EPAC08 - Classification:05 Beam Dynamics and Electromagnetic Fields/D01 Beam Optics

05 Beam Dynamics and Electromagnetic Fields

D01 Beam Optics - Lattices, Correction Schemes, Transport

Paper	Title	Page
MOZAG01	Simulations of the Emittance Compensation in Photoinjectors and Comparison with SPARC Measurements	21
	C. Ronsivalle, L. Giannessi, M. Quattromini ENEA C. R. Frascati, Frascati (Roma) A. Bacci, A. R. Rossi, L. Serafini INFN-Milano, Milano E. Chiadroni, M. Ferrario, L. Ficcadenti, D. Filippetto, V. Fusco, B. Marchetti, M. Migliorati, A. Mostacci, L. Palumbo, C. Vaccarezza INFN/LNF, Frascati (Roma) A. Cianchi INFN-Roma II, Roma
	FEL photoinjectors are based on the emittance compensation process, by which a high brightness beam can be accelerated without degradation. The experimental results obtained in the SPARC facility for which the beam dynamics has been extensively simulated confirm the theoretical predictions. The paper illustrates the most relevant beam dynamics results as well as a comparison between simulations and measurements.
	Slides
MOZAG02	Short Bunches in Electron Storage Rings and Coherent Synchrotron Radiation	26
	G. Wuestefeld BESSY GmbH, Berlin
	Significant progress has been made in recent years in achieving short bunches in third generation synchrotron light sources and the generation of coherent radiation. This talk will review the properties of the radiation and the associated beam dynamics, and will discuss optics issues and the limits of the available techniques.
	Slides
TUOBG03	Electron Beam Dynamics in the Long-pulse, High-current DARHT-II Linear Induction Accelerator	968
	C. Ekdahl, E. O. Abeyta, P. Aragon, R. D. Archuleta, G. V. Cook, D. Dalmas, K. Esquibel, R. J. Gallegos, R. W. Garnett, J. F. Harrison, E. B. Jacquez, J. Johnson, B. T. McCuistian, N. Montoya, S. Nath, K. Nielsen, D. Oro, L. J. Rowton, M. Sanchez, R. D. Scarpetti, M. Schauer, G. J. Seitz, H. V. Smith, R. Temple LANL, Los Alamos, New Mexico H. Bender, W. Broste, C. Carlson, D. Frayer, D. Johnson, C.-Y. Tom, C. P. Trainham, J. T. Williams NSTec, Los Alamos, New Mexico T. C. Genoni, T. P. Hughes, C. H. Thoma Voss Scientific, Albuquerque, New Mexico B. A. Prichard, M. E. Schulze SAIC, Los Alamos, New Mexico
	We are now operating the full-scale DARHT-II linear induction accelerator (LIA) at its rated energy, accelerating 2-kA electron beams to more than 17 MeV. The injector produces a beam pulse with a full-width at half maximum (FWHM) greater than 2.5 microseconds, and a ~0.5 microsecond rise time. This long risetime is deliberately scraped off in a special beam-head cleanup zone (BCUZ) before entering the 68-cell main accelerator. The accelerated electron beam pulse has a flat-top region where the final electron kinetic energy varies by less than 1% for more than 1.5 microseconds. We will discuss the tuning of the injector, BCUZ, and accelerator; and we will present data for the resulting beam transport and dynamics. We will also present beam stability data, which we will relate to previous stability experiments at lower current and energy. Carl Ekdahl et al. "Long-pulse beam stability experiments on the DARHT-II linear induction accelerator," IEEE Trans. Plasma. Sci. Vol. 34, 2006, pp. 460-466.
	Slides
THPC001	Synthesis of Optimal Nanoprobe (Linear Approximation)	2969
	S. N. Andrianov, A. A. Chernyshev, N. S. Edamenko, Yu. V. Tereshonkov St. Petersburg State University, Applied Mathematics & Control Processes Faculty, St. Petersburg
	High energy focused ion (proton) micro- and nanoprobes are intensively integrated to powerful analytical tool for different scientific and technological aims. Requirements for beam characteristics of similar focusing systems are extremely rigid. The value of demagnification for micro- and nanoprobes is the main optimality criteria, and as desirable value are in the range from 50 to 100 or even more. In the paper, we reconsider the basic properties of first order focusing systems from an optimal viewpoint. The matrix formalism allows us to formulate a nonlinear programming problem for all parameters of guiding elements. For this purpose there are used computer algebra methods and tools as the first step, and then some combination of special numerical methods. As a starting point for nanoprobe we consider so called “russian quadruplet”. On the next steps, we also investigate other types of nanoprobes. Some graphical and tabular data for nanoprobe parameters are cited as an example.
