Speaker
Josef Krasa
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P5.2015.pdf
Relativistic effects in plasma produced with sub-nanosecond 3-TW laser
J. Krása1, D. Klír2,3, K. Řezáč2,3, J. Cikhardt2,3, M. Krůs1,3, A. Velyhan1, M. Pfeifer1,3,
J. Dostál3,1, R. Dudžák1,3, M. Krupka3, J. Kaufman1,
T. Pisarczyk4, Z. Kalinowska4, T. Chodukowski4
1
Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic
2
Faculty of Electrical Engineering, Czech Technical University in Prague, Czech Republic
3
Institute of Plasma Physics of the Czech Academy of Sciences, Prague, Czech Republic
4
Institute of Plasma Physics and Laser Microfusion, Warsaw, Poland
This contribution deals with observations of relativistic electrons produced in a laser plasma
interaction experiment at the PALS laser system operated at the Institute of Plasma Physics
in Prague, Czechia. The PALS laser is a near-infrared 3-TW iodine laser designed to deliver
irradiance on target of 1016 Wcm-2 in 300 ps pulses at the wavelength of 1.315 m. Plastic
and metallic foils of 50 – 500 m in thickness were irradiated with I2 51016 W cm2 m2.
Under these conditions we have observed relativistic electrons expanding into the vacuum
with maximum energy going beyond 4 MeV in the backward direction, i.e. against of the
focused laser beam. The relativistically accelerated forward electrons passing through foil
targets were directly observed around the normal of the rear target surface. The applied laser
intensity was increased by the self-focusing above the relativistic threshold. Our experiments
have shown that the experimental conditions may be appropriate for thermal and relativistic
self-focusing. The application of a unique femtosecond interferometry technic [1] allowed us
to observe bunches of trapped electrons occurring in the plasma expanding against the
focused laser beam.
[1] T. Pisarczyk, et al., Phys. Plasmas 21, 012708 (2014).
