Aurora Borealis: Stochastic Cellular Automata Simulations of the Excited-State Dynamics of Oxygen Atoms

摘要

Emissions from the ~1S and ~1D excited states of atomic oxygen play a prominent role in creating the dramatic light displays(aurora Borealis)seen in the skies over polar regions of the Northern Hemisphere. A probabilistic asynchronous cellular automaton model described previously [Seybold, Kier, and Cheng, J Phys Chem 1998, 102, 886-891] has been applied to the excited-state dynamics of atomic oxygen. The model simulates the time-dependent variations in ground(~3P) and excited-state populations that occur under user-defined probabilistic transition rules for both pulse and steady-state conditions. Although each trial simulation is itself an independent "experiment", deterministic values for the excited-state emission lifetimes and quantum yields emerge as limiting cases for large numbers of cells or large numbers of trials. Stochastic variations in the lifetimes and emission yields can be estimated from repeated trials.