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In order to provide a general framework where the Stark broadening of atomic lines in plasmas can be calculated, we model the plasma stochastic electric field by using the CTRW approach [1,2]. This allows retaining non Markovian terms in the Schrödinger equation averaged over the electric field fluctuations. As an application we consider a special case of a non separable CTRW process, the so called Kangaroo process [3]. An analytic expression for the line profile is finally obtained for arbitrary waiting time distribution functions. An application to the hydrogen Lyman α line is discussed. [ABSTRACT FROM AUTHOR]

In this work, the influence of the turbulent plasma temperature fluctuations brought on the Hα Doppler line shape is investigated. We show that the core of the line profile is modified by the plasma turbulence. The consequences on the ion temperature determination from Doppler line profile analysis are discussed. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this work we analyze the role played by fine structure in the modeling of spectral line shape. In the case of non hydrogenic impurities, fine structure obviously cannot be neglected since the corresponding components are often resolved. This is generally not the case for hydrogenic lines, which have larger Doppler widths. Nevertheless, we show that in some tokamak plasmas conditions fine structure must be taken into account so as to ensure accurate line width measurements. We present a numerical code developed by our group, which is able to calculate line shapes emitted by any kind of atoms perturbed by electric and magnetic fields. Magnetic field effects on fine structure spectra of both impurities and deuterium are investigated for tokamak edge conditions, i.e. for emitter temperature varying from a fraction of eV to a few tens of eV, and for magnetic field in the range of 0–5 teslas. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Large or dense divertor plasmas of magnetic fusion devices can be optically thick to the resonance lines of the hydrogen isotopes. In this work we examine the sensitivity of the line radiation transport to the detailed structure of the spectral profiles. [ABSTRACT FROM AUTHOR]

Modelling of hydrogen line profiles in the ITER divertor plasma entails several challenges. Because of the high density (Ne>1014cm-3) low temperature (kTe<2eV) expected in the magnetized plasma close to the wall, both Stark broadening and Zeeman splitting have to be taken into account in line shape calculations, [1]. Moreover, the conditions are such that the ion dynamics has to be retained in Stark broadening calculations, the presence of a high magnetic field (B∼5T) introduces couplings between Stark and Zeeman effects, which can significantly alter the profile [2,3]. We present here Balmer lines obtained by numerical simulations based on a standard Molecular Dynamics technique, of the plasma in an external magnetic field. The simulated profiles are compared to experimental ones obtained in Plasma Surface Interaction (PSI) experiments which are carried out on Pilot-PSI of FOM. [ABSTRACT FROM AUTHOR]

Profiles of the n = 5-6 (λ = 4658 Å) and n = 6-7 (7726 Å) lines emitted by Li-like carbon C+3 ions have been computed for plasma conditions of tokamak and stellarator divertors (Ne = 1019–1021 m-3, Te = 1–10 eV). The broadening and profiles of these lines are proposed to be used for plasma diagnostic purposes in particular to crosscheck the validity of the plasma parameters determined from the CIV line intensities measured in JT-60U tokamak. [ABSTRACT FROM AUTHOR]