THPC003	Sum of Emittance in the Presence of a Linear Coupling	2975
	M. Aslaninejad, H. Ghasem IPM, Tehran
	In this article, the influence of linear coupling due to skew quadrupoles on the transverse equations of motion and emittances in accelerators is studied. We first introduce the definition of the transverse single particle emittances using the Floquet transformation in alternating gradient as well as the constant focusing rings, then in the presence of the linear coupling, due to skew quadrupoles we introduce the coupled differential equations governing the particles motion and try to solve them by a direct method and also using the normal modes of motion to find the relation between the two transverse emittances. Based on smooth approximation and using the normal modes* we solve the equations of motion of a test charged particle and derive two new formulas for the sum of the emittances, and the conditions under which this sum is invariant. P. J.Bryant, CERN Acclerator School, CERN, PROCEEDINGS, 94-01, Vol. I. *E. Metral, CERN/PS 2001-066(AE).
THPC004	Chromatic and Wakefield Effects in PSI-XFEL Linac	2978
	B. Grigoryan, G. A. Amatuni, V. M. Tsakanov CANDLE, Yerevan R. J. Bakker, Y. Kim, M. Pedrozzi, J.-Y. Raguin PSI, Villigen
	Detailed knowledge about the wakefield and chromatic effects on electron beam emittance is an important issue to preserve the natural emittance of the beam in linear accelerators for FEL. The study of these two effects for beam and accelerator components imperfections in PSI-XFEL S-Band linear accelerator is presented. Emittance dilution caused by the beam coherent oscillations, accelerating section and quadrupole misalignments is analysed. The residual chromatic emittance dilution of the corrected trajectory is evaluated.
THPC005	Conceptual Design of Booster Synchrotron forTPS	2981
	H. C. Chao, H.-P. Chang, P. J. Chou, C.-C. Kuo, G.-H. Luo, H.-J. Tsai, J. W. Tsai NSRRC, Hsinchu
	A six-folded concentric booster of 489.6 m with non-dispersive straights of length 5.8 m is designed for TPS storage ring of 518.4 m. The structure consists of modified FODO lattice with defocusing quadrupole fields built in bending magnets. The designed emittance is less than 10 nm-rad at 3 GeV. In this paper, the phenomenon during the ramping from 150 MeV to 3.0 GeV including the eddy current effect, the evolutions of beam emittance, energy spread, and bucket acceptance, will be discussed. In addition, closed orbit correction scheme, aperture request as well as injection and extraction schemes are described.
THPC006	Applications of a BPM-based Technique for Measuring Real Space Distributions in the Spallation Neutron Source Ring and Transport Lines	2984
	S. M. Cousineau, T. A. Pelaia, M. A. Plum ORNL, Oak Ridge, Tennessee
	The SNS accumulator ring and associated transport lines are designed to accumulate and transport up to 1.5·10¹⁴ ppp to a liquid mercury target for neutron spallation. Since commissioning, a dedicated effort has been put forth to characterize the lattice and beam dynamics at low intensity. Toward this goal, a BPM-based technique for measuring real space beam distributions at low beam intensities was developed. Recently, this technique has been used to diagnose and localize a strong source of coupling in the lattice, to verify and troubleshoot complementary diagnostics devices, and to provide data for code benchmarking. Other potential applications of this technique include investigations of single particle dynamics and resonances, studies of injection painting techniques, and possibly measurement of quadrupole power supply errors in the ring. In this paper we present the results of applying this technique to various situations in the SNS ring and transport lines, including the first ORBIT benchmarks of the SNS ring and RTBT. T. Pelaia et al, Nucl. Instr. And Methods, in progress.
THPC007	Permanent Magnet Skew Quadrupoles for the Low Emittance LER Lattice of PEP-II	2987
	F.-J. Decker, S. D. Anderson, D. Kharakh, M. K. Sullivan SLAC, Menlo Park, California
	The vertical emittance of the low energy ring (LER) in the PEP-II B-Factory was reduced by using skew quadrupoles consisting of permanent magnet material. The advantages over electric quadrupoles or rotating existing normal quadrupoles are discussed. To assure a high field quality a Biot Savart calculation was used to cancel the natural 12-pole component by using different size poles over a few layers. A magnetic measurement confirmed the high quality of the magnets. After installation and adjusting the original 12 skew and 16 normal quadrupoles the emittance contribution from the region close to the interaction point, which was the biggest part in the original design, was considerably reduced.
THPC008	Constants and Pseudo-constants of Coupled Beam Motion in the PEP-II Rings	2990
	F.-J. Decker, W. S. Colocho, M.-H. Wang, Y. T. Yan, G. Yocky SLAC, Menlo Park, California
	Constants of beam motion help as cross checks to analyze beam diagnostics and the modeling procedure. Pseudo-constants, like the betatron mismatch parameter or the coupling parameter det C, are constant till certain elements in the beam line change then. This can be used to visually find the non-desired changes, pinpointing errors compared with the model.
