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Microprocessor based beam loss monitor system for the AGS

Description: An array of 120 long radiation monitors (LRM) have been installed around the AGS. Each monitor is an extended coaxial ion chamber, 5 meters long, made from hollow core coaxial transmission cable pressured with argon. The LRM's are each connected to a low current preamplifier and voltage-to-frequency converter (VFC). The digital output of each channel is fed to a 16 bit counter chip which bridges the bus of an 8085 microprocessor. This circuit is connected to the AGS PD-10 for data taking or may function as a stand-alone unit. Various operating modes can be selected for data readout. System design and operating performance are described.
Date: January 1, 1979
Creator: Witkover, R.L.
Partner: UNT Libraries Government Documents Department

Tests of SEC stability in high flux proton beams

Description: The Secondary Emission Chamber (SEC) is used to measure the beam intensity in slow extracted beam channels of proton synchrotrons around the world. With the improvements in machine intensity, these monitors have been exposed to higher flux conditions than in the past. A change in sensitivity of up to 25% has been observed in the region around the beam spot. Using SEC's of special construction, a series of tests was performed at FNAL, BNL-AGS and CERN-PS. The results of these tests and conclusions about the construction of more stable SEC's are presented.
Date: January 1, 1979
Creator: Agoritsas, V. & Witkover, R.L.
Partner: UNT Libraries Government Documents Department

New beam instrumentation in the AGS Booster

Description: The AGS Booster was designed to accelerate beams from 2{times}10{sup 10} polarized protons to 1.5{times}10{sup 13} protons and heavy ions through Au{sup +33}. The range of beam parameters and the high vacuum, and radiation environment presented challenges for the beam instrumentation. Some interesting beam monitors in the Booster and transport lines, will be described. Where available, results will be presented. 21 refs., 7 figs.
Date: January 1, 1991
Creator: Witkover, R.L.
Partner: UNT Libraries Government Documents Department

Plants for H/sup -/ acceleration in the AGS Linac

Description: Since its commissioning in 1970, the 200 MeV Linac at the Brookhaven AGS has been capable of producing peak proton beam current of greater than 100 mA with pulse lengths up to 300 ..mu..sec at a repetition rate of 10 pulses/second. The linac typically runs at 5 pulses per second, providing a 60 mA pulse of 120 ..mu..sec duration every 1.6 to 2.4 seconds for conventional multiturn injection into the AGS. The intervening pulses of length up to 300 ..mu..sec are used by the radio-isotope production, chemistry and medical facilities. Preparations are now being made to inject and accelerate H/sup -/ ions in order to implement charge exchange injection into the AGS. This paper describes the aspects of this work leading to an H/sup -/ beam at 200 MeV.
Date: January 1, 1979
Creator: Barton, D.S. & Witkover, R.L.
Partner: UNT Libraries Government Documents Department

Beam instrumentation in the AGS Booster

Description: The AGS Booster was designed to accelerate low intensity (2 {times} 10{sup 10}) polarized protons, high intensity (1.5{times}10{sup 13}) protons and heavy ions through Au{sup +33}. Coping with this wide range of beams, the 3 {times} 10{sup {minus}11} Torr vacuum and the radiation environment presented challenges for the beam monitors. Some of the more interesting instrumentation design and performance during the recent Booster proton commissioning will be described.
Date: January 1, 1991
Creator: Witkover, R.L.
Partner: UNT Libraries Government Documents Department

Negative ion source tests for H/sup -/ injection at the Brookhaven AGS

Description: A magnetron ion source of Fermilab design has been adapted to provide an H/sup -/ beam of 40 mA for acceleration in the Brookhaven 200 MeV Linac and injection into the AGS. The source operates at a repetition rate of 5 Hz and produces pulses of up to 250 ..mu..sec duration. Source stability, beam current and emittance have been studied as a function of several external source parameters. Beam emittance has been measured for two values of field gradient in the combined function magnet following the source. Evidence of neutralization of the space charge potential of the H/sup -/ beam has been noted. In the focusing plane the emittance was smaller by a factor of 2 for the higher magnet gradient.
Date: January 1, 1981
Creator: Barton, D.S. & Witkover, R.L.
Partner: UNT Libraries Government Documents Department

