Talks in 2008
Jim Norem
Argonne National Laboratory
Abstract
Marco Danuso
Sant'Anna School (Pisa) and Fermilab
Abstract
Alan A. Hahn
Fermilab
Abstract
Tom Peterson
Fermilab
Abstract
Manoel Conde
Argonne National Laboratory
Abstract
Alexey A. Poklonskiy
Michigan State University
Abstract
Vsevolod (Seva) Kamerdzhiev
Randy Thurman-Keup
Manfred Wendt
Fermilab
Abstract
Mike Syphers,
FNAL
Janet Conrad, Columbia University
Abstract
Kirk McDonald
Princeton
University
Abstract
Steve Holmes
FNAL
Abstract
Mike Syphers
FNAL
Abstract
Alexander
Zlobin
FNAL
Abstract
Yoshihisa
Iwashita
Kyoto University
Abstract
Jim Patrick,
Brian Hendricks, and Charlie Briegel
Fermilab
Abstract
Emanuela Barzi
Fermilab
Abstract
An ongoing effort at FNAL and elsewhere focuses on the endeavor of making state-of-the-art magnets for present and future accelerators. The High Field Magnet and LARP Programs need high field dipoles and quadrupoles, and Muon Collider R&D requires very high field solenoids. In the last 10 years, within a Superconductor R&D program at TD, a large infrastructure, including two short sample test facilities, a cabling machine to fabricate Rutherford-type cables, and furnaces for heat treatment, was built upon this need with the mission to serve as an interface between materials and magnets. This superconductor R&D program encompasses the study of LTS beyond NbTi, and HTS materials. As a leading center for conductor technology, for LTS like brittle Nb3Sn and Nb3Al, our research and scientific studies have focused on the process of cable development because of the many different phenomena occurring in the round strand that can deeply modify their performance in magnets. For instance the Nb3Sn dipole magnet performance can be gravely compromised by flux jump instabilities, which we found to be inherent to high-Jc Nb3Sn conductors. For HTS solenoid applications, our program aims at monitoring state-of-the-art conductors, solving present challenges of tapes and wires, and developing appropriate cable and coil technologies. These studies, which are broad in spectrum and scope, will help us develop a most enriching vision for the future.
Raymond Fliller
III
Fermilab
Abstract
The A0 Photoinjector is a 16MeV electron linac used for Accelerator R&D. It consists of a 1.3 GHz copper RF gun and a TESLA type superconducting cavity. Through its history, multiple beam physics experiments have taken place. Most recently a transverse to longitudinal emittance exchange beamline has been installed. This beamline uses a copper 3.9 GHz deflecting mode or crab cavity between two doglegs to affect the exchange. Data taking for this experiment is underway. Various mechanisms may dilute this exchange or effect the measurement. In this talk we will discuss the theory and initial data taking for the emittance exchange, and the physics that can dilute it, such as Coherent Synchrotron Radiation. We will also discuss other R&D activities that have applications to other machines which may be built at Fermilab such as the ILCTA-NML.Valeri Lebedev
Fermilab
Abstract
Recent stacking rate records are the result of many improvements in Antiproton Source. Details of the work carried out during last 1.5 year and the accelerator physics behind them will be discussed.
Giulio Stancari
INFN Ferrara
Abstract
Francium is one of the best candidates for measurements of atomic parity violation and for the search of permanent electric dipole moments. These fundamental measurements rely on precision studies in atomic spectroscopy and on the development of magneto-optical traps. A radioactive francium beam facility has been commissioned at INFN's national laboratories in Legnaro, Italy. The physics of francium production and trapping will be discussed, together with some of the technical challenges involved and a summary of recent results. Several options are being considered for future upgrades of this unique facility, including the new concept of a recirculating-beam ion source, which combines ionization cooling of a stored primary beam with a thin internal production target.Riccardo de
Maria
CERN
Abstract
The seminar is focused on beam optics design studies on interaction region layouts for a LHC luminosity upgrade. Two layouts options "dipole first" and "quadrupole first" are analyzed and compared.Ralph Assman
CERN
Abstract
The Large Hadron Collider at CERN will store and collide proton and ion beams with unprecedented intensities and destructive potential. Small fractions of the beam can be lost during operation. These losses require highly efficient and robust collimation such that the accelerator is protected against quenches and damage. The loss-induced challenges for the LHC are reviewed and the collimation system is described. Special focus is put on future research requirements for collimation upgrades and on opportunities for inter-laboratory collaborations.
