First Name: M.
Middle Name:
Last Name: Cornacchia
Full Name: M. Cornacchia
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31 papers
| title: | Properties of the ultrashort gain length, self-amplified spontaneous emission free-electron laser in the linear regime and saturation |
| format: | journal article |
| year: | 2003 |
| 26 authors: | | | | | | | | | | | | | | | | | | | | | | | | | | |
| abstract: | VISA (Visible to Infrared SASE Amplifier) is a high-gain self-amplified spontaneous emission (SASE) free-electron laser (FEL), which achieved saturation at 840 nm within a single-pass 4-m undulator. The experiment was performed at the Accelerator Test Facility at BNL, using a high brightness 70-MeV electron beam. A gain length shorter than 18 cm has been obtained, yielding a total gain of 2x10(8) at saturation. The FEL performance, including the spectral, angular, and statistical properties of SASE radiation, has been characterized for different electron beam conditions. Results are compared to the three-dimensional SASE FEL theory and start-to-end numerical simulations of the entire injector, transport, and FEL systems. An agreement between simulations and experimental results has been obtained at an unprecedented level of detail. |
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| title: | Measurements of nonlinear harmonic radiation and harmonic microbunching in a visible SASE FEL |
| format: | conference procceeding |
| conference: | 24th International Free Electron Laser Conference |
| year: | 2003 |
| 13 authors: | | | | | | | | | | | | | |
| abstract: | The experimental characterization of nonlinear harmonic generation (NHG) and electron beam microbunching at saturation from a visible SASE FEL are presented in this report. The gain lengths, spectra and energies of NHG were experimentally measured up to the third harmonic, and agree with theoretical predictions. Electron beam microbunching in both the fundamental and the second harmonic as the function of the SASE output were experimentally observed over the full range of SASE gain. The bunching factors for both the fundamental (b(1)) and second harmonic (b(2)) were experimentally characterized at saturation. The microbunching data provides another test of SASE saturation as well as correlating the NHG and electron beam microbunching modes to the fundamental SASE. |
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| title: | Results of the VISA SASE FEL Experiment at 840 nm |
| format: | conference procceeding |
| conference: | 24th International Free Electron Laser Conference |
| year: | 2003 |
| 26 authors: | | | | | | | | | | | | | | | | | | | | | | | | | | |
| abstract: | VISA (Visible to Infrared SASE Amplifier) is a high-gain self-amplified spontaneous emission (SASE) free-electron laser (FEL), which achieved saturation at 840 nm within a single-pass 4-m undulator. A gain length shorter than 18 cm has been obtained, yielding the gain of 2x10(8) at saturation. The FEL performance, including the spectral, angular, and statistical properties of SASE radiation, has been characterized for different electron beam conditions. The results are compared to 3-D SASE FEL theory and start-to-end numerical simulations of the entire injector, transport, and FEL system. Detailed agreement between simulations and experimental results is obtained over the wide range of the electron beam parameters. |
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| title: | Fundamental and harmonic microbunching in a high-gain self-amplified spontaneous-emission free-electron laser |
| format: | unknown |
| year: | 2002 |
| 13 authors: | | | | | | | | | | | | | |
| abstract: | Electron beam microbunching in both the fundamental and second harmonic in a high-gain self-amplified spontaneous emission free-electron laser (SASE FEL) was experimentally characterized using coherent transition radiation. The microbunching factors for both modes (b1 and b2) approach unity, an indication of FEL saturation. These measurements are compared to the predictions of FEL simulations. The simultaneous capture of the microbunching and SASE radiation for individual micropulses correlate the longitudinal electron beam structure with the FEL gain. |
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| title: | Experimental characterization of nonlinear harmonic radiation from a visible self-amplified spontaneous emission free-electron laser at saturation |
| format: | unknown |
| year: | 2002 |
| 12 authors: | | | | | | | | | | | | |
| abstract: | Nonlinear harmonic radiation was observed using the VISA self-amplified, spontaneous emission (SASE) free-electron laser (FEL) at saturation. The gain lengths, spectra, and energies of the three lowest SASE FEL modes were experimentally characterized. The measured nonlinear harmonic gain lengths and center spectral wavelengths decrease with harmonic number, n, which is consistent with nonlinear harmonic theory. Both the second and third nonlinear harmonics energies are about 1% of the fundamental energy. These experimental results demonstrate for the first time the feasibility of using nonlinear harmonic SASE FEL radiation to produce coherent, femtosecond X-rays. (33 References). |
