This README file provides instructions for reading the radioactive decay 
schemes in the files zXX.aYYY found in the directory RadioactiveDecay3.2
(most recent version).  This directory, as well as previous versions, is
available from the Geant4 download page 

http://geant4.web.cern.ch/geant4/support/download.shtml

under the Data files heading. In order to use the radioactive decay module
correctly, you must download and unpack the above directory in your local
area, and set the environment variable

G4RADIOACTIVEDATA

to point to it. 

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In each of the files, lines beginning with either a 'W' or a '#' are 
comments.

Lines beginning with a 'P' are headers, each of which describes a level of
the nucleus.  The first number is the excitation energy in keV, the second 
is the half life in seconds. Indented lines under the 'P' lines are decay 
modes for that excitation.  There are two type of records here, 
distinguished by the number of columns.

If there are 3 columns only, this is a header which describes all decays of
that type from this level.  The first column is the decay mode, the second
column is zero, and the third column in the branching ratio to this mode, 
as a fraction of unity.  Therefore, the third columns of all the 3-column
records under a given 'P' line should sum to 1.0.

If there are four columns, this is a record which describes a subset of the 
decay type, specific to a given lower level in the daughter species.  The 
first column is the decay type, the second column is the excitation level 
of the daughter (in keV), and the third column is the branching ratio as a 
percentage (! note... not a fraction of unity) of the total branching ratio 
which came from the 3-column record for this decay.