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Radiation transport calculations based on the use of propagators (or Green's functions) are presented for the Hg resonance at 254 nm in the complete frequency redistribution regime. This resonance radiation plays a dominant role in the power balance of fluorescent lamps. Recent studies have suggested that transport modes above the fundamental are important in some lamp discharges. The Holstein transmittance function T(R) used to evaluate the probabilities is generated by numerical integration across the line profile at low and medium opacity. Complete hyperfine and isotopic patterns with a Voigt profile for each component are used in the model. A simple analytic expression for T(R) from a pure Lorentzian profile is used at high opacity. The calculation includes radial cataphoresis (a radial-dependent ground state Hg density). Evaluation of propagator matrix elements—probabilities of photons travelling from one cell to another—is done by integrating T(R) with the source points distributed radially across the source cell in cylindrical geometry. A radiation transport matrix or propagator function obtained from direct integration is compared with very detailed Monte Carlo simulations of radiation transport in cylindrical geometry. The probability matrix is then used in a self-consistent fluorescent lamp discharge model. Details of the numerical model are discussed. The trapped decay rates at different discharge currents and temperatures obtained by fluorescent lamp discharge simulations are compared with those calculated from an analytic formula.

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