THPC010	Trajectory Correction in the Fermi@Elettra Linac	2993
	S. Di Mitri ELETTRA, Basovizza, Trieste A. Zholents LBNL, Berkeley, California
	The effect of the static magnetic field errors and misalignment of the magnetic elements and linac modules on the beam trajectory in the Fermi@elettra linac [1] has been studied. Analytical description has been used to guide simulations of the trajectory correction using three different techniques. A control over the residual R56 transfer matrix element along the linac lattice has been applied. The importance of the linac structural transverse wake field for a reliable prediction of the bunch centroid dynamics has been demonstrated. Transverse deviations of bunch slices along the electron bunch induced by the wake fields have been calculated. [1] S. Di Mitri, ST/M–07/01 (2007)
THPC011	The CR-RESR Storage Ring Complex of the FAIR Project	2996
	A. Dolinskii, O. E. Gorda, S. A. Litvinov, F. Nolden, C. Peschke, I. Schurig, M. Steck GSI, Darmstadt D. Obradors-Campos MICINN, Madrid
	In frame of the FAIR project (at GSI, Germany) the CR-RESR storage ring complex has been designed for efficient cooling, accumulation and deceleration of antiproton and rare isotopes beams. The complex consists of the Collector Ring (CR) and the accumulator / decelerator ring RESR. The large acceptance CR will be operated at three different optical modes, two of them providing fast pre-cooling of antiprotons and rare isotopes. This ring will be also used as an instrument for mass measurements of very short-lived nuclei when tuned to an isochronous mode. The RESR will be used as accumulator of the antiprotons by means of the stochastic cooling technique and as a decelerator of rare isotopes. The structure of the CR and RESR lattices and its ion optical properties are described in this contribution. The beam dynamics of these rings at different operation scenario are discussed.
THPC012	Longitudinal Beam Dynamics Studies for the FERMI@ELETTRA Linac	2999
	O. Ferrando, G. D'Auria ELETTRA, Basovizza, Trieste
	FERMI is a single-pass FEL project under construction at Sincrotrone Trieste Laboratory. It will be driven by the present warm S-band linac, upgraded by the addition of seven accelerating sections to bring its working energy up to 1.2 GeV. The goal of the project is to have an X-ray user facility covering the wavelength region between 100 -10 nm. The stringent constraints on the electron beam parameters required by FERMI, such as emittance, pulse to pulse energy and current stabilities, and time of arrival of the bunch at the input of the undulator chain, impose very stringent requirements on the parameters and operating conditions of the linac accelerating sections. To address the problem, i.e. evaluating the operating conditions of the machine and the flexibility of the adopted layout, beam dynamics studies with the LiTrack code have been performed. Here the results of different linac settings as well as the allowed variations in terms of RF phase and amplitude of the accelerating field are presented and discussed.
THPC013	Start to End Simulations of Transverse to Longitudinal Emittance Exchange at the A0 Photoinjector	3002
	R. P. Fliller, H. T. Edwards, J. Ruan Fermilab, Batavia, Illinois T. W. Koeth Rutgers University, The State University of New Jersey, Piscataway, New Jersey
	Various schemes to exchange the transverse and longitudinal emittance have been proposed (Cornacchia and Emma, Kim et.al). One scheme involves a deflecting mode RF cavity between two doglegs to exchange the horizontal and longitudinal emittances. This will produce a complete and uncoupled emittance exchange in the thin cavity limit using first order matrix optics. Various other effects, such as a finite length cavity, can leave the emittances coupled after the exchange and dilute the final emittances. Other effects such as space charge and synchrotron radiation can only be investigated through simulations. An exchange experiment is underway at the A0 Photoinjector at Fermilab. In this paper we present start to end simulations of the experiment using various codes to account for space charge and Coherent Synchrotron Radiation effects. Astra is used to simulate all of the straight sections, including the deflecting mode RF cavity. CSR track simulates the doglegs, and the spectrometer. The results of these simulations are compared with analytical approximations and preliminary data. The effect on the exchange is also discussed.
THPC015	Computational Beam Dynamics Studies for Improving the Ring Injection and Extraction Systems in SNS	3008
	J. A. Holmes, S. M. Cousineau, M. A. Plum, J. G. Wang ORNL, Oak Ridge, Tennessee
	The ring injection and extraction systems must function as designed in order for the Spallation Neutron Source (SNS) to achieve its specified performance. In commissioning and early operations we have encountered problems that have been traced to these systems. We experienced high beam losses in and around the injection dump, the rectification of which has necessitated significant study and development by a multidisciplinary team. The results include a number of enhancements of existing features and the addition of new elements and diagnostics. The problem in the extraction region stems from tilted beam distributions observed in the ring-to-target beam transport line (RTBT) and on the target, thus complicating the control of the beam-on-target distribution. This indicates the inadvertant introdution of x-y beam coupling somewhere upstream of the RTBT. The present paper describes computational studies, using the ORBIT Code, addressed at the detailed understanding and solution of these problems.
