Narrow spread electron beams from a laser-plasma wakefield accelerator

TY - GEN

T1 - Narrow spread electron beams from a laser-plasma wakefield accelerator

AU - Wiggins, S. M.

AU - Anania, M. P.

AU - Brunetti, E.

AU - Cipiccia, S.

AU - Ersfeld, B.

AU - Islam, M. R.

AU - Issac, R. C.

AU - Raj, G.

AU - Shanks, R. P.

AU - Vieux, G.

AU - Welsh, G. H.

AU - Gillespie, W. A.

AU - MacLeod, A. M.

AU - Jaroszynski, D. A.

PY - 2009

Y1 - 2009

N2 - The Advanced Laser-Plasma High-Energy Accelerators towards X-rays (ALPHA-X) programme is developing laser-plasma accelerators for the production of ultra-short electron bunches with subsequent generation of incoherent radiation pulses from plasma and coherent short-wavelength radiation pulses from a free-electron laser (FEL). The first quantitative measurements of the electron energy spectra have been made on the University of Strathclyde ALPHA-X wakefield acceleration beam line. A high peak power laser pulse (energy 900 mJ, duration 35 fs) is focused into a gas jet (nozzle length 2 mm) using an F/16 spherical mirror. Electrons from the laser-induced plasma are self-injected into the accelerating potential of the plasma density wake behind the laser pulse. Electron beams emitted from the plasma have been imaged downstream using a series of Lanex screens positioned along the beam line axis and the divergence of the electron beam has been measured to be typically in the range 1-3 mrad. Measurements of the electron energy spectrum, obtained using the ALPHA-X high resolution magnetic dipole spectrometer, are presented. The maximum central energy of the monoenergetic beam is 90 MeV and r.m.s. relative energy spreads as low as 0.8% are measured. The mean central energy is 82 MeV and mean relative energy spread is 1.1%. A theoretical analysis of this unexpectedly high electron beam quality is presented and the potential impact on the viability of FELs driven by electron beams from laser wakefield accelerators is examined.

AB - The Advanced Laser-Plasma High-Energy Accelerators towards X-rays (ALPHA-X) programme is developing laser-plasma accelerators for the production of ultra-short electron bunches with subsequent generation of incoherent radiation pulses from plasma and coherent short-wavelength radiation pulses from a free-electron laser (FEL). The first quantitative measurements of the electron energy spectra have been made on the University of Strathclyde ALPHA-X wakefield acceleration beam line. A high peak power laser pulse (energy 900 mJ, duration 35 fs) is focused into a gas jet (nozzle length 2 mm) using an F/16 spherical mirror. Electrons from the laser-induced plasma are self-injected into the accelerating potential of the plasma density wake behind the laser pulse. Electron beams emitted from the plasma have been imaged downstream using a series of Lanex screens positioned along the beam line axis and the divergence of the electron beam has been measured to be typically in the range 1-3 mrad. Measurements of the electron energy spectrum, obtained using the ALPHA-X high resolution magnetic dipole spectrometer, are presented. The maximum central energy of the monoenergetic beam is 90 MeV and r.m.s. relative energy spreads as low as 0.8% are measured. The mean central energy is 82 MeV and mean relative energy spread is 1.1%. A theoretical analysis of this unexpectedly high electron beam quality is presented and the potential impact on the viability of FELs driven by electron beams from laser wakefield accelerators is examined.

KW - wakefield acceleration

KW - energy spread

KW - laser-plasma interaction

KW - relativistic electron beams

KW - SYNCHROTRON-RADIATION

KW - GENERATION

KW - REGIME

KW - PULSES

U2 - 10.1117/12.820733

DO - 10.1117/12.820733

M3 - Conference contribution

SN - 9780819476333

T3 - Proceedings of SPIE

BT - Harnessing Relativistic Plasma Waves as Novel Radiation Sources from Terahertz to X-Rays and Beyond

A2 - Jaroszynski, Dino A.

A2 - Rousse, Antoine

PB - SPIE-International Society for Optical Engineering

CY - Bellingham

T2 - SPIE Europe Optics + Optoelectronics 2009: Harnessing Relativistic Plasma Waves as Novel Radiation Sources From Terahertz to X-Rays and Beyond

Y2 - 22 April 2009 through 23 April 2009

ER -