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P. Pierini

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Last Name: Pierini

Full Name: P. Pierini

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11 papers
title: First Observation of Self-Amplified Spontaneous Emission in a Free-Electron Laser at 109 nm Wavelength
format: journal article
publisher: Physical Review Letters
year: 2000
145 authors: J. Andruszkow | B. Aune | V. Ayvazyan | N. Baboi | R. Bakker | V. Balakin | D. Barni | A. Bazhan | M. Bernard | A. Bosotti | J. C. Bourdon | W. Brefeld | R. Brinkmann | S. Buhler | J. P. Carneiro | M. Castellano | P. Castro | L. Catani | S. Chel | Y. Cho | S. Choroba | E. R. Colby | W. Decking | P. Den Hartog | M. Desmons | M. Dohlus | D. Edwards | H. T. Edwards | B. Faatz | J. Feldhaus | M. Ferrario | M. J. Fitch | K. Floettman | M. Fouaidy | A. Gamp | T. Garvey | C. Gerth | M. Geitz | E. Gluskin | V. Gretchko | U. Hahn | W. H. Hartung | D. Hubert | M. Huening | R. Ischebek | M. Jablonka | J. M. Joly | M. Juillard | T. Junquera | P. Jurkiewicz | A. Kabel | J. Kahl | H. Kaiser | T. Kamps | V. V. Katelev | J. L. Kirchgessner | M. Koerfer | L. Kravchuk | G. Kreps | J. Krzywinski | T. Lokajczyk | R. Lange | B. Leblond | M. Leenen | J. Lesrel | M. Liepe | A. Liero | T. Limberg | R. Lorenz | H. H. Lu | F. H. Lu | C.4 Magne | M. Maslov | G. Materlik | A. Matheisen | J. Menzel | P. Michelato | W. D. Moeller | A. Mosnier | U. C. Mueller | O. Napoly | A. Novokhatski | M. Omeich | H. S. Padamsee | C. Pagani | F. Peters | B. Petersen | P. Pierini | J. Pflueger | P. Piot | B. Phung Ngoc | L. Plucinski | D. Proch | K. Rehlich | Sven Reiche | D. Reschke | I. Reyzl | J.B. Rosenzweig | J. Rossbach | S. Roth | E. L. Saldin | W. Sandner | Z. Sanok | H. Schlarb | G. Schmidt | P. Schmueser | J. R. Schneider | E. A. Schneidmiller | H. J. Schreiber | S. Schreiber | P. Schuett | J. Sekutowicz | L. Serafini | D. Sertore | S. Setzer | S. Simrock | B. Sonntag | B. Sparr | F. Stephan | V. A. Sytchev | S. Tazzari | F. Tazzioli | M. Tigner | M. Timm | M. Tonutti | E. Trakhtenberg | R. Treusch | D. Trines | V. Verzilov | T. Vielitz | V. Vogel | G. v. Walter | R. Wanzenberg | T. Weiland | H. Weise | J. Weisend | M. Wendt | M. Werner | M. M. White | I. Will | S. Wolff | M. V. Yurkov | K. Zapfe | P. Zhogolev | F. Zhou
abstract: We present the first observation of self-amplified spontaneous emission (SASE) in a free-electron laser (FEL) in the vacuum ultraviolet regime at 109 nm wavelength (11 eV). The observed free-electron laser gain (approximately 3000) and the radiation characteristics, such as dependency on bunch charge, angular distribution, spectral width, and intensity fluctuations, are all consistent with the present models for SASE FELs.
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title: A High Voltage Extractor with Photocathodes
format: conference proceeding
conference: EPAC 1998
year: 1999
7 authors: G. Travish | D. Giove | P. Michelato | C. Pagani | P. Pierini | L. Serafini | D. Sertore
abstract: We describe a system designed for photocathode testing and beam dynamics studies which is based on a high voltage extractor and a sub–ps drive laser. The system’s distinctive characteristics are the ability to run in the short bunch regime — where the dynamics are not governed by the Child–Langmuir law — and the anticipated availability of both transverse and longitudinal beam diagnostics to determine the full beam distribution. The system consists of a pseudo parallel plate 100 kV DC gun with a removable cathode and a cathode–anode gap of 8 mm, yielding a cathode field of up to 10 MV/m. The drive laser is a Nd:Glass system capable of producing over 200 ?J at 264 nm with a pulse length adjustable from approximately 250 fs to over 1 ps. The goals of the system, described in this paper, are to support ongoing photocathode studies, including measuring high current density extraction from prepared cathodes and investigating the effect of surface variation of the quantum efficiency. Additional studies foreseen include parameterizing the effect of surface variations on the transverse emittance, and exploring beam dynamics such as the short bunch blow out regime which has recently been proposed as a way to produce uniform ellipsoidal charge density distributions[1].