THPC016	Beam Optics of the PEFP Modified Beam Lines	3011
	J.-H. Jang, Y.-S. Cho, B. Chung, H.-J. Kwon KAERI, Daejon
	The 100 MeV Linac of the Proton Engineering Frontier Project (PEFP) is designed to supply 20 MeV and 100 MeV proton beams to user groups. In order to extract 20 MeV proton beams, a 45 degrees bending magnet is installed after 20 MeV DTL tank. The extracted proton beams are separated into five target rooms via a AC bending magnets. For 100 MeV beams, we use the same distribution schemes. Recently, the layout of the beam lines are modified to be short and compact. The work summaries the beam optics calculation of the modified beam lines.
THPC017	Optimisation of a Beam Transfer FODO Line	3014
	J. B. Jeanneret, H.-H. Braun CERN, Geneva
	With in view the design of the CLIC long transfer lines, we developed a formal approach for the optimisation of a straight FODO line. Optimum phase advance and cell length depending on beam parameters are derived for power consumption, overall cost and sensitivity to quadrupole misalignment.
THPC018	Beam Dynamics Issues in the CLIC Long Transfer Line	3017
	J. B. Jeanneret, E. Adli, A. Latina, G. Rumolo, D. Schulte, R. Tomas CERN, Geneva
	Both the main beam and the drive beam of the CLIC project must be transported from the central production site to the head of the main linacs over more than twenty kilometres. Over such distances chromatic aberrations are substantial. With long distances and large beam currents, detuning and instabilities associated to ion production and multi-bunch resistive wall effects must also be considered. These effects are quantified and simulated. Based on these results, we propose a baseline design for these two lines.
THPC020	Emittance Exchange at the Fermilab A0 Photoinjector	3020
	T. W. Koeth Rutgers University, The State University of New Jersey, Piscataway, New Jersey L. Bellantoni, H. T. Edwards, R. P. Fliller, A. H. Lumpkin, J. Ruan Fermilab, Batavia, Illinois
	A transverse to longitudinal emittance exchange experiment is underway at the A0 Photoinjector at Fermilab. Our scheme employs a TM110 deflecting mode RF cavity between two magnetic doglegs proposed by Kim et. al. The beamline has been installed, characterization of the beamline is complete and data taking has begun. In this paper we report on efforts to date to observe the transverse to longitudinal emittance exchange. Measurements will be compared to analytical predictions and simulations.
THPC021	Investigations on a Q0 Doublet Optics for the LHC Luminosity Upgrade	3023
	E. Laface, W. Scandale, E. Y. Wildner CERN, Geneva C. Santoni Université Blaise Pascal, Clermont-Ferrand
	The Q0 scheme of the LHC insertion region is based on the introduction of a doublet of quadrupoles at 13 meters from IP. We present here the doublet optics and the magnets layout such as gradients, lengths, positions and apertures. In this scheme we show the gain in luminosity and chromaticity, with respect to a nominal layout with β=0.25 (i.e. LHC phase 1 upgrade) and β=0.15 m, due to a smaller beta-max. We show the alignment tolerance and the energy deposition issues, in Q0A-Q0B. We also consider shielding the magnets with liners. The capability of Q0 optics to limit the β function could be exploited after the LHC Phase 1 upgrade in order to reduce the β* below 0.25 m, leaving the upgraded triplet unchanged.
THPC023	Optimization of the AGS Superconducting Helical Partial Snake Strength	3026
	F. Lin, H. Huang, A. U. Luccio, T. Roser BNL, Upton, Long Island, New York
	Two helical partial snakes, one is superconducting (called cold snake) and one is normal conducting (called warm snake), have preserved the polarization of proton beam up to 65% at the AGS extraction energy with the inject 82% polarization. In order to overcome the spin resonances, stronger partial snake is required. However, the stronger partial snake, the more titled stable spin direction that results in stronger horizontal intrinsic resonance. The balance between raising the spin tune gap generated by the snakes and reducing the titled stable spin direction has to be considered to maintain the polarization. Because the magnetic field of the warm snake is constant, only the cold snake with a maximum 3T magnetic field can be varied to find out the optimized snake strength. The paper presents the simulation results from the spin tracking with different cold snake magnetic fields. Some experimental data are also analyzed.
THPC024	Closed Orbit Correction at the LNLS UVX Storage Ring	3029
	L. Liu, R. H.A. Farias, X. R. Resende, P. F. Tavares LNLS, Campinas
	The orbit correction of stored electrons in the LNLS storage ring often needs a few iterations to converge to the smallest distortion. This is caused in part by the residual coupling between transverse planes. This coupling effect can be included in the correction algorithm leading to the best orbit in just one iteration. However, in the LNLS ring, the number of monitors equals the number of vertical correctors but surpasses the number of horizontal correctors. This means that the vertical orbit can be corrected to zero at the position monitors in the decoupled situation but the horizontal orbit cannot. For the coupled case, the incapacity of zeroing the horizontal orbit leaks into the vertical plane. This problem can be addressed by the eigenvector method with constraints.