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| title: | Fundamental and Harmonic Microbunching Measurements in a High-Gain, Self-Amplified, Spontaneous Emission Free-Electron Laser |
| format: | preprint |
| year: | 2002 |
| 13 authors: | | | | | | | | | | | | | |
| abstract: | The self-amplified, spontaneous emission free-electron laser (SASE-FEL) gain process is a collective instability which induces microbunching in the electron beam. Micro-bunching approaching unity at the fundamental FEL wavelength (845 nm), and its second harmonic, have been measured at the VISA FEL, at or near saturation. These measurements, which use the beam's coherent transition radiation (CTR) spectrum, are sompared to the predictions of FEL simulations. Comparison of shot-by-shot SASE and CTR signals firmly establishes the role of SASE in the development of microbunching harmonics. |
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| title: | Properties of an Ultra-Short Gain Length, Saturated, Self-Amplified Spontaneous Emission FEL |
| format: | preprint |
| year: | 2002 |
| 26 authors: | | | | | | | | | | | | | | | | | | | | | | | | | | |
| abstract: | The VISA experiment, conducted at the BNL Accelerator Test Facility (ATF), has studied the properties of SASE FEL process in a saturating system. The experiment utilized a high brightness electron beam and a strong focusing undulator. Saturated gain greater than 108, with a power gain length below 18 cm, was obtained at 840 nm. Measurements of FEL gain, spectral and angular properties of SASE radiation are reported, and the results are compared to theory and to start-to-end simulations of the system. FEL performance was found critically dependent on the compression of the electron beam. |
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| title: | Characterization of an 800 nm SASE FEL at saturation |
| format: | conference procceeding |
| conference: | 23rd International Free Electron Laser Conference |
| year: | 2002 |
| 24 authors: | | | | | | | | | | | | | | | | | | | | | | | | |
| abstract: | Visible to Infrared SASE Amplifier is a free electron laser (FEL) designed to saturate at a radiation wavelength of 800 nm within a 4 m long, strong focusing undulator. A large gain is achieved by driving the FEL with 72 MeV, high brightness beam of BNL's accelerator test facility. We present measurements that demonstrate saturation in addition to the frequency spectrum of the FEL radiation. Energy, gain length and spectral characteristics are compared and shown to agree with simulation and theoretical predictions. (16 References). |
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| title: | Visible-infrared self-amplified spontaneous emission amplifier free electron laser undulator |
| format: | unknown |
| year: | 2001 |
| 17 authors: | | | | | | | | | | | | | | | | | |
| abstract: | The visible-infrared self-amplified spontaneous emission amplifier (VISA) free electron laser (FEL) is an experimental device designed to show self-amplified spontaneous emission (SASE) to saturation in the near infrared to visible light energy range. It generates a resonant wavelength output from 800?600 nm, so that silicon detectors may be used to characterize the optical properties of the FEL radiation. VISA is designed to show how SASE FEL theory corresponds with experiment in this wavelength range, using an electron beam with emittance close to that planned for the future Linear Coherent Light Source at SLAC. VISA comprises a 4 m pure permanent magnet undulator with four 99 cm segments, each of 55 periods, 18 mm long. The undulator has distributed focusing built into it, to reduce the average beta function of the 70?85 MeV electron beam to about 30 cm. There are four FODO cells per segment. The permanent magnet focusing lattice consists of blocks mounted on either side of the electron beam, in the undulator gap. The most important undulator error parameter for a free electron laser is the trajectory walk-off, or lack of overlap of the photon and electron beams. Using pulsed wire magnet measurements and magnet shimming, we were able to control trajectory walk-off to less than |
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| title: | Measuring FEL radiation properties at VISA-FEL |
| format: | conference procceeding |
| conference: | 2001 Particle Accelerator Conference |
| year: | 2001 |
| 25 authors: | | | | | | | | | | | | | | | | | | | | | | | | | |
| abstract: | The VISA (Visible to Infrared SASE Amplifier) SASE free electron laser has been successfully operated at the Accelerator Test Facility (ATF) at BNL. High gain and saturation were observed at 840 nm. We describe here the diagnostic system, experimental procedures and data reduction algorithms, as the FEL performance was measured along the length of the undulator. We also discuss selected spectral radiation measurements. (10 References). |
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| title: | Initial gain measurements of an 800 nm SASE FEL, VISA |
| format: | conference procceeding |
| conference: | 22nd International Free Electron Laser Conference |
| year: | 2001 |
| 26 authors: | | | | | | | | | | | | | | | | | | | | | | | | | | |
