  New stable particles with fairly low masses could exist if the coupling to
the Standard Model is weak, and with suitable parameters they might be possible
to produce at the LHC. Here we study a selection of models with the new
particles being charged under a new gauge group, either U(1) or SU(N). In the
Abelian case there will be radiation of gammavs, which decay back into the SM.
In the non-Abelian case the particles will undergo hadronization into mesons
like states piv/rhov that subsequently decays. We consider three different
scenarios for interaction between the new sector and the SM sector and perform
simulations using a Hidden Valley model previously implemented in PYTHIA. In
this study we illustrate how one can distinguish the different models and
measure different parameters of the models under conditions like those at the
LHC.
