Random vector arround a fixed direction

ROOT
1

Dear developpers,

I would like to know if you have in ROOT the possibility to generate a random vector arround a fixed vector. Use case: you have in a MC a particle momentum and you want to smear it according to an angular resolution (in 3D) which in turn may depend on the momentum intensity.

Regards
Jean-Eric

2

Hi Jean-Eric,

I agree that this would be a nice feature to have in TVector3, TLorenztVector or equivalent. On the Net, I have found this reference where some work
in this direction has been done
www-sldnt.slac.stanford.edu/nld/ … t/root.htm
ftp://ftp.slac.stanford.edu/groups/lcd/RootApps/V3.5/

They were even considering the case with a magnetic field.

If you plan to implement something, let us know.

Rene