Speaker: Vojtech Horný, Institute of Plasma Physics, Czech Academy of Sciences

Abstract:
The pulses of hard X-ray light are demanded by various fields such as fundamental research, medicine, industry or public security. The major advances in the field of ultraintense laser pulse interaction with matter achieved within last decades brought conceptually new sources of X-ray generation. The laser wakefield acceleration of electrons in the gaseous target provides a convenient source of so called betatron radiation, which is emitted due to the transverse oscillations of accelerated electrons. This theoretical talk will introduce the method how to construct the spectrogram which comprises both information about the frequency and temporal profile of generated X-ray signal. Using this method, it was shown that the duration of such pulses can be few femtoseconds or even less, which is beneficial for sampling the fundamental physical processes such as lattice vibrations, chemical reaction or phase transition, which occur on the time scale of about tens of femtoseconds.