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Lars Gislén, Jan O. Mattsson, and Bo Söderberg
An Improved Algorithm for Simulations of Divergent-Light Halos
Applied Optics, Vol. 44, Issue 18, 3638-3645 (2005)

Abstract:
Divergent-light halos are produced when light from nearby light sources is scattered by ice crystals in the atmosphere. We present a theory of divergent-light halos leading to an improved algorithm for the simulation of such halos. Contrary to the algorithm we presented earlier for simulating such halos, the new algorithm includes a mathematically rigorous weighting of the events. The computer implementation is very compact and the whole procedure is elegant and conceptually easy to understand. We also present a new simulation atlas showing halos produced by crystals of different shapes and orientations for a set of elevations of the light source.

LU TP 04-27