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title: A high current superconducting proton linac for an accelerator driven transmutation system
format: conference proceeding
conference: PAC 1997
year: 1998
7 authors: C. Pagani | G. Bellomo | P. Pierini | G. Travish | D. Barni | A. Bosotti | R. Parodi
abstract: High current CW proton linac accelerators have been recently proposed for a number of applications based on the use of a large flux of spallation neutrons. In this context, an R&D program on an accelerator driven system for nuclear waste transmutation has been recently approved in Italy. Our specific task is to develop, together with the national industry, a design of the high energy part of the proton accelerator, along with prototype development for the most critical components. In this paper we present a revised version of the design proposed at Linac'96, using five cell cavities, rather than the original four cells. This modification, together with a new criterion for using the transit time factor curve for non resonant proton velocities, results in a more modular and efficient design. A 1.6 GeV linac, operated at 25 mA, allows to reach 40 MW beam power. The beam power upgrade is achievable using additional couplers per cavity. (5 References).
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title: TDA3D: Updates and improvements to the widely used three-dimensional free electron laser simulation
format: conference proceeding
conference: FEL 1996 18th
year: 1997
7 authors: B. Faatz | W. Fawley | P. Pierini | Sven Reiche | G. Travish | D. Whittum | J. Wurtele
abstract: TDA3D is a widely distributed and often used Free Electron Laser (FEL) simulation code. While a number of versions of TDA exist, this paper describes the official version which is well tested and supported. We describe the capabilities of the code emphasizing recent improvements and revisions. TDA3D is a steady-state (time-independent) amplifier code. The code self-consistently solves, after averaging over a wiggler period, the paraxial wave equation for the radiation field and the Lorentz equations of motion for the electrons. The paraxial wave equation includes diffraction and optical guiding. The calculation of the electron beam motion takes into account longitudinal bunching and transverse betatron oscillations, so that emittance, energy spread, and external focusing can be properly modeled. Recent additions to the simulation include the ability to model natural wiggler focusing in one or both planes, alternating gradient quadrupoles or sextupoles, and ion channels. The initial loading of the electron distribution can be controlled to allow for matching into focusing channels, improved quiet starts (non-correlated phase-space distributions), and arbitrary energy spread.
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title: Spectrum, temporal structure, and fluctuations in a high-gain free-electron laser starting from noise
format: journal article
publisher: Physical Review Letters
year: 1994
5 authors: R. Bonifacio | L. De Salvo | P. Pierini | N. Piovella | C. Pellegrini
abstract: We study the time structure, the frequency composition, and the shot to shot fluctuations of the radiation emitted by a free-electron laser starting from shot noise in the electron beam longitudinal distribution, taking into account slippage and finite bunch length effects. We find a very different behavior when the bunch length, l/sub b/, is much longer than the cooperation length, l/sub c/, or of the order of a few l/sub c/. The field evolution is dominated by slippage effects in both cases, and shows the presence of superradiant spikes. (14 References).
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title: Short wavelength FELs using the SLAC linac
format: journal article
publisher: presented at the Fourth European Particle Acclerator Conference (EPAC'94), London, England, June 27-Julyy 1, 1994
year: 1994
30 authors: J. Cobb | D. Prosnitz | V. Vylet | J. Seeman | P. Pianetta | P. Morton | H. D. Nuhn | K. Bane | R. Boyce | G. Loew | R. Miller | J. Paterson | D. Palmer | T. Raubenheimer | R. Tatchyn | H. Winick | A. D. Yeremian | C. Pellegrini | J.B. Rosenzweig | G. Travish | E. T. Scharlemann | W. M. Fawley | K. Halbach | K. J. Kim | R. Schlueter | Sessler, A. M. | M. Xie | R. Bonifacio | L. De Salvo | P. Pierini
abstract: We have studied the use of the SLAC linac to drive FELs at wavelengths down to a few angstroms. Lasing would be achieved in a single pass of a low emittance, high peak current, high energy eelctron beam through a long undulator by Self-Amplified-Spontaneous-Emissin (SASE). About 10(13) photons per pulse can be produced in 100 fs pulses at a 120 Hz rate, corresponding to brightness levels of about 10(22) average and 10(32) peak. Peak power levels are tens of GW. Electron energies of 10-20 GeV are required. Signifcant imporvement of FEL performance seems possible using harmonic generation techniques according to results from numerical simulations.
