Acceleration of protons in plasma produced from a thin plastic or aluminum target by a femtosecond laser

作者：Rosinski M^*; Badziak J; Parys P; Zaras Szydlowska A; Ryc L; Torrisi L; Szydlowski A; Malinowska A; Kaczmarczyk B; Makowski J; Torrisi A

来源：Journal of Instrumentation, 2016, 11(05): C05017.

DOI：10.1088/1748-0221/11/05/C05017

• Plasma generation (laser-produced, RF, x ray-produced)
• Plasma diagnostics - charged-particle spectroscopy
• Detector alignment and calibration methods (lasers, sources, particle-beams)
• Solid state detectors

The acceleration of protons in plasma produced from thin mylar (3.5 mu m) and aluminum (2 mu m) targets by a 45-fs laser pulses with the energy of 400 mJ and the intensity of up to 10(19) W/cm(2) was investigated. Characteristics of forward-accelerated protons were measured by the time-of-flight method. In the measurements, special attention was paid to the dependence of proton beam parameters on the laser focus position (FP) in relation to the target surface which resulted in the intensity change within a factor of similar to 10. It was observed that in the case of using the Mylar target, the dependence of both the maximum (E-pmax) and the mean (< E-p >) proton energy on vertical bar Delta x vertical bar is clearly non-symmetric with regard to the point where FP = 0 (the focal plane on the target surface) and highest proton energies are achieved when the focal plane is situated in front of the target. In particular, for the target with the thickness of 3.5 mu m E-pmax reached 2.2 MeV for FP = +50 mu m while for FP = 0 and FP = 100 mu m the maximum proton energies reached only 1.6 MeV and 1.3MeV, respectively. For the aluminum target of 2 mu m thickness E-p changed only within similar to 40% and the highest proton energies reached 2.4 MeV.

• 出版日期2016-5