Conversion of the AGS linac to H/sup -/ acceleration

Description: The AGS 200 MeV linac was converted to an H/sup -/ accelerator during the summer of 1982 using a magnetron-type source in the column of the second pre-injector pit. Because of the re-entrant electrode design, a 20 keV transport line was required to carry the beam to the first electrode. Several changes were made to the source which enhanced its performance over previous designs. The same H/sup -/ beam current is available at 2.75 times the duty factor with reduced deterioration of its output over several months of operation. The source, 750 keV transport, and linac modifications and performance will be presented.
Date: January 1, 1983
Creator: Witkover, R.L.; Barton, D.S. & Reece, R.K.
Partner: UNT Libraries Government Documents Department

The upgraded ring loss radiation monitorinng system at the AGS

Description: With the Booster the AGS will accelerate protons to 3 /times/ 10/sup 13/ per cycle, polarized protons at 10/sup 12/, and ions from Carbon to Gold at intensities from 50 to 3 /times/ 10/sup 9/. A loss monitoring system is being developed to facilitate tuning, and to reduce personnel radiation exposure by minimizing residual induced activity and by allowing remote monitoring of activity in the accelerator enclosure. The monitoring system must have a large dynamic range to monitor high intensity beam losses and to measure induced activity down to the level of a few mrad/hour. Various detectors are being evaluated, including ion chambers, proportional counters, and aluminium cathode electronmultipliers. Measurements of the prompt ionization distribution in the median plane at various energies from point targets at two representative locations in the accelerator lattice have been completed. Details of the monitoring system will be presented, as well as the experimental measurements of the prompt radiation field, and a comparable Monte Carlo calculation. 2 refs., 5 figs.
Date: January 1, 1989
Creator: Bennett, G.W.; Beadle, E.; Castille, V. & Witkover, R.L.
Partner: UNT Libraries Government Documents Department

Beam instrumentation in the AGS Booster

Description: The AGS Booster was designed to accelerate low intensity (2 {times} 10{sup 10}) polarized protons, high intensity (1.5{times}10{sup 13}) protons and heavy ions through Au{sup +33}. Coping with this wide range of beams, the 3 {times} 10{sup {minus}11} Torr vacuum and the radiation environment presented challenges for the beam monitors. Some of the more interesting instrumentation design and performance during the recent Booster proton commissioning will be described.
Date: December 31, 1991
Creator: Witkover, R. L.
Partner: UNT Libraries Government Documents Department

DESIGN OF AN IMPROVED ION CHAMBER FOR THE SNS.

Description: Ion chambers are in common use as beam loss monitors at many accelerators. A unit designed and used at FNAL and later at BNL was proposed for the SNS. Concerns about the ion collection times and low collection efficiency at high loss rates led to improvements to this unit and the design of an alternate chamber with better characteristics. Prototypes have been tested with pulsed beams. The design and test results for both detectors will be presented.
Date: May 6, 2002
Creator: WITKOVER,R.L. & GASSNER,D.
Partner: UNT Libraries Government Documents Department

Beam current monitoring in the AGS Booster and its transfer lines

Description: The new AGS Booster is designed to accelerate low intensity polarized protons and heavy ions, and high intensity protons. The wide range of beam parameters and the vacuum, thermal and radiation environment, presented challenges in the instrumentation design. This paper describes the problems and solutions for the beam current monitors in the Booster and its transport lines. Where available, results of the initial operation will be presented. 11 refs., 3 figs.
Date: January 1, 1991
Creator: Witkover, R.L.; Zitvogel, E. & Castillo, V.
Partner: UNT Libraries Government Documents Department

The AGS Booster beam loss monitor system

Description: A beam loss monitor system has been developed for the Brookhaven National Laboratory Booster accelerator, and is designed for use with intensities of up to 1.5 {times} 10{sup 13} protons and carbon to gold ions at 50-3 {times} 10{sup 9} ions per pulse. This system is a significant advance over the present AGS system by improving the sensitivity, dynamic range, and data acquisition. In addition to the large dynamic range achievable, it is adaptively shifted when high losses are detected. The system uses up to 80 argon filled ion chambers as detectors, as well as newly designed electronics for processing and digitizing detector outputs. The hardware simultaneously integrates each detector output, interfaces to the beam interrupt systems, and digitizes all 80 channels to 21 bits at 170 KHz. This paper discuses the design, construction, and operation of the system. 4 refs., 2 figs.
Date: January 1, 1991
Creator: Beadle, E.R.; Bennett, G.W. & Witkover, R.L.
Partner: UNT Libraries Government Documents Department

