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20 TeV collider lattices with low-. beta. insertions

Description: A lattice containing insertions designed for collisions of 20 TeV proton beams at crossing points having beta values of two meters or less is presented. The machine would use high-field double bore superconducting magnets, with opposite focusing action on the two beams passing through each quadrupole. Hence the focusing pattern in the insertions is antisymmetric about the crossings. The beams, separated by 16 cms in the arcs are made colinear by dipoles common to both beams and then focused to the low-..beta.. collision points by quadrupole triplets. A similar machine design for pp collisions is also included.
Date: August 1, 1983
Creator: Garren, A.A.
Partner: UNT Libraries Government Documents Department

Summary of the working group on high current transport and final focus lenses

Description: The group reviewed recent work, and then addressed itself to relating the current understanding of relevant beam transport effects to the four reference concepts. In addition there was discussion on plans for future experimental and theoretical work. Discussions covered the following topics: (1) Transverse instabilities on intense beams through periodic focusing systems, (2) evaluation and correction of chromatic aberrations in the final beam transport lines, (3) evaluation and correction of geometric aberrations due to quadrupole fringe fields, and (4) ion focusing by electrons.
Date: September 1, 1978
Creator: Garren, A.A.
Partner: UNT Libraries Government Documents Department

6. 5 Tesla SSC lattice example

Description: This note presents an example SSC collider lattice for 20 TeV proton beams using 6.5 Tesla double bore magnets, six collision points, and anti-symmetric insertions.
Date: January 1, 1984
Creator: Garren, A.A.
Partner: UNT Libraries Government Documents Department

Lattice and bypass design for a coherent xuv facility

Description: The design of a magnet lattice and bypass for a coherent radiation facility is discussed. The lattice is the missing magnet FODO structure first proposed by Vignola for a 6 GeV light source. This has been adapted for a 750-1300 MeV electron storage ring for use with both conventional insertion devices and a high gain FEL optimized for output at 400 A. The latter device requires that the electron bunch be deflected into a small aperture bypass, then reinjected into the ring where the perturbing effects of the FEL are damped out. 8 refs., 7 figs.
Date: May 1, 1985
Creator: Jackson, A.; Garren, A.A. & Vignola, G.
Partner: UNT Libraries Government Documents Department

Chromatic properties and tracking studies of a 20 TeV pp collider

Description: The chromatic properties of a lattice for the 20 TeV pp collider described in an accompanying paper have been investigated. Since this machine has a low ..beta..-function value at the interaction points (..beta../sub x,y/ = 2 m), the large value in the nearby quadrupoles is a major source of perturbations for off-momentum particles. Preliminary tracking studies have been performed in an attempt to determine the dynamic aperture. The model includes the effects of chromaticity sextupoles, octupoles to straighten the working line, random multipoles simulating magnet construction errors and closed orbit distortions.
Date: August 1, 1983
Creator: Garren, A.; Cornacchia, M. & Dell, F.
Partner: UNT Libraries Government Documents Department

Focusing of heavy-ion beams on a fusion target

Description: A beam line has been designed for transport between a periodic channel and a fusion target in a way intended to minimize effects of non-uniform transverse and longitudinal densities and of momentum spread. Principles used for the design are explained. The beam line is described and its performance as shown by envelope integration and particle simulation is presented.
Date: March 1, 1981
Creator: Garren, A.; Krafft, G. & Haber, I.
Partner: UNT Libraries Government Documents Department

Beam separation for p-anti p collisions in a single ring in the multibunch mode

Description: A discussion is given of proton-antiproton colliding beam operation in storage rings. Some means of separating the beams at points where no experiment is being performed seems to be an important feature for a p-anti p colliding beam ring. By exciting a betatron oscillation in some appropriate, localized region, one could create a specific collision point while at the same time cause the p and anti p beams to oscillate in opposition so that their orbits meet at only a small number of points, roughly given by twice the tune, 2..nu...
Date: January 1, 1978
Creator: Berley, D.; Garren, A.A. & Month, M.
Partner: UNT Libraries Government Documents Department

Advanced medical accelerator design

Description: This report describes the design of an advanced medical facility dedicated to charged particle radiotherapy and other biomedical applications of relativistic heavy ions. Project status is reviewed and some technical aspects discussed. Clinical standards of reliability are regarded as essential features of this facility. Particular emphasis is therefore placed on the control system and on the use of technology which will maximize operational efficiency. The accelerator will produce a variety of heavy ion beams from helium to argon with intensities sufficient to provide delivered dose rates of several hundred rad/minute over large, uniform fields. The technical components consist of a linac injector with multiple PIG ion sources, a synchrotron and a versatile beam delivery system. An overview is given of both design philosophy and selected accelerator subsystems. Finally, a plan of the facility is described.
Date: November 1, 1982
Creator: Alonso, J.R.; Elioff, T. & Garren, A.
Partner: UNT Libraries Government Documents Department

