Absolute energy distribution of hard x rays produced in the interaction of a kilohertz femtosecond laser with tantalum targets

作者：Gobet F^*; Hannachi F; Aleonard M M; Chemin J F; Claverie G; Gerbaux M; Malka G; Scheurer J N; Tarisien M; Blasco F; Descamps D; Dorchies F; Fedosejevs R; Fourment C; Petit S; Meot V; Morel P; Hanvey S; Robson L; Liesfeld B

来源：Review of Scientific Instruments, 2006, 77(9): 093302.

DOI：10.1063/1.2337086

Previous reports have indicated the anomalous excitation rate for the 6.2 keV nuclear level of Ta-181 in a plasma produced with a femtosecond laser. A detailed characterization of the electrons and x-ray sources produced in such a plasma is required to interpret these results. In a preliminary work, the continuous energy distribution of hard x rays (10-500 keV) produced in the interaction of a kilohertz femtosecond laser beam with a tantalum solid target is investigated in the 3x10(15)-6x10(16) W/cm(2) range of intensity. A sodium iodide detector with appropriate shielding is used. Strong collimation and absorption filters are used to avoid the pileup of photons in the detector. The response function of this setup is calculated with the GEANT3 simulation code. We demonstrate the necessity to quantify the Compton scattered events in the raw spectra in order to restore the absolute x-ray energy distribution.

• 出版日期2006-9
• 单位中国地震局