Conversion of the BNL 200 MeV Linac to H/sup -/ and polarized H/sup -/ acceleration

Description: Planning for the conversion of the AGS Linac to H/sup -/ acceleration was begun in 1979; installation was completed in 1983. Discussion of this work and of the operational experience will be presented. The AGS Polarized Beam Project was begun in 1980. The design of the new H/sup -/ polarized source, the low Energy Beam Transport line (LEBT), and Radio-Frequency Quadrupole (RFQ) will be described. Current status and future plans will be presented. 14 references, 5 figures.
Date: January 1, 1984
Creator: Witkover, R.L.; Alessi, J.; Barton, D.; Kponou, A.; Makdisi, Y. & McNerney, A.
Partner: UNT Libraries Government Documents Department

Design of the AGS Booster Ionization Profile Monitor

Description: The AGS Booster Ionization Profile Monitor (IPM) must operate in a vacuum of about 3 {times} 10{sup {minus}11} Torr. The ultra-high vacuum imposes certain requirements on detector gain and restrictions on construction techniques. Each detector is a two-stage microchannel plate with an integral substrate containing sixty-four printed anodes. Formed electrodes provide uniform collection fields without the use of resistors, which would be unacceptable in these vacuum conditions. An ultra-violet light calibrates the detector in its permanent mounting. An extra set of electrodes performs a first order correction to the perturbations imposed by the horizontal and vertical collection electrodes. This paper will present details of the design of the profile monitor. 4 refs., 2 figs.
Date: January 1, 1991
Creator: Stillman, A.N.; Thern, R.E.; Witkover, R.L. & Van Zwienen, W.H.
Partner: UNT Libraries Government Documents Department

Design and operation of the AGS Booster Ionization Profile Monitor

Description: The AGS Booster Ionization Profile Monitor (IPM) must operate in a vacuum of about 3 {times} 10{sup {minus}11} Torr. The ultra-high vacuum imposes certain requirements on detector gain and restrictions on construction techniques. Each detector is a two-stage micro-channel plate with an integral substrate containing sixty-four printed anodes. Formed electrodes provide uniform collection fields without the use of resistors, which would be unacceptable in these vacuum conditions. An ultra-violet light calibrates the detector in its permanent mounting. An extra set of electrodes performs a first order correction to the perturbations imposed by the horizontal and vertical collection electrodes. This paper will present details of the design of the profile monitor and recent operational results. 4 refs., 6 figs.
Date: January 1, 1991
Creator: Stillman, A.N.; Thern, R.E.; Van Zwienen, W.H. & Witkover, R.L.
Partner: UNT Libraries Government Documents Department

1. 5 GeV/c multiturn shaving extraction and its transport line for the Brookhaven AGS

Description: A system for fast shaving extraction at 1.5 GeV/c is implemented to extract the circulating beam in five turns. A numerical simulation is first carried out to determine the emittance and the rf structure of the extracted beam. This is followed by several machine study sessions which establish the optimal extraction configuration, confirm the emittance, and modify the transport line for low energy beam. Finally, a one-week run for the Neutrino Oscillation experiment demonstrates that the system is very stable and capable of delivering 7.5 x 10/sup 12/ p/sec with 70% extraction efficiency and 95% transport efficiency.
Date: January 1, 1979
Creator: Weng, W.T.; Blumberg, L.N.; Gill, E.; Soukas, A.; Witkover, R.L.; Egleman, E. et al.
Partner: UNT Libraries Government Documents Department

Beam instrumentation for the BNL Heavy Ion Transfer Line

Description: The Heavy Ion Transfer Line (HITL) was constructed to transport beams from the BNL Tandem Van de Graaff (TVDG) to be injected into the AGS. Because the beam line is approximately 2000 feet long and the particle rigidity is so low, 20 beam monitor boxes were placed along the line. The intensity ranges from 1 to 100 nanoAmps for the dc trace beam used for line set-up, to over 100 ..mu..A for the pulsed beam to be injected into the AGS. Profiles are measured using multiwire arrays (HARPS) while Faraday cups and beam transformers monitor the intensity. The electronics stations are operated through 3 Instrumentation Controllers networked to Apollo workstations in the TVDG and AGS control rooms. Details of the detectors and electronics designs and performance will be given.
Date: January 1, 1987
Creator: Witkover, R.L.; Buxton, W.; Castillo, V.; Feigenbaum, I.; Lazos, A.; Li, Z.G. et al.
Partner: UNT Libraries Government Documents Department