THPC025	Further Advances in Understanding and Optimising Beam Dynamics in the Diamond Storage Ring	3032
	I. P.S. Martin, R. T. Fielder, E. C. Longhi, B. Singh Diamond, Oxfordshire R. Bartolini JAI, Oxford
	We report the results of recent beam dynamics studies of the Diamond storage ring. These studies were aimed at both improving our understanding of the machine operation as well as establishing a reliable, well corrected lattice with long lifetime and high injection efficiency suitable for later top-up operation. Particular attention has been given to measuring and controlling the linear optics of the lattice, to determining the various contributions to the overall beam lifetime and to optimising the sextupole strengths for good on and off momentum dynamic aperture. For each topic, detailed comparisons with model predictions are also described.
THPC026	Measurement of Complex Coupling Driving Term of Linear Difference Resonance Using Turn-by-turn Beam Position Monitors	3035
	M. Masaki, K. Soutome, S. Takano, M. Takao JASRI/SPring-8, Hyogo-ken
	X-Y emittance coupling is one of the important measures of beam quality in an electron storage ring for high brilliant light source. We have developed a method of measuring complex coupling driving term C of linear difference resonance using turn-by-turn beam position monitors (BPMs), assuming the perturbation theory with the single resonance approximation. Since both amplitude and phase of the driving term are derived, we can uniquely determine the strength of two-degree-of-freedom skew quadrupole magnets for correction of the linear resonance coupling. Before the correction, the driving term was measured by the developed method at the SPring-8 storage ring where small skew quadrupole components are distributed as error magnetic fields. On the other hand, the linear resonance coupling was corrected using the counter skew quadrupole magnets, the strength of which was adjusted to minimize vertical beam size near the linear difference resonance. The measured driving term C was broadly consistent with the counter term calculated from the adjusted strength of skew quadrupole magnets for the coupling correction.
THPC027	Pulsed RF Accelerator of Electrons with Beam Recirculation	3038
	V. V. Mytrochenko, M. I. Ayzatskiy, P. Gladkikh, V. A. Kushnir, A. Opanasenko, A. Y. Zelinsky NSC/KIPT, Kharkov S. Chemerisov, D. Ehst ANL, Argonne, Illinois
	We discuss the project of upgrading existent 20 MeV L-band electron linac at Argonne National Laboratory aimed at electron energy increasing. It is shown that the proposed beam recirculation will provide on the accelerator output an electron beam with a pulse current 0.5 A and energy of particles 45 MeV. Problems of stability of recirculating beam are discussed.
THPC028	High Energy Beam Transport Line for the IFMIF-EVEDA Accelerator	3041
	C. Oliver, B. Brañas, A. Ibarra, I. Podadera Aliseda CIEMAT, Madrid N. Chauvin, A. Mosnier, D. Uriot CEA, Gif-sur-Yvette
	The IFMIF-EVEDA accelerator will be a 9 MeV, 125 mA cw deuteron accelerator which will verify the validity of the design of the future IFMIF accelerator. A transport line is necessary to handle the high current beam from the DTL exit up to the beam dump. This line must produce the beam expansion to obtain an acceptable power density at the beam dump. Therefore the design of the transport line must consider the geometry and power handling capacity of the beam dump, the space requirements for diagnostics and the restrictions on the maximum length of the line. In addition, a bending magnet is required in order to avoid excessive irradiation of the diagnostics and line elements by neutrons and gammas produced at the beam dump and to perform energy spread measurements. In this contribution, the preliminary design of the high energy beam transport line will be presented. The results of a sensitivity study to the input beam and line elements errors will also be discussed.
THPC030	Simulation Studies of Correlated Misalignments in the ILC Main Linac and the Influence of Ground Motion	3044
	F. Poirier, D. Kruecker, I. Melzer-Pellmann, N. J. Walker DESY, Hamburg
	Component misalignments are an important source of emittance dilution in the main linac of the International Linear Collider (ILC). The impact of static uncorrelated alignment errors has been widely studied with various simulation codes and several beam based alignment algorithms. For a realistic scenario one has to take into account that the survey and alignment process will introduce correlations between the component errors. In the present paper we study the performance of the Dispersion Matched Steering (DMS) technique for the case of such correlated misalignments. Different models for the correlations are investigated including a proposed alignment strategy for the ILC main linac* which has been implemented into the Merlin C++ library*. In addition to the initial static errors, dynamic errors due to ground motion will produce an emittance growth with time. For this case we have also investigated the stability of DMS tuning over time. Kiyoshi Kubo, private communication ** Merlin - A C++ Class Library for Accelerator Simulations; http://www.desy.de/~merlin.
