Paper |
Title |
Other Keywords |
Page |
IT03 |
Single Pass Optical Profile Monitoring
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instrumentation, optics |
10 |
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- R. Jung, G. Ferioli, S. Hutchins
CERN, Geneva, Switzerland
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Beam profiles are acquired in transfer lines to monitor extracted beams
and compute their emittance. Measurements performed on the first
revolutions of a ring will evaluate the matching of a chain of
accelerators. Depending on the particle type and energy, these
measurements are in general performed with screens, making either use of
Luminescence or OTR [Optical Transition Radiation], and the generated
beam images are acquired with detectors of various types: CCD, CMOS, CID,
TV Tubes or Multi-Anode Photo-Multipliers. The principles, advantages and
disadvantages of both families of screens will be discussed in relation
with the detectors used. A possible evaluation method for luminescent
screens and beam test results will be presented. Finally other optical
methods used will be mentioned for completeness.
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PM01 |
Use of Optical Transition Radiation Interferometry for Energy Spread And Divergence Measurements
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optical diagnostics, transition radiation, electron beams, energy spread, divergence |
89 |
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- R.B. Fiorito, A.G. Shkvarunets
IREAP, Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD, USA
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OTR interferometry (OTRI) has been shown to be an excellent diagnostic
for measuring the rms divergence and emittance of relativistic electron
beams when the energy spread ∆γ/γ is less than the normalized rms
divergence σ = γΘrms. This is the case for most beams previously
diagnosed with OTRI. To extend this diagnostic capability to beams with
larger energy spreads, we have calculated the effects of all the
parameters effecting the visibility of OTR interferences, V; i.e. energy
spread, angular divergence, the ratio of foil separation to wavelength
ratio, d/λ and filter bandpass.
We have shown that:
- for a given ∆γ/γ, the sensitivity of V to σ
is proportional to the observation angle Θ0, the fringe
order n and the ratio d/λ;
- the sensitivity of V to ∆γ/γ is independent of Θ0
and n but is proportional to d/λ.
Thus, by adjusting d/λ, and choosing the appropriate fringe order,
one can separate out and measure both the energy spread and divergence.
However, the filter bandpass must decrease with Θ0 and n.
Results of our calculations will be given for various beams of interest.
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PM11 |
Beam Studies Made With The SPS Ionization Profile Monitor
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diagnostics, instrumentation, monitoring, SPS |
116 |
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- C. Fischer, G. Ferioli, J. Koopman, F. Roncarolo
CERN, Geneva, Switzerland
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During the last two years of SPS operation, investigations were pursued
on the ability of the SPS ionization profile monitor prototype to fulfill
different tasks. It is now established that the instrument can be used
for injection matching tuning, by turn to turn recording of the beam size
after the injection. Other applications concern beam size measurements on
beams ranging from an individual bunch to a nominal SPS batch foreseen
for injection into the LHC (288 bunches). By continuously tracking
throughout the SPS acceleration cycle from 26 GeV to 450 GeV the
evolution of parameters associated to the beam size, it is possible to
explain certain beam behavior. Comparisons are also made at different
beam currents and monitor gains with measurements made with the wire
scanners. Data are presented and discussed, and the possible
implementation of new features is suggested in order to further improve
the consistency of the measurements.
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PM13 |
The PS Booster Fast Wire Scanner
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heavy ion, instrumentation |
122 |
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- S. Burger, C. Carli, K. Priestnall, U. Raich
CERN, Geneva, Switzerland
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The very tight emittance budget for LHC type beams makes precise
emittance measurements in the injector complex a necessity. The PS
machine uses 2 fast wire scanners per transverse plane for emittance
measurement of the circulating beams. In order to ease comparison the
same type of wire scanners have been newly installed in the upstream
machine, the PS Booster, where each of the 4 rings is equipped with 2
wire scanners measuring the horizontal and vertical profiles.
Those wire scanners use new and more modern control and readout
electronics featuring dedicated intelligent motor movement controllers,
which relieves the very stringent real time constraints due to the very
high speed of 20 m/s. In order to be able to measure primary beams at the
very low injection energy of the Booster (50 MeV) secondary emission
currents from the wire can be measured as well as secondary particle
flows at higher primary particle energies during and after acceleration.
The solution adopted for the control of the devices is described as well
as preliminary results obtained during measurements made in 2002.
