Download or read book Longitudinal Momentum Mining of Antiprotons at the Fermilab Recycler written by and published by . This book was released on 2007 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technique of longitudinal momentum mining (LMM)[1] in the Fermilab Recycler was adopted in early 2005 to extract thirty-six equal intensity and equal 6D-emittance antiproton bunches for proton-antiproton collider operation in the Tevatron. Since that time, several improvements have been made in the Recycler and the mining technique to handle higher intensity beams. Consequently, the Recycler has become a key contributor to the increased luminosity performance observed during Tevatron Run IIb. In this paper, we present an overview of the improvements and the current status of the momentum mining technique.
Download or read book Longitudinal Emittance Measurements in the Fermilab Recycler Ring written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Recycler Ring (RR) is a new 8Gev antiproton storage ring at Fermilab. Presently, this machine is being commissioned using protons from the Booster. It uses barrier buckets for stacking, un-stacking and storing the beam. At any given time, the RR is capable of storing proton or antiproton beams in multiple segments azimuthally. These segments of the beam may have widely differing longitudinal emittance and beam intensities and bunch lengths. It is highly essential to be able to measure the longitudinal emittance and keep track of the longitudinal dynamics at various stages of the operation of the RR. In this paper, the authors discuss a few methods of longitudinal emittance measurements in barrier buckets and discuss their merits and demerits.
Download or read book Antiproton Momentum Distributions as a Measure of Electron Cooling Force at the Fermilab Recycler written by S. Nagaitsev and published by . This book was released on 2006 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fermilab Recycler is a fixed 8 GeV kinetic energy storage ring located in the Fermilab Main Injector tunnel near the ceiling. Electron cooling of high energy antiprotons has recently been demosntrated [1] at the Recycler. Antiproton beam Schottky signals were used to measure the antiproton momentum distribution at equilibrium between a calibrated broadband diffusion source and electron cooling. The large Recycler momentum aperture, the dependence of the electron cooling force as a function of the antiproton momentum deviation and the calibrated diffusion source combine to give a unique sepectral measurement of the antiproton beam momentum distribution.
Download or read book Status of Antiproton Accumulation and Cooling at Fermilab s Recycler written by and published by . This book was released on 2009 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Recycler ring is an 8 GeV permanent magnet storage ring where antiprotons are accumulated and prepared for Fermilab's Tevatron Collider program. With the goal of maximizing the integrated luminosity delivered to the experiments, storing, cooling and extracting antiprotons with high efficiency has been pursued. Over the past two years, while the average accumulation rate doubled, the Recycler continued to operate at a constant level of performance thanks to changes made to the Recycler Electron Cooler (energy stability and regulation, electron beam optics), RF manipulations and operating procedures. In particular, we discuss the current accumulation cycle in which (almost equal to) 400 x 101° antiprotons are accumulated and extracted to the Tevatron every (almost equal to)15 hours.
Download or read book Antiproton Stacking and Un stacking in the Fermilab Recycler Ring written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fermilab Recycler Ring (RR) is intended to be used as a future antiproton storage ring for the Run II proton-antiproton collider operation. It is proposed that about 40mA of antiproton beam from the Accumulator Ring will be transferred to the Recycler once for every two to three hours, stacked and cooled. This operation continues for about 10 to 20 hours depending on the collider needs for antiprotons. Eventually, the cooled antiproton beam will be un-stacked from the Recycler and transferred to the Tevatron via the Main Injector. They have simulated stacking and un-stacking of antiprotons in the Recycler using multi-particle beam dynamics simulation code ESME. In this paper they present results of these simulations.
Download or read book Transverse Instabilities in the Fermilab Recycler written by and published by . This book was released on 2011 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transverse instabilities of the antiproton beam have been observed in the Recycler ring soon after its commissioning. After installation of transverse dampers, the threshold for the instability limit increased significantly but the instability is still found to limit the brightness of the antiprotons extracted from the Recycler for Tevatron shots. In this paper, we describe observations of the instabilities during the extraction process as well as during dedicated studies. The measured instability threshold phase density agrees with the prediction of the rigid beam model within a factor of 2. Also, we conclude that the instability threshold can be significantly lowered for a bunch contained in a narrow and shallow potential well due to effective exclusion of the longitudinal tails from Landau damping.
Download or read book Antiproton Cooling in the Fermilab Recycler Ring written by C. W. Schmidt and published by . This book was released on 2005 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 8.9-GeV/c Recycler antiproton storage ring is equipped with both stochastic and electron cooling systems. These cooling systems are designed to assist accumulation of antiprotons for the Tevatron collider operations. In this paper we report on an experimental demonstration of electron cooling of high-energy antiprotons. At the time of writing this report, the Recycler electron cooling system is routinely used in collider operations. It has helped to set recent peak luminosity records.
Download or read book The Fermilab Recycler Ring written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fermilab Recycler is a permanent magnet storage ring for the accumulation of antiprotons from the Antiproton Source, and the recovery and cooling of the antiprotons remaining at the end of a Tevatron store. It is an integral part of the Fermilab III luminosity upgrade. The following paper describes the design features, operational and commissioning status of the Recycler Ring.