THPC032	Vertical Beam Size Reduction via Compensation of Residual Transverse Coupling	3047
	T. F. Roque, X. R. Resende, P. F. Tavares LNLS, Campinas
	The Brazilian Synchrotron Light Source (LNLS) is currently constructing a beamline which will make use of the radiation produced by the EPU installed in the storage ring (SR) in 2007. Various force tasks have been triggered by this new beamline in order to achieve required beam properties and stability. One of these tasks has to do with reducing the SR's vertical beam size at the straight section where the EPU is located, hence improving the radiation brilliance from the EPU. This report will describe our recent efforts in understanding and controlling what residual effects there are in the ring that dominate the ring's vertical beam size. In particular, we study the effects of residual coupling perturbations on the beam size through the transfer matrix formalism which, we argue, is the most appropriate. A beam model including transverse linear coupling is validated with measured closed orbit response functions. By Analyzing this model we are able to propose new skew quadrupole elements to the SR that might reduce the vertical beam size at the EPU section and we can infer the validity of results with a pinhole beam imaging system which we have available in our diagnostic beamline.
THPC033	Global Optimization of the Magnetic Lattice Using Genetic Algoritihms	3050
	D. Robin, F. Sannibale, C. Steier, W. Wan, L. Yang LBNL, Berkeley, California
	The traditional process of designing and tuning the magnetic lattice of a particle storage ring lattice to produce certain desired properties is not straight forward. Often solutions are found through trial and error and it is not clear that the solutions are close to optimal. In this paper we employ a technique we call GLASS (GLobal scan of All Stable Settings) that allows us to rapidly scan and find all possible stable modes and then characterize their associated properties. In this paper we illustrate how the GLASS technique gives a global and comprehensive vision of the capabilities of the lattice. In a sense, GLASS functions as a lattice observatory clearly displaying all possibilities. The power of the GLASS technique is that it is very fast and comprehensive. There is no fitting involved. It gives the lattice designer clear guidance as to where to look for interesting operational points. We demonstrate the technique by applying it to two existing storage ring lattices - the triple bend achromat of the ALS and the double bend achromat of CAMD. We extend the analysis to more complex lattices using multiobjective evolutionary analysis.
THPC034	Correction the Round Beam Lattice of VEPP-2000 Collider Using Orbit Response Technique	3053
	A. L. Romanov, D. E. Berkaev, A. N. Kirpotin, I. Koop, E. Perevedentsev, Yu. A. Rogovsky, P. Yu. Shatunov, D. B. Shwartz BINP SB RAS, Novosibirsk
	Round colliding beams option in VEPP-2000 puts a number of strict requirements on the collider lattice. Orbit Response Matrix (ORM) technique is a versatile tool for lattice analysis and correction. For linear optical function study and correction, the orbit response to the dipole correctors is collected and processed, while for the orbit correction the quadrupole trimming is used. Theoretical and experimental responses of closed orbit on the same perturbations are compared to determine the most probable deviations of chosen parameters from its project values.
THPC036	Model Based Orbit Correction in a Diagnostics Deficient Region	3056
	A. P. Shishlo, A. V. Aleksandrov ORNL, Oak Ridge, Tennessee
	A method is presented for an orbit correction in a region where the number of beam position monitors is much less than the number of possible trajectory distortions points (quads). The method was developed for the Coupled Cavities Linac (CCL) part of the Spallation Neutron Source (SNS) linac. The orbit correction is very important in this region to minimize losses and activation, but the usual orbit correction method did not work here. The new method is based on a usage of a realistic online model. The parameters of the model were defined by multidimensional fitting procedure with a substantial array of measured trajectories in CCL. The procedure of parameters finding, model, and results are discussed.
THPC037	Studies of Orthogonal Bumps for ILC Main Linac	3059
	N. Solyak Fermilab, Batavia, Illinois S. A. Glukhov BINP SB RAS, Novosibirsk
	To preserve small vertical emittance of the beam in ILC main linac a few beam-based alignment techniques were proposed and studied in recent years. Dispersion and wakefield bumps are one of the effective tool for final tuning of the machine. One of the modifications of bumps is so called orthogonal (or SVD) bumps, proposed for CLIC. In paper we present study of orthogonal bumps performances for final alignment of the ILC main linac.
