| Paper | Title | Page |
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| WPAP013 | Magnesium Film Photocathodes for High Brilliance Electron Injectors | 1350 |
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| Advanced high brilliance electron injectors require photocathodes having low thermal emittance, high quantum efficiency (QE) and prompt response. They should be easy to handle and capable of working in the very high electric fileds of a RF gun. Magnesium films deposited by laser ablation and sputtering techniques are discussed and QE measurements are presented. | ||
| MOPB008 | Temporal E-Beam Shaping in an S-Band Accelerator | 642 |
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Funding: This work was supported by U.S. Department of Energy, Office of Basic Energy Sciences, under Contracts DE-AC02-98CH10886 and DE-AC03-76SF00515. New short-wavelength SASE light sources will require very bright electron beams, brighter in some cases than is now possible. One method for improving brightness involves the careful shaping of the electron bunch to control the degrading effects of its space charge forces. We study this experimentally in an S-band system, by using an acousto-optical programmable dispersive filter to shape the photocathode laser pulse that drives the RF photoinjector. We report on the efficacy of shaping from the IR through the UV, and the effects of shaping on the electron beam dynamics. |
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| TPAE002 | The Project PLASMONX for Plasma Acceleration Experiments and a Thomson X-Ray Source at SPARC | 820 |
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| We present the status of the activity on the project PLASMONX, which foresees the installation of a multi-TW Ti:Sa laser system at the CNR-ILIL laboratory to conduct plasma acceleration experiments and the construction of an additional beam line at SPARC to develop a Thomson X-ray source at INFN-LNF. After pursuing self-injection experiments at ILIL, when the electron beam at SPARC will be available the SPARC laser system will be upgraded to TW power level in order to conduct either external injection plasma acceleration experiments and ultra-bright X-ray pulse generation with the Thomson source. Results of numerical simulations modeling the interaction of the SPARC electron beam and the counter-propagating laser beam are presented with detailed discussion of the monochromatic X-ray beam spectra generated by Compton backscattering: X-ray energies are tunable in the range 20 to 1000 keV, with pulse duration from 30 fs to 20 ps. Preliminary simulations of plasma acceleration with self-injection are illustrated, as well as external injection of the SPARC electron beam. The proposed time schedule for this initiative is finally shown, which is tightly correlated with the progress of the SPARC project. | ||
| RPPT013 | Status of the SPARC Project | 1327 |
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| The SPARC project has entered its installation phase at INFN-LNF: its main goal is the promotion of an R&D activity oriented to the development of a high brightness photoinjector to drive SASE-FEL experiments. The design of the 150 MeV photoinjector has been completed and the construction of its main components is in progress, as well as the design of the 12 m undulator. In this paper we will report on the installation and test of some major components, like the Ti:Sa laser system to drive the photo-cathode, the RF gun, the RF power system, as well as some test results on the RF deflector and 4th harmonic X-band cavity prototypes. Advancements in the control and beam diagnostics systems will also be reported, in particular on the emittance-meter device for beam emittance measurements in the drift space downstream the RF gun. Recent results on laser pulse shaping, obtained with two alternative techniques (DAZZLER and Liquid Crystal Mask), show the feasibility of producing 10 ps flat-top laser pulses in the UV with rise time below 1 ps, as needed to maximize the achievable beam brightness. First FEL experiments have been proposed, using SASE, seeding and non-linear resonant harmonics: these will be briefly described. | ||
| RPPT031 | Recent Results from and Future Plans for the VISA II SASE FEL | 2167 |
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| As the promise of X-ray Free Electron Lasers (FEL) comes close to realization, the creation and diagnosis of ultra-short pulses is of great relevance in the SASE FEL (Self-Amplified Spontaneous Emission) community. The VISA II (Visible to Infrared SASE Amplifier) experiment entails the use of a chirped electron beam to drive a high gain SASE FEL at the Accelerator Test Facility (ATF) in Brookhaven National Labs (BNL). The resulting ultra-short pulses will be diagnosed using an advanced FROG (Frequency Resolved Optical Gating) technique, as well as a double differential spectrum (angle/wavelength) diagnostic. Implementation of sextupole corrections to the longitudinal aberrations affecting the high energy-spread chirped beam during transport to the VISA undulator is studied. Start-to-end simulations, including radiation diagnostics, are discussed. Initial experimental results involving a highly chirped beam transported without sextupole correction, the resulting high gain lasing, and computational analysis are briefly reported. |