Session 8: Low and Intermediate Energy Accelerators and ... - CERN

ending magnet in the beam transport line to the
booster synchrotron. This magnet operates at 1 Hz with
a trapezoid current pattern. The 1-GeV electron beam
goes at the bottom of the current pattern to the
NewSUBARU or at the top of the pattern to the booster
synchrotron. In order to obtain the higher reliability of
the linac for the top-up operation, reinforcement of the
beam monitor systems, further improvement of RF
phase stability and upgrade of the control system were
required. BPM?s has been newly installed in energy
dispersion sections, and beam transport feedback
control is in development. The phase variation in the
RF system was reduced by the regulation of the gas
pressure in the waveguide of the klystrons drive
system. We re-engineered the VME systems to
maximize availability of the linac operation
considering its reliability, usability, expandability and
flexibility.
Type of presentation requested: Poster
Classification: [A08] Linear Accelerators
65-1143 - Laser Temporal Pulse Shaping
Experiment For SPARC Photoinjector
Carlo Vicario, Andrea Ghigo (INFN/LNF, Frascati
(Roma)), Simone Cialdi (INFN-Milano, Milano),
Massimo Petrarca (INFN-Roma, Roma), Ilario
Boscolo (Universita' degli Studi di Milano, MILANO)
Laser for driving high brightness photoinjector have to
produce UV square pulse which is predicted to be the
optimum profile for emittance compensation in
advanced photoinjectors. The longitudinal laser pulse
distribution, according to numerical simulations for the
SPARC photoinjector, must be square with rise and fall
time shorter than 1 ps and flat top variable up to 10 ps
FWHM. In this paper we report the results of pulse
shaping obtained using an acousto-optic (AO)
programmable dispersive filter (DAZZLER). The
DAZZLER was used to perform spectral amplitude and
phase modulation of the incoming 100 fs Ti:Sapphire
pulses. Because of the finite length of the crystal the
maximum duration of the shaped pulse is 6 ps. To
overcome this limitation we used a configuration in
which the laser pulses passed twice through the AO
filter. A dispersive glass section was also used to
lengthen the pulse with a single pass in the DAZZLER.
In this paper we report the experimental setup,
hardware description and time and frequency domain
measurements.
Type of presentation requested: Poster
Classification: [A08] Linear Accelerators
66-1147 - Design Studies of a high Current
Deuteron RFQ
Chuan Zhang, Alwin Schempp (IAP, Frankfurt-am-
Main), Jia-er Chen, Jia-Xun Fang, Zhiyu Guo
(PKU/IHIP, Beijing)
A 201.5MHz, 50mA deuteron RFQ is proposed for the
new neutron source project at Peking University,
China. Considering minimum beam losses, the limited
RF power and the demands of safety maintenance, design
studies have been performed with the ParmteqM and
Microwave Studio codes to optimize the structure design.
Results of a conceptual design with a compact structure and
high transmission efficiency is presented.
Mr. C.Zhang is supported by Gottlieb Daimler- und Karl
Benz-Stiftung & GSI, Germany
Type of presentation requested: Poster
Classification: [A08] Linear Accelerators
67-1285 - First Results of Pulsed Superconducting Halfwave
Resonators
Rolf Stassen, Ralf Eichhorn, Rudolf Maier, Gebhard Schug,
Raimund Tölle, Evgeny Zaplatin (FZJ/IKP, Jülich),
F.M. Esser, Bernhard Laatsch (FZJ, Julich)
A pulsed linac for the cooler synchrotron COSY was
projected based on superconductive half-wave resonators
(HWRs). The concept of single phased resonators is a great
challenge related to the requirement of accelerating protons
and deuterons up to a similar energy. A cryomodule, which
houses four cavities was designed in Cooperation with FZJ-
ZAT, taking into account the restricted space and the
special requirements of a linear accelerator. Two prototypes
of the 160MHz Half-Wave Resonators (HWRs) were built
at different companies. The fabrication differs slightly
concerning the top and bottom parts of the cavity as well as
the welding of the inner and outer conductor. First results of
warm and cold measurements will be presented. The
behaviour of the adjustable 4kW main coupler as well as the
mechanical tuner can be tested together with the HWR in a
new vertical test-cryostat.
Type of presentation requested: Poster
Classification: [A08] Linear Accelerators
68-1313 - Achievements of the High Current Beam
Performance of the GSI Unilac
Winfried Barth, Ludwig Dahl, Joerg Glatz, Lars Groening,
Simone Georgia Richter, Stephan Yaramishev (GSI,
Darmstadt)
The present GSI-accelerator complex is foreseen to serve for
the future synchrotron SIS100 as an injector for up to 1012
U28+ particles/sec. The High Current Injector of the Unilac
was successfully commissioned five years ago. An increase
of more than two orders of magnitude in particle number for
the heaviest elements in the SIS had to be gained. Since that
time many different ion species were accelerated in routine
operation. In 2001 a physics experiment used 2_109
Uranium ions per spill. In order to meet this request the
MEVVA ion source provided for the first time in routine
operation a high intense Uranium beam. The main purpose
for the machine development program during the last two
years was the enhancement of the intensity for Uranium
beams. Different hardware measures and a huge
investigation program in all Unilac-sections resulted in an
increase of the uranium intensity by a factor of 7. The paper
will focus on the measurements of beam quality, as beam
emittance and bunch structure for Megawatt-Uranium
beams. Additionally the proposed medium- and long-term
hardware measures will be described, which should gain in