S.Yu. Kazakov
KEK
Abstract
The general principles, design solutions and performance of the high-power RF sources the author worked on are considered for both “warm” and SC versions of a linear collider. The problems of high–power RF windows for accelerator applications, as well as the several types of the new windows the author invented, are discussed. The power multiplication schemes and examples of the some exotic high RF power components the author developed for these schemes are described, namely mode launchers, mode converters, power dividers, phase shifters, etc. The design and test results of a new, inexpensive and simple sectioned high-power input coupler for the SC collider option, developed by the author for ILC SC cavities, are presented. Finally, the results of the work on an ultra-fast electrically-controlled L-band ferroelectric tuner, which allows fast coupling and phase control of the SC acceleration cavities, are presented.
November 14, 2007 (special seminar!)
Chris Tschalaer, Bill Franklin, Aleem Siddiqui and Fuhua Wang
MIT/Bates
Abstract
The talk will be split into four parts:Presentation
Angelo Dragone
Brookhaven
National Laboratory
Abstract
During the last ten years, the development of microelectronics for radiation detector applications has faced a big impulse. Starting from pure analog ASICs integrating a few channels designed according to the classical front end schemes, more and more functionalities have been added. Realtime processing of the signals, at first in the analog domain and lately in the digital one, arbitration and multiplexing schemes have been introduced to reduce the number of interconnections and the amount of information to transfer to the data acquisition systems. During this talk a few examples of architectures developed at Brookhaven National Lab during the last four years will be presented with the aim to give an overview of the groups' and personal expertise.
Mike Tartaglia
Fermilab
Abstract
The International Linear Collider reference design requires over 13000 magnets, of approximately 135 styles, which must operate with very high reliability. The Fermilab Main Injector represents a modern machine with many conventional magnet styles, each of significant quantity, that has now accumulated many hundreds of magnet-years of operation. We review here the performance of the magnets built for this machine, assess their reliability and categorize the failure modes, and discuss implications for reliability of similar magnet styles expected to be used at the ILC.
Linda Klamp Spentzouris
Illinois
Institute of Technology
Abstract
IIT is one of several universities in the Chicago area with faculty and graduate student research in the area of accelerator physics. The present status of graduate student projects on the topics of metamaterial-loaded waveguides and Booster space charge studies will be reviewed. The metamaterial-loaded waveguide work was motivated by the possibility of customizing the dispersion function of the loaded waveguide, with the potential of suppressing higher-order modes. Calculational work and preliminary experimental data will be discussed. A Booster space charge coupling study will be presented, along with a discussion of status and future plans.
Presentation
Sergey Strokov
University of
Hiroshima
Abstract
The crystals are good candidates to use them in a beam extraction device at J-PARC and in a beam collimation device at ILC. The results of the experiments on deflection of electrons and protons performed in Japan will be presented. The prospect of the future channeling experiments in Japan will be discussed as well.
Presentation
September 18, 2007
Abstract
Breakdown is a limiting factor in rf devices from cavities for particle accelerators to waveguides for tokomak heating and rf delivery. Modeling breakdown is challenging because of the need to handle the generation and behavior of impurities. Processes such as sputtering, charge exchange, multiple ionization, and radiation are all important, but are not typically handled in traditional breakdown codes. I will discuss how we are addressing the challenges above in two particle-in-cell codes: OOPIC Pro and VORPAL.
Presentation
Studies
of Charged Particle Beam Dynamics on
the Paul Trap Simulator Experiment (PTSX)
Moses
Chung
Plasma
Physics Laboratory, Princeton University
Abstract
At the high beam intensities envisioned in present- and next-generation accelerators, a fundamental understanding of the influence of collective processes and self-field effects on beam transport and stability properties must be developed. To address these issues experimentally, the Paul Trap Simulator Experiments (PTSX) device was proposed and constructed at the Princeton Plasma Physics Laboratory (PPPL). The PTSX device is a cylindrical Paul trap that simulates a long, thin charged-particle bunch coasting through a kilometers-long alternating-gradient (AG) magnetic transport system by putting the physicist in the beam’s frame-of-reference. The transverse dynamics of particles in both systems are described by similar equations, including all nonlinear space-charge effects. In this talk, descriptions of the PTSX device and diagnostics are given, related theoretical backgrounds are summarized, and experimental results on beam mismatch, transverse beam compression, random noise effects, and collective modes are presented. Experimental results are also compared with WARP particle-in-cell (PIC) simulations.