THPC038	Beam Dynamic Simulations of the New Polarized Electron Injector of the S-DALINAC	3062
	B. Steiner, W. Ackermann, S. S. Franke, W. F.O. Müller, T. Weiland TEMF, Darmstadt R. Barday, C. Eckardt, R. Eichhorn, J. Enders, C. Hessler, Y. Poltoratska, A. Richter, M. Roth TU Darmstadt, Darmstadt
	Aiming at an extension of the experimental possibilities at the Superconducting Darmstadt electron linear accelerator S-DALINAC, a polarized gun is going to be constructed at the moment. The new injector will be able to supply polarized electrons with kinetic energy in the 100 keV range and should add to the present unpolarized thermionic 250 keV source. The design requirements include a polarization degree of at least 80%, a mean current intensity of 60 μA and a 3 GHz cw time structure. The gun part is simulated in CST MAFIA whereas subsequent beam dynamics simulations are performed in V-Code. Initial conditions for the V-Code’s moment approach are extracted from the CST MAFIA simulations. The injector consists of short triplets, an alpha magnet, a Wien filter, a Mott polarimeter, a chopper/prebuncher system and beam diagnostic elements. For the simulations, the 3D electromagnetic fields of the beam line elements are used by means of a Taylor series expansion of variable order. All components except the chopper and a collimator is represented in the simulations. Recent beam dynamic results will be presented.
THPC040	Comparative Analysis of Different Kinds of Effects in the Nanoprobe	3065
	Yu. V. Tereshonkov, S. N. Andrianov St. Petersburg State University, Applied Mathematics & Control Processes Faculty, St. Petersburg
	Different kinds of parasitic effects in a nanoprobe are investigated. In this paper we consider the focusing system of nanoprobe, which consists of quadrupole lenses, but some results are also discussed for solenoids as focusing elements. The results of the similar analysis make it possible to design a number of goal-seeking strategies for selecting the optimal beam line structure. The influence of different linear and nonlinear aberrations is investigated using analytical and numerical methods and tools. For this purpose we present the beam line propagator based on a matrix formalism for Lie algebraic tools. In conclusion, some results of fulfilled modeling are analyzed.
THPC041	Closed Orbit Correction and Orbit Stabilization Control for TPS Storage Ring	3068
	H.-J. Tsai, H.-P. Chang, H. C. Chao, P. J. Chou, K. T. Hsu, C.-C. Kuo, W. T. Liu, J. W. Tsai NSRRC, Hsinchu
	TPS is a 3 GeV synchrotron storage ring proposed in Taiwan. The designed natural emittance with slightly positive dispersion in the straight sections is less than 2 nm-rad. With 1% emittance coupling, the beam size in horizontal and vertical plane are 120/5 micron in the short straight sections, respectively. The beam position stability requirements are 10% of the beam sizes, i.e., 12/0.5 micron in the horizontal/vertical plane. The closed orbit distortions due to alignment displacement and magnetic field errors are simulated. The distribution of beam position monitors and the location of slow and fast correctors are proposed and the level of achievement is shown.
THPC042	Uncoupled Achromatic Tilted S-bend	3071
	N. Tsoupas, A. Kayran, V. Litvinenko, W. W. MacKay BNL, Upton, Long Island, New York
	A particular section of one of the electron beam transport lines, to be used in the e-cooling project* of the Relativistic Heavy Ion Collider (RHIC), is constrained to bend the beam simultaneously in both the horizontal and vertically planes and also be achromatic in both planes. The simultaneous horizontal and vertical achromatic bend is accomplished by rotating, about the longitudinal axis of the beam, the dipole and quadrupole elements of this section of the line. However such a rotation of the magnetic elements may couple the transported beam through the first order beam transfer matrix (linear coupling). In this paper we investigate for a sufficient condition, that the first order transport matrix (R-matrix) can satisfy, under which such a section of a beam transfer line is both achromatic and also constrains the beam at the exit of the line to emerge linearly uncoupled. We also provide a complete solution for the beam optics, of this part of the beam transfer line, which satisfies achromaticity and no first order beam coupling. *htpp://www.bnl.gov/cad/eRhic/Documents/AD_Position_Paper_2007.pdf
THPC044	Accurate Calculation of Higher Order Momentum Compaction Factor in a Small Ring	3074
	L. Wang, G. Feng, W. Li, L. Liu, C.-F. Wu, H. Xu, S. C. Zhang USTC/NSRL, Hefei, Anhui
	The key issues to obtain short beam bunch in storage ring is to lowering momentum compaction factor. When the linear momentum compaction factor is small, higher order momentum compaction factor can produce significant effects in the longitudinal beam dynamics. In the small storage ring, higher order momentum comaction factor is determined not only by sextupoles, and also by the fringe field of main magnets. In this paper, the higher order momentum factor formula including the effects of fringe field is deduced. As a example, the momentum compaction factor of HLS storage ring was calculated.
