Total cross-section

Next: PHYS431 Ionisation processes Up: Method Previous: Continuous energy loss

Total cross-section

The integration of formula () gives the total cross-section : $σ(Z,E,T$ _cut) =

$2 πr$ ₀²m {Zβ²}{1-Y+β²YlnYT_cut} $for spin-0 particles$

$2 πr$ ₀²m {Zβ²}({1-Y+β²YlnYT_cut}+ {T_max-T_cut2E²}) $for spin-{1 2} particles$

$.$

The mean free path is tabulated during initialisation as a function of the medium and of the energy by the routine GDRSGA for leptons only.

The cross-section () is strongly dependent on the mass of the incident particle, and cannot be tabulated in a general way for any charged hadrons. Therefore, for such particles, the cross-section is computed at tracking time in the routine GTHADR.

PHYS431

Janne Saarela
Mon Apr 3 12:46:29 METDST 1995

$2 πr$ ₀²m {Zβ²}{1-Y+β²YlnYT_cut}	$for spin-0 particles$
$2 πr$ ₀²m {Zβ²}({1-Y+β²YlnYT_cut}+ {T_max-T_cut2E²})	$for spin-{1 2} particles$