Design of the muon collider lattice: Present status

Description: The last component of a muon collider facility, as presently envisioned, is a colliding-beam storage ring. Design studies on various problems for this ring have been in progress over the past year. In this paper we discuss the current status of the design. The projected muon currents require very low beta values at the IP, {beta}* = 3 mm, in order to achieve the design luminosity of L = 10{sup 35} cm{sup -2} s{sup -1}. The beta values in the final-focus quadrupoles are roughly 400 km. To cancel the corresponding chromaticities, sextupole schemes for local correction have been included in the optics of the experimental insertion. The hour-glass effect constraints the bunch length to be comparable too. To obtain such short bunches with reasonable rf voltage requires a very small value of the momentum compaction a, which can be obtained by using flexible momentum compaction (FMC) modules in the arcs. A preliminary design of a complete collider ring has now been made; it uses an experimental insertion and arc modules as well as a utility insertion. The layout of this ring is shown schematically, and its parameters are summarized. Though some engineering features are unrealistic, and the beam performance needs some improvement, we believe that this study can serve as the basis for a workable collider design. The remaining sections of the paper will describe the lattice, show beam behaviour, and discuss future design studies.
Date: May 1996
Creator: Garren, A.; Courant, E. & Gallardo, J.
Partner: UNT Libraries Government Documents Department

Optimization of superconducting bending magnets for a 1.0 to 1.5 GeV compact light source

Description: Compact light sources are being proposed for protein crystallography, medical imaging, nano-machining and other areas of study that require intense sources of x rays at energies up to 35 keV. In order for a synchrotron light source to be attractive, its capital cost must, be kept low. The proposed compact light source has superconducting bending elements to bend the stored beam and produce the x rays. Additional focusing for the machine is provided by conventional quadrupoles. An important part of the cost optimization of a compact light source is the cost of the bending magnets. In the case of a machine with superconducting bending elements, the bending magnet system can represent close to half of the storage ring cost. The compact light source storage rings studied here have a range of stored electron energies from 1.0 to 1.5 GeV. For a number of reasons, it is desirable to keep the storage ring circumference below 30 meters. Cost optimization parameters include: (1) the number of superconducting bending elements in the ring, and (2) the central induction of the dipole. A machine design that features two superconducting dipoles in a single cryostat vacuum vessel is also discussed.
Date: June 1, 1995
Creator: Green, M.A. & Garren, A.A.
Partner: UNT Libraries Government Documents Department

Feasibility Study of Compact Gas-Filled Storage Ring for 6D Cooling of Muon Beams

Description: The future of elementary particle physics in the USA depends in part on the development of new machines such as the International Linear Collider, Muon Collider and Neutrino Factories which can produce particle beams of higher energy, intensity, or particle type than now exists. These beams will enable the continued exploration of the world of elementary particles and interactions. In addition, the associated development of new technologies and machines such as a Muon Ring Cooler is essential. This project was to undertake a feasibility study of a compact gas-filled storage ring for 6D cooling of muon beams. The ultimate goal, in Phase III, was to build, test, and operate a demonstration storage ring. The preferred lattice for the storage ring was determined and dynamic simulations of particles through the lattice were performed. A conceptual design and drawing of the magnets were made and a study of the RF cavity and possible injection/ejection scheme made. Commercial applications for the device were investigated and the writing of the Phase II proposal completed. The research findings conclude that a compact gas-filled storage ring for 6D cooling of muon beams is possible with further research and development.
Date: October 31, 2005
Creator: Garren, A. & Kolonlo, J.
Partner: UNT Libraries Government Documents Department

Controlling the crossing angle in the SSC (Superconducting Super Collider)

Description: The colliding beams in the SSC must cross at a small angle, so that when the bunches pass each other away from the interaction point (IP), they are sufficiently separated to avoid disruptive beam-beam forces. However, the crossing angle is so small that the adjacent quadrupoles must be common to both beams. Only after passing through four common quadrupoles on each side of the IP, are the beams split by vertical dipoles into separate beamlines. In order to make the closed orbits of the two beams cross at a definite angle at the IP (within a range up to 150 {mu}rad), a series of correction dipoles are placed in the insertions. If these dipoles are excited in such a way as to control the closed orbits alone, the dispersion will be mismatched, reaching values of up to 50 cm in the arcs. This mismatch is due to the closed orbit displacements in the interaction region (IR) quadrupoles, causing them to act as bending magnets. Therefore, both the closed orbit and dispersion must be matched simultaneously. Solutions to this problem are presented. 6 figs.
Date: April 1, 1989
Creator: Garren, A. A. & Johnson, D. E.
Partner: UNT Libraries Government Documents Department