Presentation
August
30, 2007
Zachary Conway
ANL
Abstract
Multi-spoke-loaded
superconducting niobium accelerator cavities are being developed for
heavy-ion
accelerators with application to both cw and pulsed ion linacs
necessary for
several proposed accelerator facilities. Multi-spoke cavities
have been
developed to accelerate ions from protons through uranium over the
velocity
range spanning 0.35 < beta < 0.75. Recent results of cold
tests,
focusing on the mechanical properties and the dramatically-improved RF
performance will be presented.
Presentation
Lance Cooley
FNAL
Abstract
Superconducting
materials for RF linear accelerators have attracted renewed attention,
thanks
in large part to present and former Fermilab personnel who have
organized and
hosted a series of workshops in recent years. I will review the latest
of
these, held this past May, which marks an important expansion from a
regional
meeting into a truly national meeting with >70 attendees. The
workshop
focused on topics such as theoretical limits to superconducting RF,
understanding the basic materials science of niobium, surface
characterization
techniques, other superconducting materials, alternative processing
strategies,
and niobium processing and cavity fabrication. I will discuss
highlights from
each of these areas, and describe their potential impact on the ILC. In
addition, since niobium is an enabling technology for very high
gradient accelerators,
I will explore implications of workshop presentations for SRF science
in
general, including the possibility for generating gradients beyond the
limits
of niobium. An important by-product of the workshop expansion has been
recognition of basic work by funding agencies, and I will discuss
briefly my
opinion about future materials research.
Fanglei Lin
Indiana University
Abstract
Two
partial helical dipole snakes have been employed successfully to
overcome all
imperfection and intrinsic spin resonances in the AGS provided that the
vertical betatron tunes were maintained in
the spin tune
gap near the integer 9. However, the measured maximum 65% polarization
at the
AGS extraction energy shows still about 20% polarization loss comparing
with
the injected 82%. Except for the horizontal intrinsic resonances
introduced by
the two partial snakes, there were also polarization drop due to the
residual
vertical intrinsic resonances, partial snake resonances and orbit
distortion
where the vertical betatron tune beyonds
8.99. This talk presents the investigation of polarization of proton
beam in the
AGS, including the experimental results and simulations. Possible cures
of the
remaining beam polarization are also discussed.
Presentation
Resonant multi-turn extraction
project:
principle and experiments at the CERN Proton Synchrotron
Massimo
Giovannozzi
CERN
Abstract
Recently a novel approach to perform multi-turn extraction was proposed based on beam splitting in the transverse phase space by means of trapping inside stable islands. In addition to numerical simulations, aimed at assessing the feasibility of the proposed technique, an experimental campaign was launched since the year 2002 at the CERN Proton Synchrotron. During the year 2004 run, a high-intensity single-bunch beam was successfully split and the generated beamlets separated without any measurable losses. The underlying principle will be presented and discussed in details as well as generalizations of the method to multi-turn injection and the latest experimental results.
Presentation
TMCI
REVEALED BY
FREQUENCY ANALYSIS
OF HEADTAIL TRACKING DATA USING SUSSIX
E. Métral (work with G. Rumolo, B. Salvant and R.
Tomás)
CERN,
Abstract
Since 2003, high-intensity single-bunch proton beams with low longitudinal emittance have been affected by heavy losses after less than one synchrotron period in the CERN SPS. Measurements of the turn-by-turn evolution of the instability have been compared with HEADTAIL simulations, exhibiting a remarkly good agreement. In both cases, a travelling-wave pattern propagating along the bunch was clearly identified, which was believed to be the signature of a Transverse Mode Coupling Instability. Recently, using SUSSIX to analyze tracking data from HEADTAIL via frequency analysis, previous predictions from MOSES, which computes the coherent bunched-beam modes, have been confirmed. In particular, using the SPS beam parameters, a coupling between the azimuthal modes -2 and -3 is taking place. This regime of TMCI is more intricate than the one observed in the past with leptons as the proton bunches are much longer. The next step will be to perform measurements in the SPS to verify this prediction.
Presentation
June 21,
2007
Longitudinal
Emittance Control in the
CERN PS
Heiko
Damerau
CERN
Abstract
Thorough control of the longitudinal emittance is
essential
for the
acceleration of high intensity beams in the CERN PS.
