Energy Loss and Charge Transfer of Argon in a Laser-Generated Carbon Plasma

Abstract

This Letter reports on the measurement of the energy loss and the projectile charge states of argon ions at an energy of 4 MeV/u penetrating a fully ionized carbon plasma. The plasma of n(e)≈10(20) cm(-3) and T(e)≈180 eV is created by two laser beams at λ(Las)=532 nm incident from opposite sides on a thin carbon foil. The resulting plasma is spatially homogenous and allows us to record precise experimental data. The data show an increase of a factor of 2 in the stopping power which is in very good agreement with a specifically developed Monte Carlo code, that allows the calculation of the heavy ion beam's charge state distribution and its energy loss in the plasma.

High energy density physics research at IMP, Lanzhou, China

“…This effect is especially pronounced at lower ion energies (E ∼ keV/u), where an enhancement factor of up to 35 has been observed [23] . Due to the strong nonlinear effects and their special importance in ICF research, more and more emphasis has been given to investigations of ion beams in the low energy range and/or of plasma with high intensity [18,[24][25][26] . In this section, the recent progress in research on low energy ion interaction with plasma is briefly introduced.…”

“…The motivations are mainly as follows: (1) the most important processes in heavy-ion-driven HED and in the burning of inertial confinement fusion (ICF) fuel; (2) plasma devices could serve as important accelerator equipment to focus an ion beam (so-called plasma lens) and/or to strip an ion beam (so-called plasma stripper) [20][21][22][23][24][25][26] .…”

A spectrometer on chemical vapour deposition-diamond basis for the measurement of the charge-state distribution of heavy ions in a laser-generated plasma

“…[4][5][6] It is thus of great interest to measure the energy loss of the ion beam and its charge-state proportions simultaneously, both time-resolved and after the interaction with the plasma. For this purpose, experiments 16 were conducted in which a thin carbon foil was heated to plasma state using the nhelix and Phelix lasers, and ion bunches from the UNILAC at 108 MHz frequency with several thousand ions per bunch interacted with the plasma (see also Sec. III A).…”

Simulations of the energy loss of ions at the stopping-power maximum in a laser-induced plasma

“…2 over the first 15 nanoseconds of the interaction. Uncertainties on the simulated plasma parameters that arise from the comparison with interferometry data [5] lead to a 5 % error on the calculated energy loss. As expected, the energy loss increases in plasma due to the more efficient energy transfer to free electrons and the increase in the projectile charge state.…”

“…[5]: a 100 µg/cm 2 planar graphite foil is irradiated from both sides by laser beams at 532 nm wavelength, 30 J energy, 7 ns pulse length at FWHM and 1 mm focus spot diameter obtained by using random phase plates for spatial beam smoothing. In this way, a hot carbon plasma with an electron density n e ≤ 10 21 cm −3 and an electron temperature T e ≤ 200 eV is generated.…”