Some notes on Alkali-He SEOP
نویسنده
چکیده
The factor σ is called the interaction cross section and has units of area. It is the probability of a single interaction per unit target point density per unit target region length. A cross section is useful because it isolates the part of the interaction probability that is due to the mechanism of the interaction. An equivalent definition of cross section is the probability of interaction per unit flux, where flux φ is the number of target points per unit cross sectional area. The interaction rate γ is defined as the probability of an single interaction per unit time:
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