We have set up a variable length gas cell for electron acceleration, in collaboration with LPGP team from Université d’Orsay (see figure 1). A calibration, off line, gas has been performed by interferometric methods, given the relation between the backing pressure and the estimated neutral density inside the cell. These data have been completed by fluid simulations to determine the longitudinal density profile inside the cell. A typical one is reported on figure 2 for different apertures in front/back of the cell.
We have chosen to work with the ionization injection scheme to maximize the charge inside the electron bunch. Typical spectra obtained with UHI100 laser is reported on figure 3.
Fig 3: typical 10 consecutive shots (left) and the corresponding averaged spectrum (right) recorded on UHI100 laser facility
Reference :
« Gas cell density characterization for laser wakefield acceleration »
Audet TL, Lee P, Maynard G, Dobosz Dufrénoy S, Maitrallain A, Bougeard M, Monot P et Cros B, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment., January, (2018).
Funding :
Collaborators :
LGPG (B. Cros, G. Maynard, T. Audet)