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title: Prospects for high power linac coherent light source (LCLS) development in the 1000 angstrom-1 angstrom wavelength range
format: conference proceeding
conference: International Colloquium on X-Ray Lasers 4th
year: 1994
26 authors: R. Tatchyn | K. Bane | R. Boyce | G. Loew | R. Miller | H. D. Nuhn | D. Palmer | J. Paterson | T. Raubenheimer | J. Seeman | H. Winick | D. Yeremian | C. Pellegrini | J.B. Rosenzweig | G. Travish | D. Prosnitz | E. T. Scharlemann | S. Caspi | W. Fawley | K. Halbach | K. J. Kim | R. Schlueter | M. Xie | R. Bonifacio | L. De Salvo | P. Pierini
abstract: Electron bunch requirements for single-pass saturation of a free-electron laser (FEL) operating at full transverse coherence in the self-amplified spontaneous emission (SASE) mode include: 1) a high peak current, 2) a sufficiently low relative energy spread, and 3) a transverse emittance epsilon (r-m) satisfying the condition epsilon <= lambda /4 pi , where lambda (m) is the output wavelength of the FEL. In the insertion device that induces the coherent amplification, the prepared electron bunch must be kept on a trajectory sufficiently collinear with the amplified photons without significant dilution of its transverse density. In this paper we discuss a Linac coherent light source (LCLS) based on a high energy accelerator such as, e.g., the 3 km S-band structure at the Stanford Linear Accelerator Center (SLAC), followed by a long high-precision undulator with superimposed quadrupole (FODO) focusing, to fulfill the given requirements for SASE operation in the 1000 angstrom-1 angstrom range. The electron source for the linac, an RF gun with a laser-excited photocathode featuring a normalized emittance in the 1-3 mm-mrad range, a longitudinal bunch duration of the order of 3 ps, and approximately 10(-9) C/bunch, is a primary determinant of the required low transverse and longitudinal emittances. Acceleration of the injected bunch to energies in the 5-25 GeV range is used to reduce the relative longitudinal energy spread in the bunch, as well as to reduce the transverse emittance to values consistent with the cited wavelength regime. Two longitudinal compression stages are employed to increase the peak bunch current to the 2-5 kA levels required for sufficiently rapid saturation. The output radiation is delivered, via a grazing-incidence mirror bank, to optical instrumentation and a multi-user beam line system. Technological requirements for LCLS operation at 40 angstroms, 4.5 angstroms, and 1.5 angstroms are examined.
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title: A Study of Linewidth, Noise and Fluctuations in a FEL Operating in SASE
format: conference proceeding
conference: FEL 1993 15th
year: 1994
5 authors: Bonifacio, R. | De Salvo, L. | P. Pierini | Piovella, N. | C. Pellegrini
abstract: We study the evolution of the FEL radiation intensity and spectrum starting from noise in the electron beam longitudinal distribution. Due to the slippage both the time and frequency structure of the emitted radiation pulse show a very different behavior when the bunch length is much longer than or of the order of the cooperation length l(c). The occurrence of superradiant spikes is discussed. We present analytical and numerical results.
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title: A millimeter wave FEL driven by a photocathode RF linac
format: conference proceeding
conference: FEL 1993 15th
year: 1994
11 authors: R. Zhang | C. Pellegrini | J.B. Rosenzweig | G. LeSage | F. Hartemann | D. McDermott | C. Joshi | N. Luhmann | P. Pierini | de Salvo, L. | Bonifacio, R.
abstract: We present the design of a millimeter wave FEL based on the UCLA photocathode RF linac. The linac energy can be varied between 5 and 18 MeV. The electron pulse duration is 2 ps FWHM, with a peak current exceeding 150 A. The FEL is designed to operate in the high-gain Compton regime, controlling the slippage with the propagating radiation in a waveguide. The design permits the exploration of the basic FEL physics in this regime, including the exploration of saturation and lethargy in the superradiant and steady state regime. (15 References).
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title: Slippage, noise and superradiant effects in the UCLA FEL experiment
format: conference proceeding
conference: FEL 1993 15th
year: 1994
5 authors: R. Bonifacio | P. Pierini | C. Pellegrini | J.B. Rosenzweig | G. Travish
abstract: We present the results of numerical calculations of the effects of noise, slippage and superradiance in the UCLA infrared (IR) free electron laser (FEL). The experiment, which uses a high brightness electron beam produced by a photocathode RF gun and a 1.5 cm period planar undulator, compares the FEL evolution starting from noise to that starting from an input signal. Numerical studies indicate that we can observe saturation, optical guiding effects and a superradiant spike.
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title: The SLAC soft X-ray high power FEL
format: conference proceeding
conference: FEL 1993 15th
year: 1994
23 authors: C. Pellegrini | J.B. Rosenzweig | G. Travish | K. Bane | R. Boyce | G. Loew | P. Morton | H. D. Nuhn | J. Paterson | P. Pianetta | T. Raubenheimer | J. Seeman | R. Tatchyn | V. Vylet | H. Winick | K. Halbach | K. J. Kim | M. Xie | D. Prosnitz | E. T. Scharlemann | R. Bonifacio | L. De Salvo | P. Pierini
abstract: We discuss the design and performance of a 2 to 4 nm FEL operating in self-amplified spontaneous emission (SASE), using a photoinjector to produce the electron beam, and the SLAC linac to accelerate it to an energy of about 7 GeV. Longitudinal bunch compression is used to increase the peak current to 2.5 kA, while reducing the bunch length to about 40 mu m. The FEL field gain length is about 6 m, and the saturation length is about 60 m. The saturated output power is about 10 GW, corresponding to about 10/sup 14/ photons in a single pulse in a bandwidth of about 0.1%, with a pulse duration of 0.16 ps. Length compression, emittance control, phase stability, FEL design criteria, and parameter tolerances are discussed. (15 References).
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