Simulation of enhanced characteristic x rays from a 40-MeV electron beam laser accelerated in plasma

Abstract

Simulation of x-ray generation from bombardment of various solid targets by quasimonoenergetic electrons is considered. The electron bunches are accelerated in a plasma produced by interaction of 500 mJ, 30 femtosecond laser pulses with a helium gas jet. These relativistic electrons propagate in the ion channel generated in the wake of the laser pulse. A beam of MeV electrons can interact with targets to generate x-ray radiation with keV energy. The MCNP-4C code based on Monte Carlo simulation is employed to compare the production of bremsstrahlung and characteristic x rays between 10 and 100 keV by using two quasi-Maxwellian and quasimonoenergetic energy distributions of electrons. For a specific electron spectrum and a definite sample, the maximum x-ray flux varies with the target thickness. Besides, by increasing the target atomic number, the maximum x-ray flux is increased and shifted towards a higher energy level. It is shown that by using the quasimonoenergetic electron profile, a more intense x ray can be produced relative to the quasi-Maxwellian profile (with the same total energy), representing up to 77% flux enhancement at K energy.

Propagation of circularly polarized quadruple Gaussian laser beam in magnetoplasma

“…This refractive index change leads to relativistic self-focusing of laser beams in a plasma [7][8][9]. This phenomenon has great significance because it can produce ultrashort laser pulses(≤ 1ps), ultra high powers(≥ to 1 TW) and high intensities (≥ to 10 18 W/cm 2 ) over distances much greater than the Rayleigh length, as a result of which new plasma effects are observed [10][11][12].…”

The effects of circularly polarized laser pulse on generated electron nano-bunches in oscillating mirror model

“…The recent rapid advances in ultra-intense short pulse lasers and their numerous applications stimulated the research activities in this field such as generation of high energy electron and ion beams and their acceleration (Kawata et al, 2005;Mangles et al, 2006;Chyla, 2006;Bessonov et al, 2008;Sadighi-Bonabi et al, 2010sc, 2011 mono-energetic electron beam (Glinec et al, 2005;Zobdeh et al, 2008;Sadighi-Bonabi et al, 2009a;2010a;2010b), monoenergetic ion beam generation (Badziak, 2005), X-ray emission (Nikzad et al, 2012), high harmonic generation, and X-ray lasers (L'Huillier et al, 1993). Among all possible applications of laser, produced X-rays are useful for inertial confinement fusion (ICF) (Keith Matzen et al, 2005;Yazdani et al, 2009;Sadighi-Bonabi et al, 2010d), which is the most challenging problem.…”

Investigation by simulation of X-ray beams produced via interactions of suitable quasi-monoenergetic electrons with solid targets

“…X-ray photons are produced by electrons which nor- * E-mail: Lida.nikzad@gmail.com † E-mail: a.ehtesami.sarabi@gmail.com mally have Maxwellian distributions. Simulation of x-ray production has been reported by using quasi-Maxwellian and quasi-monoenergetic distributions for several targets [23]. If quasi-monoenergetic electrons are employed, ultrashort X-rays can be produced [24], and X-ray beams have gained many applications in fields such as crystallography, chemistry, material science, and medicine.…”