A Lattice for a Hybrid Fast-Ramping Muon Accelerator to 750 GeV

Description: We describe a lattice for accelerating muons from 375 GeV to 750 GeV. The lattice is a fast-ramping synchrotron with a mixture of fixed-field superconducting dipoles and warm dipoles, so as to have a high average bending field while still being able to rapidly change the average bending field as the beam momentum increases. For a 1.5 TeV center of mass muon collider, muons must be rapidly accelerated to 750 GeV. To accomplish this efficiently, we wish to make as many passes through the RF cavities as possible, while keeping the average RF gradients sufficiently high to avoid excess muon decays. A synchrotron where the magnets are very rapidly ramped has been envisioned as one option to accomplish this. The entire acceleration cycle takes place in less than 1 ms, presenting a technological challenge for the magnets. Clearly superconducting magnets cannot be ramped on this time scale, so instead room-temperature magnets will be ramped. To keep losses low, dipoles can use grain-oriented silicon steel, but quadrupoles will probably need to use more conventional steel, giving a lower maximum field for these high ramping rates. If we want to have a large average RF gradient and simultaneously make a large number of passes through the RF cavities, the average bending field must be high. To achieve such a large bending field while rapidly ramping magnets, it has been proposed to use a hybrid lattice consisting of interleaved superconducting dipoles and bipolar ramped dipoles. Due to the large single-bunch current and the relatively small apertures we desire (both because we would like to use high-frequency RF, and because power requirements and heating will be more reasonable for smaller aperture ramped magnets), collective effects are expected to be very significant. To reduce their effects, we propose to have strong synchrotron oscillations (a synchrotron ...
Date: September 6, 2011
Creator: Garren, A.A. & Berg, J.
Partner: UNT Libraries Government Documents Department

A Four Cell Lattice for the UCLA Compact Light Source Synchrotron

Description: The 1.5 GeV compact light source UCS proposed for UCLA must fit into a shielded vault that is 9.144 meters (30 feet) wide. In order for the machine to fit into the allowable space, the ring circumference must be reduced 36 meters, the circumference of the six cell lattice, to something like 26 or 27 meters. The four cell lattice described in this report has a ring circumference of 27.0 meters.
Date: March 12, 1999
Creator: Garren, A.A. & Green, M.A.
Partner: UNT Libraries Government Documents Department

Apiary B Factory Lattice Design

Description: The Apiary B Factory is a proposed high-intensity electron-positron collider. This paper presents the lattice design for this facility, which envisions two rings with unequal energies in the PEP tunnel. The design has many interesting optical and geometrical features due to the needs to conform to the existing tunnel, and to achieve the necessary emittances, damping times and vacuum. Existing hardware is used to a maximum extent.
Date: May 3, 1991
Creator: Donald, M.H.R. & Garren, A.A.
Partner: UNT Libraries Government Documents Department

APIARY B-Factory Separation Scheme

Description: A magnetic beam-separation scheme for an asymmetric-energy B Factory based on the SLAC electron-positron collider PEP is described that has the following properties: the beams collide head-on and are separated magnetically with sufficient clearance at the parasitic crossing points and at the septum, the magnets have large beam-stay-clear apertures, synchrotron radiation produces low detector backgrounds and acceptable heat loads, and the peak {beta}-function values and contributions to the chromaticities in the IR quadrupoles are moderate.
Date: May 3, 1991
Creator: Garren, A. & Sullivan, M.
Partner: UNT Libraries Government Documents Department

Hybrid Fast-Ramping Accelerator to 750 GeV/c: Refinement and Parameters over Full Energy Range

Description: Starting with the lattice design specified in [Garren and Berg, MAP-doc-4307, 2011], we refine parameters to get precise dispersion suppression in the straight sections and eliminate beta beating in the arcs. We then compute ramped magnet fields over the entire momentum range of 375 GeV/c to 750 GeV/c, and fit them to a polynomial in the momentum. We compute the time of flight and frequency slip factor over the entire momentum range, and discuss the consequences for longitudinal dynamics.
Date: March 2, 2012
Creator: S., Berg J. & Garren, A. A.
Partner: UNT Libraries Government Documents Department