Landau tail

In practice one uses the quantity —dE/dx)Axy the mean energy loss in a layer of Ax thickness. For finite Ax there will be fluctuations in the actual values, the distrihution will he skewed toward higher values (Landau tail, Landau 1944) and only for thick layers (—dE/dx Ax) will the distribution he Gaussian (see Sect. 9.3.6 in Chap. 9 on the Stochastics and Nuclear Measurements ). 

Leshem, Y., Landau, E.M. and Deutsch, M. 1989. A monolayer model study of surface tension associated parameters of membrane phospholipids. I. Effect of unsaturation of fatty acyl tails. Exp. Bot. (in press). 

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