THPC045	Beam Uniformization System Using Multipole Magnets at the JAEA AVF Cyclotron	3077
	Y. Yuri, T. Agematsu, I. Ishibori, T. Ishizaka, H. Kashiwagi, S. Kurashima, N. Miyawaki, T. Nara, S. Okumura, K. Yoshida, T. Yuyama JAEA/ARTC, Takasaki
	It has been known that uniformization of a beam with a Gaussian profile is possible utilizing odd-order nonlinear forces. Here, we investigate uniformization of the transverse beam profile using nonlinear-focusing forces produced by multipole magnets in detail. We show that it is possible to uniformize an asymmetric beam as well as a Gaussian beam utilizing the odd and even-order nonlinear forces in combination. It enables us to perform high-uniformity irradiation at a constant particle fluence rate over the whole area of a large target. A research and development study of the beam uniformization system composed of sextupole and octupole magnets is now in progress at the JAEA AVF cyclotron facility. Some results of preliminary experiments on beam uniformization are also reported. P. F. Meads, Jr., IEEE Trans. Nucl. Sci. 30, 2838 (1983). **Y. Yuri et al., Phys. Rev. ST Accel. Beams 10, 104001 (2007).
THPC047	Studies of Losses During Continuous Transfer Extraction at the CERN proton Synchrotron	3083
	S. S. Gilardoni, J. Barranco CERN, Geneva
	Proton beams can be extracted from the CERN-PS at 14 GeV/c on five turns, using a technique called Continuous Transfer (CT). In this case, large losses due to particles scattered by an electrostatic septum used to slice the beam on five turns are observed in straight sections where the machine aperture is large enough to accommodate the circulating beam without any loss. These losses limit the maximum intensity deliverable to the SPS, like for the CERN to Gran Sasso (CNGS) neutrino program, because of the large irradiation of the site outside the PS tunnel and at the CERN fence. New simulation tools for a parametric study have been developed to improve the understanding of the observed loss pattern. A proposed solution to displace the losses in less critical section of the machine has been simulated and implemented in the CERN-PS. Simulations and experimental results of the loss study and reduction are presented.
THPC048	Study of Beam Losses at Transition Crossing at the CERN PS	3086
	S. S. Gilardoni, S. Aumon, M. Martini CERN, Geneva
	A series of studies has been carried out to understand and alleviate the beam losses in the CERN PS proton Synchrotron. In particular, losses appear at transition crossing during the pulsing of special quadrupoles used to create a gamma jump scheme and which causes a large optics and orbit distortion. After a brief summary of the gamma jump scheme at the PS, experimental and simulation results about the loss studies and reduction are presented.
THPC064	Use of LOCO at Synchrotron SOLEIL	3131
	L. S. Nadolski SOLEIL, Gif-sur-Yvette
	SOLEIL is a 354 m long 2.75 GeV third generation synchrotron light source delivering photons to beam-lines since January 2007. This paper will discuss in details the first attempts using LOCO code and problems encountered due to the storage ring lattice compactness. The introduction into the code of constraints on the quadrupole gradient variations gave tremendous improvements. The convergence is satisfactory, beta –beatings are reduced from 5% to below 1% RMS in both planes. Restoring the symmetry of the lattice enhanced the performances of the storage ring. In the last part, different ways of using LOCO as a powerful diagnostics tool will be given.
THPC077	Transportation Channel with Uniform Electron Distribution for the Kharkov Neutron Source based on Subcritical Assembly Driven with Linear Accelerator	3164
	A. Y. Zelinsky, I. M. Karnaukhov NSC/KIPT, Kharkov
	Electron beam transportation channel from linear accelerator to the neutron target of NSC KIPT neutron source should provide uniform distribution of electrons on target surface to prevent overheating of the target and reduce thermal stress. In the presented channel the method of uniform beam distribution formation with linear focusing elements and nonlinear focusing elements (octupole magnets) we used. Linear focusing elements were used to provide particle transportation through the channel without losses and to form required beam sizes at the target. Nonlinear focusing elements were used to modulate transverse velocity of peripheral particles. As a result the uniform electron beam of rectangular shape can be formed at the target. In the report the main principles of transportation channel design and results of calculations for NSC KIPT neutron source based on subcritical assembly driven by electron accelerator are presented. Lattice and parameters of focusing elements are presented. Calculation results show that proposed transportation channel lattice can provide uniform beam of rectangular shape with sizes 66x66 mm.
THPC129	Coupling Correction in NSLS X-ray Ring	3290
	M. G. Fedurin, I. Pinayev BNL, Upton, Long Island, New York
	In this paper we describe MATLAB script for reduction of the transverse coupling in the NSLS X-ray storage ring. The algorithm is based on varying strength of the skew quadrupoles and observation of the vertical beam size. The details of the iterative procedure are also discussed.
THPC135	Vertical Emittance Measurements and Optimisation at the Australian Synchrotron	3303
	M. J. Spencer, R. T. Dowd, G. LeBlanc ASP, Clayton, Victoria
	Adjustment to the vertical emittance of the Australian Synchrotron storage ring was made using 28 skew quadrupoles. The skew quadrupole settings were calculated using the LOCO method which uses measurements of vertical dispersion as well as transverse coupling. The vertical emittance was monitored indirectly through lifetime, tune crossing, x-ray pinhole camera and calibrated model calculations. The paper outlines the results of these studies.