Abstracts Brochure - 2nd International Particle Accelerator Conference

the cyclotron had been manufactured by KIRAMS.
KIRAMS is short for Korea Institutes of
Radiological and Medical Science.
Funding Agency National Research Foundation of
Korea
Sub Classification: T09 Room-Temperature
Magnets
Poster Panel 112
ID: 2686 - THPO004
An Active Power Filter Based on Wavelet
Analysis, Xiaoling Guo (Private Address, Beijing;
IHEP Beijng, Beijing) - As modern accelerator
demands a magnet supply with a much higher
stability, it is important to improve the quality of the
magnet supply. An effective method to improve the
output performance active power filter (APF)
applied in current supply is proposed. To lowdown
the harmonic constituents, the APF circuit generates
a harmonic current, which added to the current from
the main power supply, to countervail the ones in the
supply’s current. At end of this paper, a simulation
result is given to prove the effect of APF.
Sub Classification: T11 Power Supplies
Poster Panel 113
ID: 1926 - THPO006
A Digital Power Supply Control Model in Heavyion
Therapy Accelerator Based on Dual Nios
Cores, Rongkun Wang (Graduate University,
Beijing; IMP, Lanzhou), Youxin Chen, Daqing
Gao, Huaihai Yan, Zhongzu Zhou (IMP, Lanzhou) -
DC and Pulse is the basic running models of magnet
power supply in Heavy-Ion Therapy Accelerator.
According to the character of digital power supply
and the requirement of Pulse model. This paper
introduce a Digital Power Supply Control Model
(DPSCM) in Heavy-Ion Therapy Accelerator based
on dual Nios cores, which can meet the requirement
of two basic running models. The new method
develops a system on-chip based on dual Nios cores
by SOPC technology in the Altera EP2C35 FPGA.
Communication, data processing is completed by
one core and reference current setting is completed
by another core. Compared with traditional DPSCM,
the dual Nios cores run simultaneously and
cooperate well, and the system efficiency is
remarkably improved, further, cores in parallel can
realize reference waveforms switch in pulse model
effectively. This paper chooses a model machine in
Heavy-Ion Therapy Facility in Lanzhou (HITFiL) as
test bench. Experimental results indicate that the
system can realize the function of pulse model, and
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the stability and current error meet the design
requirements.
Sub Classification: T11 Power Supplies
Poster Panel 114
ID: 3387 - TUPS007
SIS100 Prototype Cryocatcher, Lars Bozyk,
Dieter H.H. Hoffmann (TU Darmstadt, Darmstadt),
Holger Kollmus, Peter J. Spiller (GSI, Darmstadt) -
The main accelerator, SIS100, of the FAIR-facility
will provide heavy ion beams of highest intensities.
Ionization beam loss is the most important loss
mechanism at operation with high intensity,
intermediate charge state heavy ions. A special
synchrotron design has been developed for SIS100,
aiming for hundred percent control of ionization
beam loss by means of a dedicated cold ion catcher
system. To suppress dynamic vacuum effects, the
cryo catcher system shall also provide a significantly
reduced effective desorption yield. The construction
and tests of a prototype cryo ion catcher is a work
package of the EU-FP-7 project COLMAT. A
prototype test setup including cryostat has been
constructed, manufactured and tested at GSI under
realistic conditions with heavy ion beams of the of
the heavy ion synchrotron SIS18. The design and
results are presented.
Funding Agency EU-FP-7 project COLMAT, FIAS
Sub Classification: T14 Vacuum Technology
Poster Panel 115
ID: 3149 - TUPS023
Secondary Electron Yield on Cryogenic Surfaces
as a Function of Physisorbed Gases,
Asena Kuzucan, Holger Neupert, Mauro Taborelli
(CERN, Geneva), Herbert Stoeri (IAP TUW, Wien)
- Electron cloud is a serious limitation for the
operation of particle accelerators with intense
beams. It occurs if the metal surface secondary
electron yield (SEY) is sufficiently high to promote
electron multiplication. At low surface temperature
SEY is strongly influenced by the nature of the
physisorbed gases and by the corresponding surface
coverage. These conditions occur in many
accelerators operating with superconducting
magnets and cold vacuum sections as for instance
LHC. In this work we investigated the variation of
secondary electron yield of copper, aluminium and
electro polished copper as a function of physisorbed
N2, CO, CO2, CH4, Kr, C2H6 at cryogenic
temperatures. Conditioning of after physisorption of
H2O on electro polished copper will also be
presented. The results of the various gases are