(a) Multiple scattering and energy loss in absorber are now calculated
using absorber material properties (density, radiation-length, ...).
(b) All the informations about the absorber are get from the geometry rootfile
instead of from constants in AliMUONConstant.
(c) The track extrapolation to vertex has been removed from the tracking
procedure since the vertex is not known at this level.
(d) An option has been added to cancel the track extrapolation to vertex
when filling ESD in AliMUONReconstructor. ESD are then filled with track
parameters at the first chamber. Similar option have been added in
MUONmassPlot_ESD.C and MUONefficiency.C to perform extrapolation at
this level if not done before. (a detailled mail will follow this commit).
(Philippe P.)