| abstract: | The visible to infrared SASE amplifier (VISA) FEL is designed to obtain high gain at a radiation wavelength of 800 nm. The FEL uses the high brightness electron beam of the accelerator test facility (ATF), with energy of 72 MeV. VISA uses a novel, 4 m long, strong focusing undulator with a gap of 6 mm and a period of 1.8 cm. To obtain large gain the beam and undulator axis have to be aligned to better than 5 mu m. Results from initial measurements on the alignment, gain, and spectrum will be presented and compared to theoretical calculations and simulations. (10 References). |
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| title: | Status and initial commissioning of a high gain 800 nm SASE FEL |
| format: | conference procceeding |
| conference: | 21st International Free Electron Laser Conference |
| year: | 2000 |
| 22 authors: | | | | | | | | | | | | | | | | | | | | | | |
| abstract: | We describe the status and initial commissioning of the visible to infrared SASE amplifier (VISA) experiment. VISA uses a strong focusing 4 m undulator, the Brookhaven National Laboratory ATF linac with an energy of 72 MeV, and a photoinjector electron source. The VISA fundamental radiation wavelength is near 800 nm and the power expected at saturation is near 60 MW. Power, angular and spectral measurements are planned for the VISA radiation and these results will be analyzed and compared with SASE FEL theory and computer simulation. In addition, the induced electron beam micro-bunching will be measured using coherent transition radiation. (12 References). |
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| title: | Photon beam diagnostics for VISA FEL |
| format: | conference procceeding |
| conference: | 1999 Particle Accelerator Conference |
| year: | 1999 |
| 17 authors: | | | | | | | | | | | | | | | | | |
| abstract: | The VISA (Visible to Infrared SASE Amplifier) project is designed to be a SASE-FEL driven to saturation in the sub-micron wavelength region. Its goal is to test various aspects of the existing theory of self-amplified spontaneous emission, as well as numerical codes. Measurements include: angular and spectral distribution of the FEL light at the exit and inside of the undulator; electron beam micro-bunching using CTR; single-shot time resolved measurements of the pulse profile, using an auto-correlation technique and FROG algorithm. The diagnostics are designed to provide maximum information on the physics of the SASE-FEL process, to ensure a close comparison of the experimental results with theory and simulations. (9 References). |
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| title: | The VISA FEL Undulator |
| format: | conference procceeding |
| conference: | 20th International Free Electron Laser Conference |
| year: | 1999 |
| 14 authors: | | | | | | | | | | | | | | |
| abstract: | The Visible-Infrared SASE Amplifier (VISA) FEL is an experimental device designed to show self amplified spontaneous emission (SASE) to saturation in the 800-600 nm range, where silicon detectors may be used to characterize the optical properties of the FEL radiation. VISA is the first SASE FEL designed to saturate, and its diagnostics will provide important checks of theory. |
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| title: | Experimental non linear beam dynamics studies with a turn-by-turn phase space monitor at SPEAR |
| format: | conference procceeding |
| conference: | ICFA Workshop on Nonlinear and Collective Phenomena in Beam Physics |
| year: | 1999 |
| 3 authors: | | | |
| abstract: | About 10 years ago the possibility of using turn-by-turn phase beam position monitors to gain insight into phase space dynamics of a single particle in a storage ring raised some interest among accelerator physicists. It was soon argued that Landau damping and collective effects would seriously complicate the interpretation of data. We have established that in SPEAR it is possible to lock a single bunch into a collective 'rigid body' mode. When in this mode the bunch will behave similar to a super particle of finite size with the charge equal to that of the bunch. In this paper we report on experiments that demonstrate this effect. We also numerically study the strong coupling limit, in which the transition to 'rigid body' motion occurs, for the two models proposed earlier. We present the experiments on non-linear resonance crossing and frequency map measurement in the 'super particle' framework. (11 References). |
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| title: | Observations, Measurements and Applications of a Steady Collective Mode in an Electron Storage Ring |
| format: | preprint |
| year: | 1998 |
| 3 authors: | | | |
| abstract: | A single bunch of charged particles in a storage ring is a system of 10(9) - 10(11) coupled non-linear oscillators with radiative energy loss and compensated by the accelerating cavity. A stable collective mode in such system was induced and observed in SPEAR storage rign using a turn-by-turn phase space monitor. New possibilities of using this mode as a tool to experimentally study non-linear dynamics in storage rings are discussed. |
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| title: | Experimental nonlinear beam dynamics studies at SPEAR |
