Classical description ofH(1s)andH*(n=2)for cross-section calculations relev

Abstract

In this work, we introduce a classical trajectory Monte Carlo (CTMC) methodology, specially conceived to provide a more accurate representation of charge-exchange processes between highly charged ions and H(U ) and H*(n = 2). These processes are of particular relevance in power fusion reactor programs, for which chargeexchange spectroscopy has become a useful plasma diagnostics tool. To test the methodology, electron-capture reactions from these targets by C6+, N7+, and 0 8+ are studied at impact energies in the 10-150 keV/amu range. State-selective cross sections are contrasted with those predicted by the standard microcanonical formulation of the CTMC method, the CTMC method with an energy variation of initial binding energies that produces an improved radial electron density, and the atomic orbital close-coupling method. The present results are found in to be much better agreement with the quantum-mechanical results than the results of former formulations of the CTMC method.

Uncertainty estimates for theoretical atomic and molecular data

“…At lower energies the discrepancies are larger and different variants of CTMC models give different results [219,222]. This suggests that an uncertainty assessment solely based on CTMC calculations would be difficult in this regime.…”

“…Even though the two-center basis used includes a total of 340 states, which is a very large number for a semiclassical CC calculation, the overestimation is deemed to be a finite-basis effect, i.e. a convergence problem of the AOCC method in this energy range [219,222]. Figure 14 explores the very low energy regime in which straight-line trajectories, and .…”

“…This e sections of Figur We observe bution of the e state of the targ detail, we show n max , after the e energies. In the PHYSICAL REVIEW A 91, 042709 (2015) 2) orbital or the 2p [222].) The AOCC cross sections in both panels are from [218].…”

“…The recommended data are shown in figure 12 as solid lines. In addition, one recent representative is included for each of the following theoretical methods: MOCC [221], AOCC [218], TDL [168], and CTMC [222]. Experimental data on the n-shell resolved level are not available for this collision system.…”

Comment on “Classical description ofH(1s)andH*(n=2)for cross-secti

“…It was found [7] that all these alternatives lead to practically identical electron capture cross sections. In particular, the hydrogenic distribution [4], named hydrogenic-E-distribution (HED) in [8], is constructed as a linear combination with constant coefficients of microcanonical distributions with different energies, E k . Since the microcanonical distributions are stable, the HED is also time independent.…”