), the cooling was almost as efficient as in a trapezoidal potential well (with a relative synchrotron frequency spread of {approx} 100%). A possible explanation is that, at Recycler parameters, diff… more
Date: November 1, 2005
Creator: Broemmelsiek, D.; Burov, Alexey V.; Nagaitsev, S. & Neuffer, D.
Partner: UNT Libraries Government Documents Department
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Bunched Beam Stochastic Cooling Simulaitons and Comparison With Data

Description: With the experimental success of longitudinal, bunched beam stochastic cooling in RHIC it is natural to ask whether the system works as well as it might and whether upgrades or new systems are warranted. A computer code, very similar to those used for multi-particle coherent instability simulations, has been written and is being used to address these questions.
Date: September 10, 2007
Creator: Blaskiewicz, M. & Brennan, J. M.
Partner: UNT Libraries Government Documents Department
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Performance and upgrades of the Fermilab Accumulator stacktail stochastic cooling

Description: We report on the performance and planned upgrades to the Fermilab Accumulator Stacktail Stochastic Cooling System. The current system has achieved a maximum flux of 16.5e10/hour, limited by the input flux of antiprotons. The upgrades are designed to handle flux in excess of 40e10/hour.
Date: November 1, 2005
Creator: Derwent, P. F.; Cullerton, Ed; McGinnis, David; Pasquinelli, Ralph; Sun, Ding & Tinsley, David
Partner: UNT Libraries Government Documents Department
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Cooling in a compound bucket

Description: Electron cooling in the Fermilab Recycler ring is found to create correlation between longitudinal and transverse tails of the antiproton distribution. By separating the core of the beam from the tail and cooling the tail using 'gated' stochastic cooling while applying electron cooling on the entire beam, one may be able to significantly increase the overall cooling rate. In this paper, we describe the procedure and first experimental results.
Date: September 1, 2007
Creator: Shemyakin, A.; Bhat, C.; Broemmelsiek, D.; Burov, A.; Hu, M. & /Fermilab
Partner: UNT Libraries Government Documents Department
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STOCHASTIC COOLING STUDIES IN RHIC, II.

Description: Intra-beam scattering (IBS) is unavoidable for highly charged heavy ions and causes emittance growth during the store for collision physics. A longitudinal bunched beam stochastic cooling system will confine the bunch within the RF bucket increasing the useful luminosity. We describe a series of measurements in RHIC that have been used to verify our understanding of the relevant physics and the cooling system architecture that is being prototyped.
Date: July 5, 2004
Creator: BLASKIEWICZ,M. BRENNAN,J. M. WEI,J.
Partner: UNT Libraries Government Documents Department
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Bunched Beam Stochastic Cooling Project for RHIC.

Description: The main performance limitation for RHIC is emittance growth caused by IntraBeam Scattering during the store. We have developed a longitudinal bunched-beam stochastic cooling system in the 5-8 GHz band which will be used to counteract IBS longitudinal emittance growth and prevent de-bunching during the store. Solutions to the technical problems of achieving sufficient kicker voltage and overcoming the electronic saturation effects caused by coherent components within the Schottky spectrum are d… more
Date: September 18, 2005
Creator: Brennan, J. M. & Baskiewicz, M. M.
Partner: UNT Libraries Government Documents Department
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