Therefore, the longitudinal emittance must
be
increased in a controlled
way to avoid beam losses due to instabilities. The higher harmonic 200
MHz RF system (six cavities) used for these blow-ups has to generate a
total RF voltage which, for the most demanding blow-up, is comparable
to
the voltage of the principal RF system. After an introduction to the
CERN PS Complex and the RF manipulations needed to produce beams for
the
LHC and for the anti-proton decelerator (AD), measurements and
simulations of the longitudinal blow-up are presented.
Presentation
Status
of the LHC
Inner Triplets
Jim
Kerby
Fermilab
Abstract
The status of the LHC inner triplets will be described.
Parametric
studies
for a phase-one LHC upgrade based on Nb-Ti
Ezio
Todesco
CERN
Abstract
Several options for a luminosity upgrade based on Nb-Ti "long"
quadrupoles have been studied in the past years. In this seminar we
present a
parametric study aiming at finding the relations between the triplet
length, its
aperture, and the minimum beta functions that can be achieved in the IP
using
quadrupoles built with the LHC main dipole cable. We carry out the
electromagnetic design for apertures ranging from 100 to 140 mm,
extending the
results of previous work, and using the critical currents as measured
in the
LHC cable production. Issues related to forces and protection in these
large
aperture magnets are presented.
We then consider the hypothesis of a phase-one upgrade, where the
detectors are
not modified, and therefore the maximal goal is to double the
luminosity or to
allow a recovery from non-nominal parameters using stronger focusing.
We show
that a solution with 130 mm aperture and 34 m long triplet (i.e., 10 m
longer
than nominal) would allow reaching a beta function in the IP of 25 cm.
This
would also leave some clearance for removing the limitations in beam
intensity
due to the impedance of collimators. Finally, we show that this
additional
clearance also allows improvement of the field quality, thus reducing
the
nonlinearities arising from the large beta functions.
Accelerator
Division
Roger
Dixon
Fermilab
Abstract
Presentation
Craig Drennan
Fermilab
Abstract
To
better
control the beam position, tune, and chromaticity in the Fermilab
Booster
synchrotron, a new package of six corrector elements has been designed,
incorporating
both normal and skew orientations of dipole, quadrupole, and sextupole
magnets. The devices are under construction and will be installed
in 48
locations in the Booster accelerator. Each of these 288 corrector
magnets
will be individually powered. Each of the magnets will be
individually
controlled using operator programmed current ramps designed
specifically for
the each type of Booster acceleration cycle. This presentation
will
provide an overview of the corrector magnet installation in the
accelerator
enclosure, power and sensor interconnections, specifications for the
switch-mode power supplies, rack and equipment layouts, controls and
interlock
electronics, and the features of the operator interface for programming
the
current ramps and adjusting the timing of the system triggers.
Presentation
Recent
machine and beam
line optics developments in the Antiproton Source
Vladimir Nagaslaev
(Fermilab)
Abstract
Antiproton production at Fermilab is a multistage process that uses 2 cooling rings and more than a kilometer of beam lines. During recent years numerous efforts and developments were put forward in order to substantially increase the production rate.
One of important parts of these efforts was the optics developments, such as improving machines acceptance, optimizing beam parameters for the stochastic cooling and optical matching of the beam lines. The current status of this work and plans for the near future are presented.
Presentation
Experimental Optimization of
TTF2 RF Photoinjector
and Bunch Compressors
Yujong Kim,
Free Electron Laser Laboratory,
Duke University
Abstract
To develop various technologies for a future linear collider and the European X-ray Free Electron Laser, conversion of DESY TESLA Test Facility
(TTF) into its phase 2 (TTF2 / FLASH) was started in 2002. To get an FEL lasing and a saturation of FEL power within a 30 m long undulator, highly dense and cold beams with a high peak current, a low energy spread, and a low emittance should be sent to the undulator. In 2004, commissioning of a new L-band RF gun, a new superconducting booster linac (ACC1), and two new bunch compressors were started to supply suchlike beams. During this talk, speaker will shortly introduce TTF2, RF photoinjector, and bunch compressors. Then, speaker will talk about various commissioning experiences of TTF2 RF photoinjector and the first experimental demonstration of a strong emittance damping along the booster linac to generate a ultra-low normalized transverse emittance of about 1 mm.mrad for 1 nC and 4.4 ps rms long electron beams. Finally, speaker will talk about experimental optimization of TTF2 bunch compressors to generate femtosecond long electron beams.
Presentation
Accelerator Driven Nuclear Energy - The Thorium Option
Rajendran
Raja
Abstract
A Fast Chopper for the HINS
Robyn
Madrak