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[en] The results reached are now: momentum cooling at 609, 309 and 200 MeV/c, vertical cooling at 609 and 309 MeV/c, horizontal cooling at 609 and 309 MeV/c. Improvements planned in a near future, especially in the horizontal plane, are presented
[en] With the very successful commissioning of the vertical stochastic cooling in 100 GeV/n Au Run 2010, the IBS (intra-beam scattering) is no longer the dominant factor in terms of the integrated luminosity. A new luminosity model is needed, where the beam intensity lifetime is more important and the burn-off needs to be accounted for. Toward this goal, a brief review of the Run 2010, compared with Run 2007, is presented.
[en] The stringent alignment required for successful bunched beam stochastic cooling in FNAL's Tevatron necessitates the design and manufacture of a complex vacuum compatible mechanical alignment system. The design presented uses remote motion control to provide a positioning system with four degrees of freedom for placing two symmetric pickup loop arrays about the proton beam and with two degrees of freedom for aligning the arrays relative to each other. The system provides a 7.62 cm aperture between arrays during injection and a 1.90 cm aperture during operation while maintaining alignment between arrays within 50 μm. The system also allows precise remote longitudinal adjustment between pickup arrays with .002 μm resolution via a piezoelectric crystal inchworm motor in vacuum. Discussion includes the manufacture and installation of four complete pickup and kicker systems in the FNAL, Tevatron
[en] AN electrode array for stochastic cooling is being developed for use on the FNAL antiproton source. With minor power handling modifications, the same electrodes can function as pickups or as kickers. When used as pickups, a large array is needed to increase the signal-to-noise ratio. Each electrode is one element of a pair of directional coupler loops that are mounted flush with the upper and lower walls of the beam chamber. The loops, fabricated from flat metal plates, are supported by specially shaped legs
[en] The heart of all proposed Stochastic p accumulators is a ''fast'' momentum precooling section, whose performance must match the cycle time of the accelerators which supply and empty it of ps and/or the cooling time of a companion stacking section. Here some inherent design limitations of the fast cooling section and some ''ways out'', are discussed. 7 refs
[en] The primary devices for the stochastic cooling are: the sensor or Pick-Up, which detects the position of the particle to be corrected, the amplifier which amplifies the signal from the PU and feeds the Kicker, which is the reciprocal of the PU and corrects the particle position. This system could work instantaneously if the transfer function of the PU-amplifier-Kicker system were a delta function, namely, had an infinite bandwidth. In general the transfer function has a characteristic time, which is related to the bandwidth as follows: T=1/(2W). The bandwidth can be enlarged by reducing the cooling time. In this contribution a method is described to reach this, by increasing the central frequency of the PU (and the Kicker) making use of the Cherenkov radiation in the microwave range. (Auth.)
[en] 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 filters were removed from the debuncher stochastic cooling entirely.
[en] Major changes in the Stacktail Momentum Stochastic Cooling system have resulted in an improved stacking rate as well as the capability to stack larger quantities of antiprotons. Both these effects result in higher initial and integrated luminosity for colliding beam physics. An overview of the changes and actual system performance will be presented
[en] This paper is a very personal view of the field of geometric integration in accelerator physics-a field where often work of the highest quality is buried in lost technical notes or even not published; one has only to think of Simon van der Meer Nobel prize work on stochastic cooling-unpublished in any refereed journal. So I reconstructed the relevant history of geometrical integration in accelerator physics as much as I could by talking to collaborators and using my own understanding of the field. The reader should not be too surprised if this account is somewhere between history, science and perhaps even fiction