| Paper | Title | Page |
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| TUPMN035 | Generation of a Multipulse Comb Beam and a Relative Twin Pulse FEL | 989 |
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| A radiofrequency electron gun joined to a compressor generates trains of THz subpicosecond electron pulses. Assuming a prompt electron emission, the laser train generates a train of electron disks at the cathode, then the disk train evolves towards a slug with a slight density modulation but also with a peculiar sawtooth energy modulation. This kind of energy modulation is transformed into a density modulation by a velocity bunching compressor recovering at a good extent the initial intensity beam profile. We study here through simulations the process looking to its characteristics as function peak and frequency characteristics of the laser and the parameters of the accelerator. | ||
| TUPMN039 | Status of the SPARC-X Project | 1001 |
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| SPARC-X is a two branch project consisting in the SPARC test facility dedicated to the development and test of critical subsystems such as high brightness photoinjector and a modular expandable undulator for SASE-FEL experiments at 500 nm with seeding, and the SPARX facility aiming at generation of high brightness coherent radiation in the 3-13 nm range, based on the achieved expertise. The projects are supported by MIUR (Research Department of Italian Government) and Regione Lazio. SPARC has completed the commissioning phase of the photoinjector in November 2006. The achieved experimental results are here summarized together with the status of the second phase commissioning plans. The SPARX project is based on the generation of ultrahigh peak brightness electron beams at the energy of 1 and 2 GeV generating radiation in the 3-13 nm range. The construction is at the moment planned in two steps starting with a 1 GeV Linac. The project layout including both RF-compression and magnetic chicane techniques has been studied and compared, together with the feasibility of a mixed s-band and x-band linac option. | ||
| TUPMN041 | Three Dimensional Analysis of the X-Radiation Produced by a Collective Thomson Source | 1007 |
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| A set of 3-D equations that describes the collective head to head interaction between a laser pulse and a relativistic electron beam is presented and solved. The relevant dispersion relation is studied, as well as the gain properties of the system. The FEL instability dominates the radiation process. The radiation emitted is characterized by short wavelength, thin spectrum and high coherence. The most important three-dimensional effects are the emittance of the beam and the transverse distribution of the laser energy. The production of radiation wavelengths of 12 nm, 1nm, and 1 Angstron are presented. | ||
| THPAN031 | Optimization of the Beam Line Characteristics by Means of a Genetic Algorithm | 3295 |
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| The optimization of the optics in a LINAC requires a very demanding tuning of the involved parameters, particularly in the case of high brightness electron beams applied to the production of X-ray in a Thomson back-scattering source. The relationship between the parameters is non-linear and it is not possible to treat them as independent variables, causing the impossibility of setting them handily. A genetic algorithm is a powerful tool able to circumvent this difficulty. We have applied the genetic algorithm to the case of the SPARC beam line. | ||
| THPAN032 | Study of the Beam Dynamics in a Linac with the Code RETAR | 3298 |
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| The three-dimensional fully relativistic and self-consistent code RETAR has been applied to model the dynamics of high-brightness electron beams and in particular to assess the importance of the retarded radiative part of the emitted electromagnetic fields in all conditions where the electrons experience strong accelerations. In this analysis we evaluate the radiative energy losses in the electron emission process from the photocathode of an injector, during the successive acceleration of the electron beam in the RF cavity and the focalization due to the magnetic field of the solenoid, taking also into account the e.m. field of the laser illuminating the cathode and the inhomogeneities on the cathode surface. The analysis is specifically carried out with parameters of importance in the framework of the SPARC and PLASMONX projects. |