You can modify the properties of particles, which are stored in the DDDB under param/ParticleTable.txt. This can be useful e.g. in Gauss.

This example is for Gauss v40r2p3. In Gauss-Job.py (or similar) write:

from Configurables import LHCb__ParticlePropertySvc as ParticlePropertySvc
ParticlePropertySvc().Particles = [ "K*_2(1430)0         153         315  0.0        0.100000   1.0e-10                    K_2*0         315        0.0", 
                                    "K*_2(1430)~0        154        -315  0.0        0.100000   1.0e-10               anti-K_2*0        -315        0.0" ]
 
ApplicationMgr().ExtSvc    += [ ParticlePropertySvc() ]

if you want to modify the properties of the K*_2(1430) and its antiparticle. The columns are:

Particle GeantID PDGID CHARGE MASS(GeV) LIFETIME(s) EVTGENNAME PYTHIAID MAXWIDTH