| format: | conference procceeding |
| conference: | 1997 Particle Accelerator Conference |
| year: | 1998 |
| 5 authors: | | | | | |
| abstract: | The frequency map analysis of a Hamiltonian system recently introduced to accelerators physics in combination with turn-by-turn phase space measurements opens new experimental opportunities for studying nonlinear dynamic in storage rings. In this paper we report on the experimental program at SPEAR having the goal of measuring the frequency map of the machine. In this paper we discuss the accuracy of the instantaneous tune extraction from experimental data and demonstrate the possibility of frequency map measurement. (7 References). |
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| title: | Measurement of the variation of machine parameters and the effect of the power supplies ripple on the instantaneous tunes at SPEAR |
| format: | conference procceeding |
| conference: | 1997 Particle Accelerator Conference |
| year: | 1998 |
| 5 authors: | | | | | |
| abstract: | For long term stability analysis, time variation of tunes is important. We have proposed and tested a technique for measuring the magnitude of this variation. This was made possible by using tune extraction algorithms that require small number of turns thus giving an instantaneous tune of the machine. In this paper we demonstrate the measured effect of the tune modulation with 60 Hz power supplies ripple, power line interference from the SLAC linac operating at 30 Hz repetition rate, and non-periodic variation. (8 References). |
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| title: | Measurements of the tune variations induced by non-linearities in lepton machines |
| format: | conference procceeding |
| conference: | 1996 European Particle Accelerator Conference |
| year: | 1997 |
| 9 authors: | | | | | | | | | |
| abstract: | The precise measurement of the betatron tune as a function of the oscillation amplitude provides a useful information on non-linear beam dynamics. In lepton accelerators, this measurement is made difficult due to various damping mechanism. To counteract this, we propose to use algorithms that provide a precise measurement of the tune in a small number of turns. We apply these procedures in LEP at injection and collision energy, as well as in SPEAR at injection energy. Collections of experimental data, and a first comparison with the results of model-based simulations are discussed. (9 References). |
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| title: | Research and development toward a 4.5-1.5 angstrom linac coherent light source (LCLS) at SLAC |
| format: | conference procceeding |
| conference: | 17th International Free Electron Laser Conference |
| year: | 1996 |
| 32 authors: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| abstract: | In recent years significant studies have been initiated on the feasibility of utilizing a portion of the 3 km S-band accelerator at SLAC to drive a short wavelength (4.5-1.5 Angstrom) Linac Coherent Light Source (LCLS), a Free-Electron Laser (FEL) operating in the Self-Amplified Spontaneous Emission (SASE) regime. Electron beam requirements for single-pass saturation in a minimal time include: 1) a peak current in the 7 kA range, 2) a relative energy spread of <0.05%, add 3) a transverse emittance, epsilon [rad-m], approximating the diffraction-limit condition epsilon=lambda/4 pi, where lambda[m] is the output wavelength. Requirements on the insertion device include field error levels of 0.02% for keeping the electron bunch centered on and in phase with the amplified photons, and a focusing beta of 8 m/rad for inhibiting the dilution of its transverse density. Although much progress has been made in developing individual components and beam-processing techniques necessary for LCLS operation down to similar to 20 Angstrom, a substantial amount of research and development is still required in a number of theoretical and experimental areas leading to the construction and operation of a 4.5-1.5 Angstrom LCLS. In this paper we report on a research and development program underway and in planning at SLAC for addressing critical questions in these areas. These include the construction and operation of a linac test stand for developing laser-driven photocathode rf guns with normalized emittances approaching 1 mm-mrad; development of advanced beam compression, stability, and emittance control techniques at multi-GeV energies; the construction and operation of a FEL Amplifier Test Experiment (FATE) for theoretical and experimental studies of SASE at IR wavelengths; an undulator development program to investigate superconducting, hybrid/permanent magnet (hybrid/PM), and pulsed-Cu technologies; theoretical and computational studies of high-gain FEL physics and LCLS component designs; development of X-ray optics and instrumentation for extracting, modulating, and delivering photons to experimental users; and the study and development of scientific experiments made possible by the source properties of the LCLS. |
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| title: | Measurements of the octupole-induced amplitude-dependent frequency shift in SPEAR |
