Hi all

I am looking at radioactive nuclei inventory in radioactive sources. In the example below I wanted to know what would be the decay/buildup for an americium source.

Here is my very simple example, in this case I am only looking at how is Am241 decaying, simple solution of Bateman equation for the parent nuclei which should be of the form 1*exp (-lambda .t)
or in this case the solution which is proposed is N[95-Am-241]/N[95-Am-241] = 1*exp(-7.35294e-11*t) which correspond to exp(-1/ T[size=59]1/2[/size] . t) , there is a ln(2) missing I have the impression. lambda = log(2)/ T1/2

gSystem->Load(“libGeom”);

TGeoManager *geom = new TGeoManager("","");

TGeoElementTable *table = geom->GetElementTable();

TGeoElementRN *Am241 = table->GetElementRN(241,95); // A,Z

Am241->Print();

TGeoMaterial *mat = new TGeoMaterial(“Am241”, Am241, 2.0);

TObjArray *vect = new TObjArray();

vect->Clear();

mat->FillMaterialEvolution(vect,0.001);

TGeoElement *el = (TGeoElement*)vect->At(0);

TGeoElementRN *elem = (TGeoElementRN *)el;

elem->Ratio()->Print();

95-Am-241 ENDF=952410; A=241; Z=95; Iso=0; Level=0[MeV]; Dmass=52.929[MeV];

Hlife=1.36e+10[s]

J/P=5/2-; Abund=0; Htox=3.9e-05; Itox=2e-07; Stat=0

Decay modes:

SpontFiss Diso: 0 BR: 0.000% Qval: 207

Alpha Diso: 0 BR: 100.000% Qval: 5.6378

n entries : 14

N[95-Am-241]/N[95-Am-241] = 1*exp(-7.35294e-11*t)

Please let me know if I have missing a point but my impression is that there is an error.

Thanks in advance

Joachim