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PM14 |
Upgrade Of The ESRF Fluorescent Screen Monitors
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instrumentation, linac, luminosity |
125 |
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- K. Scheidt
ESRF, European Synchrotron Radiation Facility, Grenoble, France
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The ESRF injector system contains 23 Fluorescent Screen monitors: 4 in
the TL-1 transferline (200 MeV), 8 in the Booster, and 11 in the TL-2
transferline (6 GeV). They are based on Chromium doped Alumina screens
that are pneumatically inserted at 45o angle in the beam path with an
optical system, at 90o angle, collecting and focusing the emitted
light onto a low-cost CCD camera with standard 75Ω video output.
Serving mainly alignment purposes in the past 10 years, the present
upgrade aims at a 200 μm fwhm resolution for beam-size and profile
measurements. The particularity of the Alumina screen not in vacuum but
in atmosphere will be explained. Details of the mechanics, the optic
system and a cost-efficient way of light flux adjustment will be given.
The analysis of the factors determining the ultimate spatial resolution
will show that it is dominated by the screen characteristics. Results
obtained with different screen material will be presented.
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PM16 |
Wire Scanner Beam Profile Measurement For ESRF
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wire scanner, beam profile, transfer line, ESRF |
131 |
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- A.B. El-Sisi
NRC, Atomic Energy Authority, NRC, Plasma and Nuclear Fusion Dept., Cairo, Egypt
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Method of beam transverse profile measurement in accelerator by wire
scanner is wide spread in accelerator field. The wire scanner is used in
beam transfer lines of European Synchrotron Radiation Facility (ESRF) to
provide data for beam profiles, which is being used in emittance
measurements. The beam energy in the first transport line is 200 MeV and
the peak current is 25 mA. The purpose of the scanner is to provide
horizontal and vertical beam profiles. This work will discuss the
operation of the wire scanner, and the first results of the scanner in
ESRF. By changing the value of focus quad at (de focus quad = 18 A) we get
the emittance value for the vertical plane. The value is 1.5·10-6 mrad.
When we used this value to simulate our result we find that the
simulation gives good fitting with real values of vertical plane. Also by
changing the value of the focus quad at (focus quad = 10.46 A) we
get the emittance value for the horizontal plane. The value is 2·10-7
mrad. And we find that the simulation gives good fitting with real
values.
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PM26 |
A System For Beam Diagnostics in the External Beam Transportation Lines of the DC-72 Cyclotron
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diagnostics, instrumentation, cyclotron, medical accelerators, pick-up, DC-72 |
155 |
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- A. Gall
DNPT, FEI STU Bratislava, Slovakia
- G.G. Gulbekian, B.N. Gikal, I.V. Kalagin, V.I. Kazacha
JINR, FLNR JINR Dubna, Russia
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The isochronous four-sector Cyclotron DC-72 will serve as the basic
facility of the Cyclotron Center of the Slovak Republic in Bratislava. It
will be used for accelerating ion beams of H- to Xe up to energy of
72-2.7 MeV/nucleon.
In the present work a system for external beam diagnostics is presented,
which is intended for on-line acquisition of data on the main parameters
of accelerated beams (current, position, profile, emittance and energy
of the ion beams) to allow effective tuning of the accelerator operation
regime as well as ion beam transport along the transport lines through
the ion optical systems to physical targets and set-ups.
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PM27 |
Multifunction Test-Bench For Heavy Ion Sources
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diagnostics, instrumentation, heavy ion |
158 |
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- S. Barabin, V. Batalin, A. Kozlov, T. Kulevoy, R. Kuybida, D.A. Liakin, A. Orlov, V. Pershin, S. Petrenko, D. Selezniov, Yu. Stasevich
ITEP, Institute for Theoretical and Experimental Physics, Moscow, Russia
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The new test-bench for heavy ion sources has been created in ITEP. It is
planned to equip test-bench with a set of measurement devices to cover
wide range of beam widths, divergences, durations, currents etc. It will
provide measurements of different heavy ion beams parameters,
particularly, emittance and charge state distribution. The last parameter
may be measured both by the time-of-flight method and with the magnet
analyzer. Two emittance measurement devices will be installed. It will be
possible to use both slit/grid and CCD based "pepperpot" methods, which
will give advantages of combination of classical emittance measurements
with performance of the CCD based devices. The detailed description of
test-bench and its equipment is presented. The first results at MEVVA ion
source and beam investigations are discussed.
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PT23 |
Transverse Emittance Measurements at the Photo Injector Test Facility at DESY Zeuthen (PITZ)
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diagnostics, free-electron-laser, linac, transverse-dynamics, PITZ |
225 |
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