| format: | conference procceeding |
| conference: | 1995 Particle Accelerator Conference |
| year: | 1995 |
| 5 authors: | | | | | |
| abstract: | Four octupoles are used in SPEAR to provide the frequency spread for Landau damping of coupled-bunch motions at high current. With the planned implementation of a new low-emittance lattice, the effectiveness of the octupoles needs to be quantified. The recent development of a multi-dimensional turn-by-turn phase-space monitor and the availability of an accurate frequency analysis technique have made measurement of the octupole-induced amplitude-dependent frequency shift in the new SPEAR lattice possible. This paper presents the data collection and analysis procedures, and compares experimental results to model-based simulations. (5 References). |
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| title: | Nonlinear beam dynamics experimental program at SPEAR |
| format: | conference procceeding |
| conference: | Workshop on Nonlinear Dynamics in Particle Accelerators: Theory and Experiments |
| year: | 1995 |
| 5 authors: | | | | | |
| abstract: | Since nonlinear effects can impose strict performance limitations on modern colliders and storage rings, future performance improvements depend on further understanding of nonlinear beam dynamics. Experimental studies of nonlinear beam motion in three-dimensional space have begun in SPEAR using turn-by-turn transverse and longitudinal phase-space monitors. This paper presents preliminary results from an on-going experiment in SPEAR. (10 References). |
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| title: | Status of the variable momentum compaction storage ring experiment in SPEAR |
| format: | conference procceeding |
| conference: | 1993 Particle Accelerator Conference |
| year: | 1993 |
| 11 authors: | | | | | | | | | | | |
| abstract: | Variable momentum compaction lattices have been proposed for electron-positron colliders and synchrotron radiation sources to control synchrotron tune and bunch length. To address questions of single particle stability limits, a study has been initiated to change the SPEAR lattice into a variable momentum compaction configuration for experimental investigation of the beam dynamics. In this paper, we describe a model-based method used to transform SPEAR from the injection lattice to the low momentum compaction configuration. Experimental observations of the process are reviewed. (12 References). |
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| title: | A high luminosity superconducting mini collider for phi meson production and particle beam physics |
| format: | conference procceeding |
| conference: | 1991 Particle Accelerator Conference |
| year: | 1991 |
| 14 authors: | | | | | | | | | | | | | | |
| abstract: | A 510-MeV electron-positron collider has been proposed at the University of California at Los Angeles to study particle beam physics and phi-meson physics at luminosities larger than 1032 cm/sup -2/s/sup -1/. The collider consists of a single compact superconducting storage ring (SMC), with a bending field of 4 T and a current larger than 1 A. A discussion is presented of the main characteristics of this system and its major technical components: superconducting dipoles and the RF vacuum and injection systems. (6 References). |
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| title: | Conceptual Design of a High Luminosity 510 MeV Collider |
| format: | conference procceeding |
| conference: | 1991 Particle Accelerator Conference |
| year: | 1991 |
| 3 authors: | | | |
| abstract: | We discuss the magnetic lattice design of a high luminosity 510 MeV electron-positron collider, based on high field superconduction bending dipoles. The design criteria are flexibility in the choice of the tune and beta functions at the interaction point, horizontal emittance larger than 1 mm mrad to produce a luminosity larger than 10(32) cm(-2)s(-1), large synchrotron radiation damping rate, and large momentum compaction. The RF system parameter are chosen to provide a short bunch length also when the beam energy spread is determined by the microwave instability. A satisfactory ring dynamic aperture, and a simultaneous small value of the horizontal and vertical beta function at the interaction point, we expect will be achieved by using Cornacchia Halbach modified sextupoles. |
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| title: | The Trieste synchrotron radiation project |
| format: | conference procceeding |
| conference: | 5th National Conference on Synchrotron Radiation Instrumentation |
| year: | 1988 |
| 7 authors: | | | | | | | |
| abstract: | The present the project for a superhigh brilliance soft X-ray source at Trieste. At present the project is fully funded and the conceptual design is being developed. The facility, scheduled to become operational in 1992, will deliver unprecedented levels of brilliance, and will be used for a variety of experiments in physics, chemistry, materials science, engineering, biology, technology, and medical research, involving scientists from Italy, from a number of European countries, and from the USA. (2 References). |
