Abstracts Brochure - 2nd International Particle Accelerator Conference

of measurements on various beam parameters.
Comparison of the results between the measurement
and the simulation is also presented.
Poster Panel 62
ID: 3909 - MOPS023
An Analytical Lagragian Model for Analyzing
Temperature Effects in Intense Non-neutral
Beams, Everton Granemann Souza, Antonio
Endler, Renato Pakter, Felipe Barbedo Rizzato (IF-
UFRGS, Porto Alegre) - High-intensity chargedparticle
beams are used in several areas of physics.
We can mention as an illustration, high-energy
colliders, particle accelerators and vacuum electron
devices. In all cases quoted above, the beam lose
particles in the acceleration process, between its
production to its final destination. These ejected
particles, generally, produce a surrounding structure
around the beam core, called halo. This undesirable
structure is seen in simulation as well as in actual
linacs, and its formation has been one of the main
sources of energy loss in the acceleration devices.
For this reason, the need for an advance in
understand the mechanism that produce the halo
becomes necessary. In view of the whole problem,
we contruct a 1D Lagrangian warm-fluid model for
describe the behavior of inhomogeneous chargedparticle
beam in solenoidal focusing magnetic field.
The equations of motion are derived for an adiabatic
process with a state equation originated from the
ideal gas law. In the end, the model is compared
with self-consistent simulation and is used to explain
emittance growth and jets of particle, even when the
system is out of equilibrium.
Sub Classification: D04 High Intensity in Linear
Accelerators
Poster Panel 63
ID: 4117 - MOPS010
Experimental Studies with Low Transition
Energy Optics in the SPS, Hannes Bartosik,
Theodoros Argyropoulos, Thomas Bohl, Stephane
Cettour Cave, Karel Cornelis, Yannis
Papaphilippou, Giovanni Rumolo, Benoit Salvant,
Elena Shaposhnikova, Jorg Wenninger (CERN,
Geneva) - The optics of the SPS can be tuned to
lower transition energy such that the slippage factor
at injection is raised by a factor of almost 3. From
theory, an increase of the intensity thresholds for
transverse mode coupling instabilities, longitudinal
coupled bunch instabilities and longitudinal
instabilities due to the loss of Landau damping can
be expected. In this paper, experimental studies with
�
19
LHC-type proton beams in the SPS with very high
intensities of up to 3.5e11 p/b on the flat bottom and
at 450 GeV/c are presented. In particular, the
measurements address the increase of intensity
thresholds and the achievable transverse emittances
in the new low gamma transition optics with respect
to the nominal SPS optics. The obtained results are
compared with numerical simulations.
Sub Classification: D05 Instabilities - Processes,
Impedances, Countermeasures
Poster Panel 64
ID: 3000 - MOPS078
Coaxial Wire Simulations of Ferrite Kicker
Magnets, Hugo Alistair Day (CERN, Geneva;
UMAN, Manchester), Michael John Barnes, Fritz
Caspers, Elias Métral, Benoit Salvant, Carlo Zannini
(CERN, Geneva), Roger Michael Jones (UMAN,
Manchester) - Fast kicker magnets are used to inject
beam into and eject beam out of the CERN
accelerator rings. These kickers are generally
transmission line type magnets with a rectangular
shaped aperture through which the beam passes.
Unless special precautions are taken the impedance
of the yoke can provoke significant beam induced
heating, especially for high intensities. In addition
the impedance can contribute to beam instabilities.
The results of longitudinal and transverse impedance
measurements, for various kicker magnets, are
presented and compared with analytical calculations:
in addition predictions from a numerical analysis are
discussed.
Sub Classification: D05 Instabilities - Processes,
Impedances, Countermeasures
Poster Panel 65
ID: 4127 - MOPS060
Simulation of Resistive Wall Instabilities in
CSNS/RCS, Liangsheng Huang (IHEP Beijing,
Beijing) - Rapid Cycling Synchrotron (RCS�of The
China Spallation Neutron Source (CSNS) is a high
intensity proton accelerator, with average beam
power of 100kW. The collective effects caused by
the coupling impedance may be the limit to beam
power. Based on the impedance estimation for
components on beam line, the resistive wall
impedance and its instability are more serious than
any other instability. In this paper, a simple resistive
wall wake field model is used to simulate the bunch
oscillation and instability growth rate. In this model,
the continuous resistive wall wake field is equivalent
to points wake field along the RCS, and long bunch
is sliced into many micro-bunches. By tracking the