117708238
STACKTAIL MOMENTUM COOLING IN THE FERMILAB ANTIPROTON SOURCE
11644763
Mechanical and Electrical Design of the Fermilab Lithium Lens and Transformer System
A lithium lens focusing device will be used for the collection of 8 GeV antiprotons in the Fermilab Tevatron I Project. The details of the mechanical and electrical design of the Fermilab lens and its associated toroidal transformer are discussed. The lens, with a radius of 1 cm and length 15 cm, is expected to achieve gradients of 1000 T/m for a focal distance of 0.225 m. The gradient requires a current on the order of 5x105A, resulting in large electromagnetic and thermal stresses. The power supply discharge current and the effect of the inductance of the power leads and connections are minimized by the use of a toroidal matching transformer surrounding the lens itself.
46560389
Helium Refrigeration System and Cryogenic System for Superconducting Switchyard Magnets at Fermilab
The first Fermilab Satellite Refrigerator produced from commercially built components has been operated in the Switchyard in a stand alone mode. After some initial shakedown runs, it has been used to cool two magnetically opposed superconducting magnets in the external beam line to the Meson Laboratory. This equipment was installed as a test of the cryogenic system to be used in converting the entire major horizontal bend to superconducting magnets (currently containing 56 conventional 10 foot dipoles). We report here on the successful operation of the refrigerator, our operating experience with the cryo nic system, and the successful transport of 1.8 x 10'1 350 GeV protons per pulse through the magnets. The complete system was designed and built by Fermilab personnel. Process and component specification and design were shared by Fermilab and an independent consulting firm.1
38254483
Very High Precision Current Regulated Power Supplies for the Fermilab Antiproton Source
These Power Supplies were designed to power the accumulator and debuncher storage rings at the Fermi National Accelerator Laboratory Antiproton Source. The accumulator and debuncher are both large acceptance 8 GeV storage rings. The accumulator ring has the most stringent requirements since it will be required to store beams for periods in excess of twenty four (24) hours. In order to ensure long term beam stability, resonances up to order eleven (11) must be avoided. Because of this stringent tuned stability requirement, the power supplies which power the three main quadrupole and the main dipole busses must be extremely stable. Thus the current regulation specification for these power supplies is 10 PPM (0.001%) including differential and common mode ripple, long term drift, and line and load regulation.
115274892
Superconducting Delay LINE. (Transparencies Only)
21928269
Large Dynamic Range Beam Profile Measurement in a High Background Environment
Beam profile measurements using a scanning target and loss monitor in the Fermilab Main Ring extraction channel have long proved their usefulness as a diagnostic method in analyzing extraction problems. To extend these measurements to a sensitivity greater than in the present system a different technique has been employed. A simple three element particle telescope viewing the scanning target allows a sensitive measurement of the tail on the edges of the beam profiles as well as the relative particle densities of the extracted beam and the circulating beam in the Main Ring. Both these regions are of significant interest in understanding extraction losses. The details of the profile measurement technique, some results using the telescope and possible methods of improving the measurements are discussed.
120900374
Vertex operators and fusion rules in the free field realizations of WZNW models
Abstract We study the representation of chiral vertex operators for sl(N) WZNW models in the free field formalism. Exploiting the underlying quantum group structure of the free field resolution, we reduce the problem of constructing the infinite number of components of a chiral vertex to that of finding a single vector in a finite dimensional irreducible representation of U q ( sl (N)) . In particular this provides a new, purely algebraic, characterization of the fusion rules. We briefly summarize the analogous construction for finite dimensional algebras and use it as a guide. Our discussion is illustrated by explicit examples of vertices in sl(2) and sl(3) WZNW models.
14793101
Basic instrumentation for Hall A at Jefferson Lab
The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electro-and photo-induced reactions at very high luminosity and good momentum and angular resolution for at least one of the reaction products. The central components of Hall A are two identical high resolution spectrometers, which allow the vertical drift chambers in the focal plane to provide a momentum resolution of better than 2 x 10(-4). A variety of Cherenkov counters, scintillators and lead-glass calorimeters provide excellent particle identification. The facility has been operated successfully at a luminosity well in excess of 10(38) CM-2 s(-1). The research program is aimed at a variety of subjects, including nucleon structure functions, nucleon form factors and properties of the nuclear medium. (C) 2003 Elsevier B.V. All rights reserved.
120095260
Excitation of low lying natural parity levels in /sup 208/Pb by inelastic electron scattering
High resolution electron scattering measurements on /sup 208/Pb have been performed at 90/sup 0/ and 160/sup 0/ which allow the spatial reconstruction of transition charge densities and for the first time, transition current densities. The measurement covering the momentum transfer range of 0.5
118667423
Chiral ring in the 4-D W(3) string
I summarize some recent results obtained in collaboration with P.~Bouwknegt and K.~Pilch on the spectrum of physical states in $\cW_3$ gravity coupled to $c=2$ matter. In particular, it is shown that the algebra of operators corresponding to physical states -- defined as a semi-infinite (or BRST) cohomology of the $\cW_3$ algebra -- carries the structure of a G-algebra. This G-algebra has a quotient which is isomorphic to the G-algebra of polyvector fields on the base affine space of $SL(3,\CC)$. Details have appeared elsewhere. To appear (with title change) in the proceedings of the ``H.S. Green and A. Hurst Festschrift: Confronting the Infinite'' Adelaide, March 1994.
121837398
Longitudinal and Transverse Inelastic Electron Scattering from Fe 56
Inelastic-electron-scattering cross sections for /sup 56/Fe have been measured in the continuum region. The longitudinal and transverse inelastic response functions have been determined for vector momentum transfers, q, from 210--410 MeV/c and for energy losses 0<..omega.. < or = 220 MeV.