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| title: | Feasibility study of a storage ring for a high-power XUV free-electron laser |
| format: | journal article |
| year: | 1986 |
| 12 authors: | | | | | | | | | | | | |
| abstract: | A high-gain free-electron lase (FEL), operating in a special by-pass of a storage ring, can provide tens of megawatts of coherent power at wavelengths shorter than 1000 AA. The requirements on beam quality are demanding-a few hundred amperes of peak current in an emittance of about 10/sup -8/ m-rad with a relative energy spread of about 10/sup -3/. Designing an electron storage ring with the required characteristics involves a comprehensive analysis of the restrictions arising from, and relationships between, the FEL physics, the multiparticle beam phenomena, and the ring lattice structure. A summary of such a study is reported and some design examples are given. (39 References). |
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| title: | Design concepts of a storage ring for a high power XUV free electron laser |
| format: | conference procceeding |
| conference: | 7th International Free Electron Laser Conference |
| year: | 1986 |
| 12 authors: | | | | | | | | | | | | |
| abstract: | The authors report on the study of a storage ring capable of sustaining an electron beam of the quality required for a high-gain free electron laser in the vacuum ultraviolet and X-ray region. They describe a method for the optimization of the design of the storage ring where several competing and often conflicting requirements come into play. They present an example design of a ring that satisfies the required conditions of beam quality and is able to produce coherent radiation at 400 AA with tens of megawatts of peak power. (11 References). |
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| title: | Optimization of the parameters of a storage ring for a high power XUV free electron laser |
| format: | conference procceeding |
| conference: | International Conference on Insertion Devices for Synchrotron Sources |
| year: | 1986 |
| 12 authors: | | | | | | | | | | | | |
| abstract: | The authors describe the operation of an XUV high gain FEL operating within a bypass of an electron storage ring, and discuss the implications on storage ring optimization imposed be FEL requirements. It transpires that, in the parameter regime of interest, collective effects within the beam play an important role. For example, intrabeam scattering dilutes the transverse emittance of the beam and the microwave instability increases the momentum spread. Both phenomena reduce the effectiveness of the FEL. A computer code, ZAP, has been written which, for a given lattice design, takes all such effects into consideration and produces a figure of merit for FEL operation for that machine. They show the results of ZAP for several storage ring designs, all optimized for FEL operation, and present a design example of a facility capable of producing coherent radiation at 400 AA with tens of megawatts of peak power. (24 References). |
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| title: | Storage ring design for a short wavelength FEL |
| format: | conference procceeding |
| conference: | 1985 Particle Accelerator Conference |
| year: | 1985 |
| 12 authors: | | | | | | | | | | | | |
| abstract: | A high gain free electron laser (FEL) operating in a special bypass of a storage ring can provide tens of megawatts of coherent power at wavelengths shorter than 1000 AA. The requirements on beam qualities are demanding, a few hundred amperes of peak current in an emittance of about 10/sup -8/ m-rad with a relative energy spread of approximately 10/sup -3/. Designing an electron storage ring with the required characteristics involves a comprehensive analysis of the restrictions from, and relationships between, the FEL physics, the multiparticle beam phenomena, and the ring lattice structure. A summary of such a study is reported and some design examples are given. (12 References). |
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| title: | A study on the conditions required for the transverse stability of a coasting beam in proton storage rings |
| format: | unknown |
| year: | 1982 |
| 2 authors: | | |
| abstract: | A theory is developed that allows calculation of the threshold current of a coasting beam in a circular accelerator or storage ring for an arbitrary frequency versus momentum curve. This theory is applied to the simple case of a parabolic term in the curve, for which an analytical solution of the stability problem is obtained. The general case of an arbitrary frequency distribution is then solved numerically, and the solution used to study the stability of a coasting beam in a high-energy proton storage ring like ISABELLE during the stacking process and for a full-intensity beam. This is done for different momentum distribution curves and includes the effect of the nonlinear space-charge term and of up to sixteen independent magnetic multipoles. The algorithm allows calculation of both the number and the strength of the magnetic multipoles needed to provide a stable beam of the desired current. (8 References). |
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