Download or read book Fermilab Antiproton Source Recycler Ring and Main Injector written by and published by . This book was released on 2013 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observation of Longitudinal Diffusion and Cooling Due to Intra beam Scattering at the Fermilab Recycler Ring written by M. Hu and published by . This book was released on 2005 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fermilab Recycler Ring is a high-vacuum fixed energy antiproton storage ring with both stochastic (at present) and the future electron cooling systems. In this paper the technique for diffusion rate measurement, beam parameters and the analysis of data are presented, as well as the effect of intra-beam scattering on the operational considerations for the storage and cooling of the antiproton beam in the Recycler.
Download or read book Electron Cooling of 8 GeV Antiprotons at Fermilab s Recycler written by C. W. Schmidt and published by . This book was released on 2006 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron cooling of 8 GeV antiprotons at Fermilab's Recycler storage ring is now routinely used in the collider operation. It requires a 0.1-0.5 A, 4.3 MeV dc electron beam and is designed to increase the longitudinal phase-space density of the circulating antiproton beam. This paper briefly describes the characteristics of the electron beam that were achieved to successfully cool antiprotons. Then, results from various cooling force measurements along with comparison to a nonmagnetized model are presented. Finally, operational aspects of the implementation of electron cooling at the Recycler are discussed, such as adjustments to the cooling rate and the influence of the electron beam on the antiproton beam lifetime.
Download or read book Impedances and Beam Stability Issues of the Fermilab Recycler Ring written by and published by . This book was released on 1996 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fermilab Recycler Ring (permanent magnets) will be built on top of the Fermilab Main Injector sharing the same tunnel; its main function is to recycle the anti-protons after a store in the Tevatron and to provide storage for them after after accumulation and cooling in the Accumulator. Estimates of coupling impedances show domination by space charge. Examination of longitudinal instabilities shows that microwave instability will not occur if there are only N = 2.53 x 1012 anti-protons in the beam. Longitudinal coupling-bunch instability during injection stacking does not appear possible because of long bunch lengths/short bunch gaps and lack of sharp resonances. Transverse instability, on the other hand, cannot be Landau damped by the momentum spread in the beam, but it can be cured by a small spread in the betatron tunes (either from space charge or an octupole).
Download or read book Fermilab Recycler Stochastic Cooling Commissioning and Performance written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fermilab Recycler is a fixed 8 GeV kinetic energy storage ring located in the Fermilab Main Injector tunnel near the ceiling. The Recycler has two roles in Run II. First, to store antiprotons from the Fermilab Antiproton Accumulator so that the antiproton production rate is no longer compromised by large numbers of antiprotons stored in the Accumulator. Second, to receive antiprotons from the Fermilab Tevatron at the end of luminosity periods. To perform each of these roles, stochastic cooling in the Recycler is needed to preserve and cool antiprotons in preparation for transfer to the Tevatron. The commissioning and performance of the Recycler stochastic cooling systems will be reviewed.
Download or read book Antiproton Acceleration in the Fermilab Main Injector Using 2 5 MHz H written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: During the Run II era at Fermilab, the Recycler stores antiprotons at 8 GeV and the Main Injector accelerates the antiprotons and the protons from 8 GeV to 150 GeV for Tevatron injection. The Recycler injects antiprotons to the Main Injector in 2.5 MHz rf buckets. This report presents an acceleration scheme for the antiprotons that involves a slow ramp with initial 2.5 MHz acceleration and subsequent fast acceleration with 53 MHz rf system. Beam acceleration and rf manipulation with space charge and beam loading effects are simulated using the longitudinal simulation code ESME. Simulation suggests that one can expect about 15% emittance growth for the entire acceleration cycle with beam loading compensations. Preliminary experimental results with proton beam will also be presented.
Download or read book Transverse Instability of the Antiproton Beam in the Recycler Ring written by and published by . This book was released on 2011 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The brightness of the antiproton beam in Fermilab's 8 GeV Recycler ring is limited by a transverse instability. This instability has occurred during the extraction process to the Tevatron for large stacks of antiprotons even with dampers in operation. This paper describes observed features of the instability, introduces the threshold phase density to characterize the beam stability, and finds the results to be in agreement with a resistive wall instability model. Effective exclusion of the longitudinal tails from Landau damping by decreasing the depth of the RF potential well is observed to lower the threshold density by up to a factor of two.
Download or read book Survey and Alignment of the Fermilab Recycler Anti proton Storage Ring written by and published by . This book was released on 2000 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Survey and Alignment of the Fermilab Recycler Antiproton Storage Ring written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In June of 1999 Fermilab commissioned a newly constructed antiproton storage ring, the Recycler Ring, in the Main Injector tunnel directly above the Main Injector beamline. The Recycler Ring is a fixed 8 GeV kinetic energy storage ring and is constructed of strontium ferrite permanent magnets. The 3,319.4-meter-circumference Recycler Ring consists of 344 gradient magnets and 100 quadrupoles all of which are permanent magnets. This paper discusses the methods employed to survey and align these permanent magnets within the Recycler Ring with the specified accuracy. The Laser Tracker was the major instrument used for the final magnet alignment. The magnets were aligned along the Recycler Ring with a relative accuracy of "0.25.
