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## CONS310 Branching Ratios and Particle Decay Modes

Routine ID: CONS310
Author(s): Submitted: 23.01.84
Origin: R.Brun, G.N.PatrickRevised: 19.10.94
IPART
( INTEGER) GEANT particle number;
BRATIO
( REAL) array of branching ratios in %, maximum 6;
MODE
( INTEGER) array of partial decay modes.
GSDK stores the branching ratios and partial decay modes for two and three body particle decays into the data structure JPART. The decay modes should be coded into the array MODE such that: MODE(I) = $104$ N3 + $102$ N2 + N1 for I=1,$...$ ,6

where:

N1
particle number for decay product 1;
N2
particle number for decay product 2;
N3
particle number for decay product 3 (if any).
It is important to note the following:
• prior to calling GSDK, all parent and secondary particles should have been defined by GSPART;
• if less than six decay modes are defined the remaining elements of BRATIO and MODE must be set to zero.
For a given particle, IPART, the decay parameters are stored into the JPART data structure as follows:

JPA
= LQ(JPART-IPART) pointer to the bank containing the information on the particle IPART;
JDK1
= LQ(JPA-1) pointer to branching ratios bank;
JDK2
= LQ(JPA-2) pointer to decay modes bank;
BR(I)
= Q(JDK1+I) $Ith$ branching ratio;
MODE(I)
= IQ(JDK2+I) $Ith$ decay mode, where I=1,$...$ ,6.
When a particle decays during tracking, the routine GDECAY is called. If branching ratios and modes have been stored by GSDK, then GDECAY generates the decay products in the 2- or 3-body phase space. If no branching ratios have been defined by GSDK, the user routine GUDCAY is called, where the user can code special decay modes and branching ratios. All data taken from Aguilar Benitez [].

P.Zanarini, S.Giani DRAW001

Next: DRAW001 Introduction to Up: GEANT Previous: CONS300 Particle definition

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