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PROGRESSREPORTONBEAMBREAK-UPATSLAC* BY

by E. V. Farinholt, R. H. Helm, H. A. Hogg, R. F. Koontz, G. A. Loew, R. H. Miller , 1967
"... The purpose of this paper is to review the progress that has been made in the last six months in understanding and remedying the beam break-up effect (BBU) at SLAC. No attempt will be made to give a comprehensive summary of earlier ..."
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The purpose of this paper is to review the progress that has been made in the last six months in understanding and remedying the beam break-up effect (BBU) at SLAC. No attempt will be made to give a comprehensive summary of earlier

Brain magnetic resonance imaging with contrast dependent on blood oxygenation.

by S Ogawa , T M Lee , A R Kay , D W Tank - Proc. Natl. Acad. Sci. USA , 1990
"... ABSTRACT Paramagnetic deoxyhemoglobin in venous blood is a naturally occurring contrast agent for magnetic resonance imaging (MRI). By accentuating the effects of this agent through the use of gradient-echo techniques in high fields, we demonstrate in vivo images of brain microvasculature with imag ..."
Abstract - Cited by 648 (1 self) - Add to MetaCart
ABSTRACT Paramagnetic deoxyhemoglobin in venous blood is a naturally occurring contrast agent for magnetic resonance imaging (MRI). By accentuating the effects of this agent through the use of gradient-echo techniques in high fields, we demonstrate in vivo images of brain microvasculature

Analytical Formula for Weak Multi-Bunch Beam Break-Up in a Linac ∗

by Karl L. F. Bane, Zenghai Li, Karl L. F. Bane, Zenghai Li , 2000
"... In designing linac structures for multi-bunch applications we are often interested in estimating the effect of relatively weak multi-bunch beam breakup (BBU), due to the somewhat complicated wakefields of detuned structures. This, for example, is the case for the injector linacs of the JLC/NLC linea ..."
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/NLC linear collider project (see Ref. [1]). Deriving an analytical formula for such a problem is the subject of this report. Note that the more studied multibunch BBU problem, i.e. the effect on a bunch train of a single strong mode, the so-called “cumulative beam break-up instability ” (see, e.g. Ref. [2

SELF-CONSISTENT TRANSVERSE DYNAMICS AND INTERBUNCH ENERGY EXCHANGE IN DIELECTRIC LOADED WAKEFIELD ACCELERATING STRUCTURES *

by unknown authors
"... The self-consistent transverse dynamics of high current relativistic electron beams used for generating wake fields in dielectric loaded structures is investigated. The primary application of this work is to multi-bunch wakefield acceleration. The maximum distance the high current beam can travel th ..."
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through the structure in the absence of focusing has been simulated. The BBU (beam break-up) effects and interbunch energy transfer within accelerated electron bunch have been studied as well. We consider ramped charge distribution in the sequence of high current drive bunch. This ramped drive charge

SLAC-PUB-13174 MICROBUNCHING AND BEAM BREAK-UP IN DUV-FEL ACCELERATOR

by T. Shaftan, H. Loos, B. Sheehy, L. Carr, Z. Huang C. Limborg
"... We present the results of electron beam longitudinal modulation studies in the DUV-FEL accelerator. For bunch length determination we used the “zero-phasing” method, based on a measurement of the chirped electron bunch energy spectra. The measurements revealed a spiky structure in the longitudinal p ..."
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phase space [1]. A model based on space charge effect is considered [2] to explain of the obtained phenomena. The analysis of the energy spectra has shown a sensitivity of the structure to the electron beam peak current, energy and longitudinal non-uniformity of the RF gun drive laser. Analytical

Influence of the Break-up on the Fusion and Scattering Processes

by J Lubian , P R S Gomes , R M Anjos , I Padron , C Muri , S B Moraes , J J S Alves , A M M Maciel , R Liguori Neto , N Added , G V Martí , M Ramírez , A J Pacheco , O A Capurro , J O Fernández Niello , J E Testoni , D Abriola , M R Spinella
"... We present results of the study of the influence of the break-up process on the fusion, scattering and reaction cross sections, at near barrier energies. Most of the discussed reactions and scattering mechanisms are induced by the stable weakly bound nuclei 6,7 Li and 9 Be, although comparisons wit ..."
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with reactions induced by strongly bound nuclei are also made. We give a picture of the break-up and fusion mechanisms at energies above the Coulomb barrier. The effects of the coupling of elastic, inelastic and transfer channels on the fusion cross section, at energies close to and bellow the Coulomb barrier

BEAM BREAK-UP EXPERIMENTS AT SLAC ’

by H. Altenmueller, E. V. Farinholt, Z. D. Farkas, W. B. Herrmannsfeldt, H. A. Hogg, R. F. Koontz, C. J. Kruse, G. A. Loew, R. H. Miller , 1966
"... The first observation of beam break-up at SLAC was made on April 27, 1966, one week after the beam was first turned on over two-thirds of the accelerator’s two-mile length. I The event caused more astonishment ..."
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The first observation of beam break-up at SLAC was made on April 27, 1966, one week after the beam was first turned on over two-thirds of the accelerator’s two-mile length. I The event caused more astonishment

A third-generation wave model for coastal regions, 1, Model description and validation

by R. C. Ris, L. H. Holthuijsen, N. Booij
"... Abstract. A third-generation spectral wave model (Simulating Waves Nearshore (SWAN)) for small-scale, coastal regions with shallow water, (barrier) islands, tidal flats, local wind, and ambient currents is verified in stationary mode with measurements in five real field cases. These verification cas ..."
Abstract - Cited by 311 (0 self) - Add to MetaCart
local wind. The wave fields were highly variable with up to 3 orders of magnitude difference in energy scale in individual cases. The model accounts for shoaling, refraction, generation by wind, whitecapping, triad and quadruplet wave-wave interactions, and bottom and depth-induced wave breaking

Nuclear break-up of 11 Be

by unknown authors , 709
"... The break-up of 11 Be was studied at 41 AMeV using a secondary beam of 11 Be from the GANIL facility on a 48 Ti target by measuring correlations between the 10 Be core, the emitted neutrons and gamma rays. The nuclear break-up leading to the emission of a neutron at large angle in the laboratory fra ..."
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The break-up of 11 Be was studied at 41 AMeV using a secondary beam of 11 Be from the GANIL facility on a 48 Ti target by measuring correlations between the 10 Be core, the emitted neutrons and gamma rays. The nuclear break-up leading to the emission of a neutron at large angle in the laboratory

DISPERSION IN THE PRESENCE OF STRONG TRANSVERSE WAKEFIELDS

by Ralph W. Assmann, Alex Chao
"... To minimize emittance growth in a long linac, it is necessary to control the wakefields by correcting the beam orbit excursions. In addition, the particle energy is made to vary along the length of the bunch to introduce a damping, known as the BNS damping, to the beam break-up effect. In this paper ..."
Abstract - Cited by 1 (0 self) - Add to MetaCart
To minimize emittance growth in a long linac, it is necessary to control the wakefields by correcting the beam orbit excursions. In addition, the particle energy is made to vary along the length of the bunch to introduce a damping, known as the BNS damping, to the beam break-up effect
Results 1 - 10 of 15,581