摘要:

In recent months the first beams have been introduced into the various injector subsystems of the Advanced Photon Source (APS). An overview will be given of the diagnostics results on beam profiling, beam position monitors (BPMs), loss rate monitors (LRMs), current monitors (CMs), and photon monitors on the low energy transport lines, positron accumulator ring (PAR), and injector synchrotron (IS). Initial measurements have been done with electron beams at energies from 250 to 450 MeV and 50 to 400 pC per macrobunch. Operations in single turn and stored beam conditions were diagnosed in the PAR and IS. ©1995 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.48068

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The beam diagnostic system in PLS storage ring, which is in commissioning now, is described. Components of the electron beam diagnostic systems are: 4 fluorescent screens for the first‐turn beam detection, injection screen monitor, dc current transformer, beam scraper, betatron and synchrotron tune measurement system, and 108 beam position monitors composed of button style pickup electrodes. Among 108 BPMs, 96 have narrow band receivers and 12 have wideband receivers. With narrow BPMs, we achieved more than 65dB input dynamic range and better than 5 &mgr;mrmsresolution. At every beamline front end, there is an x‐ray beam position monitor, composed of a pair of gold‐plated diagonal electrodes, for the beamline beam steering and fast local orbit steering. Transverse beam sizes will be measured with two linear image sensor arrays and a 2dCCD array. A sampling oscilloscope and an optical‐to‐electrical converter module with 17psrisetime will be used for the measurement of short bunch length. ©1995 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.48069

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

During the reconstruction of the ISOLDE on‐line mass separator facility at CERN one of the goals was the development and implementation of an efficient and user friendly beam observation system. The pick‐up devices used on the two mass separators and the beam lines are mainly Faraday cups, wire scanners and wire grids. Most of these items were specifically designed at ISOLDE, in particular, a linearly moving wire scanner. The controls, data handling and display are all integrated in the PC based control system and can be accessed under Windows like any other element of the entire machine. The strong points of this measuring system as well as the limitations of beam observation in a low energy radioactive beam facility are discussed. ©1995 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.48039

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The cooler synchrotron COSY, a synchrotron and storage ring for medium energy physics, is being used for internal and external target experiments since fall 1993. The cooler ring has delivered protons up to the design momentum of 3.3 GeV/c. In this paper some diagnostic tools in the COSY‐ring are described. Almost all diagnostic components are installed and tested with beam. Special emphasis is given to the tools and methods, needed for optimizing the extraction process. ©1995 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.48040

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

Filling LEP with trains of bunches separated of only 247 ns instead of the present eight equidistant bunches (at 11 &mgr;s intervals) has important implications for the use of beam instrumentation. The BPM system will be limited in its measuring capabilities. Most other instruments will not be able to identify bunches unless further developments are made in their timing and acquisition electronics. A review of the situation is presented together with the planned actions to cope with the observation of individual bunches in trains. ©1995 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.48041

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

Instrumentation for measurements of beam intensity, beam position and beam shape at the beam lines of the AGOR cyclotron is discussed. A non‐intercepting beam current transformer and a capactive pick‐up can be used down to 1 nA beam current. In addition to wire grids (measurement of secondary emission current), a very sensitive non intercepting profile monitor, based on ionization measurements of the residual gas in the beam pipe, is presented. ©1995 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.48042

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

Optical Transition Radiation (OTR) devices have unique properties that allow them to complement the diagnostic tools more commonly used in particle accelerators. CEBAF is designed to produce a continuous electron beam accelerated up to 4 GeV by recirculating it five times through two 400 MeV superconducting linacs. We present two OTR applications that cannot be performed with standard fluorescent screens. The goal of the first one is to provide a multiturn ‘‘viewer’’ using the backward OTR emitted from a 0.8 &mgr;m thick aluminum foil. The foil must be thin enough to keep most of the beam in the machine after each passage. Looking at the successive turns in the linacs on the same screen will provide a new diagnostic device to help tune the machine. Replacing the ceramic of the present viewers with an Al foil is relatively simple and inexpensive. The preliminary results in single pass are encouraging. The goal of the second OTR application is to measure the emittance of high current continuous beams (≊200 &mgr;A) of low emittance (5 10−9mrad) and size (≤50 &mgr;m rms). Standard fluorescent screens or wire scanners cannot withstand such an intense beam. ©1995 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.48043

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

Electron pulses generated at the Stanford SUNSHINE facility with (2–4.6)×108electrons per microbunch have been measured as short as 50 fs (rms). The bunch length is determined by optical autocorrelation via a far‐infrared Michelson interferometer using coherent transition radiation emitted at wavelengths longer than and equal to the bunch length. This frequency‐resolved autocorrelation method demonstrates a better sub‐picosecond resolving power than any existing time‐resolved method. The experimental setup and the results will be described. ©1995 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.48044

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The Synchrotron Radiation Monitor for both electrons and positron beams of DA&Fgr;NE, the LNF &Fgr;‐Factory, is described. The most important measurements the monitor needs to provide are: beam transverse dimensions, bunch length, beam transverse density, vertical and horizontal tunes. The source points are in two bending magnets, one of each rings, placed in a zero dispersion region. The collected radiation, in the visible range, is sent through two optical transfer lines to the same measurement bench placed in a dedicated laboratory outside the DA&Fgr;NE hall. The complete layout of the measurement bench and a detailed description of the detectors employed are presented. ©1995 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.48045

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

An experimental study of the transverse spatial distribution of the ELSA‐linac electron beam has been initiated to investigate halo‐producing mechanisms in the generation, acceleration and transport of high‐intensity, high‐brightness charged‐particle beams. In an experiment presented here the beam profile has been analysed over four decades using an imaging technique. This technique consists in putting an optical transition radiation screen on the beam path. The emitted light is transported through conventional optics to an intensified video camera. The beam‐profile behaviour is shown to be dependent on the current, the initial size and shape of the beam and on the transport configuration. ©1995 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.48046

出版商:AIP    

年代:1995

数据来源: AIP