Charge exchange injection at the AGS

Description: The AGS has been brought into operation in October 1982 with multi-turn H/sup -/ charge exchange injection. The injection area of the AGS has been modified to bring the H/sup -/ beam from the 200 MeV linac through the main magnet fringe field to a stripping foil located within the magnet aperture. The injection system is described in detail and initial performance of the accelerator is reported.
Date: January 1, 1983
Creator: Barton, D.S.; Ahrens, L.A.; Gill, E.; Glenn, J.W.; Reece, R.K. & Witkover, R.L.
Partner: UNT Libraries Government Documents Department

Design and operation of the AGS Booster Ionization Profile Monitor

Description: The AGS Booster Ionization Profile Monitor (IPM) must operate in a vacuum of about 3 {times} 10{sup {minus}11} Torr. The ultra-high vacuum imposes certain requirements on detector gain and restrictions on construction techniques. Each detector is a two-stage micro-channel plate with an integral substrate containing sixty-four printed anodes. Formed electrodes provide uniform collection fields without the use of resistors, which would be unacceptable in these vacuum conditions. An ultra-violet light calibrates the detector in its permanent mounting. An extra set of electrodes performs a first order correction to the perturbations imposed by the horizontal and vertical collection electrodes. This paper will present details of the design of the profile monitor and recent operational results. 4 refs., 6 figs.
Date: December 31, 1991
Creator: Stillman, A. N.; Thern, R. E.; Van Zwienen, W. H. & Witkover, R. L.
Partner: UNT Libraries Government Documents Department

The AGS Booster Beam Position Monitor system

Description: To accelerate both protons and heavy ions, the AGS Booster requires a broadband (multi-octave) beam position monitoring system with a dynamic range spanning several orders of magnitude (2 {times} 10{sup 10} to 1.5 {times} 10{sup 13} particles per pulse). System requirements include the ability to acquire single turn trajectory and average orbit information with {plus minus} 0.1 mm resolution. The design goal of {plus minus} 0.5 mm corrected accuracy requires that the detectors have repeatable linear performance after periodic bakeout at 300 {degree}C. The system design and capabilities of the Booster Beam Position Monitor will be described, and initial results presented. 7 refs., 5 figs.
Date: January 1, 1991
Creator: Ciardullo, D.J.; Abola, A.; Beadle, E.R.; Smith, G.A.; Thomas, R.; Van Zwienen, W. et al.
Partner: UNT Libraries Government Documents Department

Design and performance of the Booster Beam Position Monitor system

Description: Instrumentation has bean built to measure heavy ion and proton beam orbits over an intensity range of 2 [times] 10[sup 10] to 1.5 [times] 10[sup l3] particles per pulse. Twenty-two horizontal and 24 vertical pairs of electrostatic Pickup Electrodes (PUEs), each with a built-in test port, are interfaced with wideband, gain selectable front end electronics. The resulting real-time signals are linearly related (both in amplitude and temporal response) to the sum and difference of the charge induced on each electrode due to passing beam. PUE signals (or their sum and difference) are available at any detector location for use by other Booster systems e.g., the Tune Meter, Transverse Damper, Radial loop control, etc. Data acquistion electronics at each, location integrate the processed front end signals over a selectable number of bunches, then digitize and transmit the integrated sum and difference to the host computer. Data normalization is done in the software, which also provides various orbit acquisition and display options to the user. This paper will describe the Booster Beam Position Monitor system, its performance objectives and the key design aspect used to meet these objectives. In addition, initial results will be presented.
Date: January 1, 1992
Creator: Ciardullo, D.J.; Abola, A.; Beadle, E.; Brennan, J.M.; Smith, G.A.; Thomas, R. et al.
Partner: UNT Libraries Government Documents Department

Design of the AGS Booster beam position monitor system

Description: The AGS Booster beam position monitor system must cover a wide range of beam intensity and bunch length for proton and heavy ion acceleration. The detector is designed to maintain 0.1 mm local tolerance following 300{degree}C bakeout. The electronics will be located in the tunnel, communicating via fiber optic links to avoid ground loops. The design will be described and test results for prototype units presented. 5 refs., 4 figs.
Date: January 1, 1989
Creator: Beadle, E.; Brennan, J.M.; Ciardullo, D.J.; Savino, J.; Stanziani, V.; Thomas, R. et al.
Partner: UNT Libraries Government Documents Department