Phase Space Cuts
PhaseSpace
is base class for all hard-process phase-space
generators, either generic 2 -> 1 or 2 -> 2 ones,
or specialized ones like for elastic and diffractive scattering.
In it, it is possible to constrain the kinematics of most processes.
(Exceptions are "soft physics", i.e. minimum bias, elastic and
diffractive processes.) These constraints apply in the rest frame
of the hars subprocess, and topologies normally would be changed
e.g. by subsequent showering activity.
The more particles in the final state, the more cuts can be applied.
Cuts in all processes
parameter name="PhaseSpace:mHatMin" default="4." min="0."
The minimum invariant mass.
parameter name="PhaseSpace:mHatMax" default="-1."
The maximum invariant mass.
A negative value means there is no upper limit.
Cuts in 2 -> 2 processes
parameter name="PhaseSpace:pTHatMin" default="4." min="0."
The minimum invariant pT.
parameter name="PhaseSpace:pTHatMax" default="-1."
The maximum invariant pT.
A negative value means there is no upper limit.
parameter name="PhaseSpace:m3Min" default="2." min="0."
The minimum invariant mass of the first product.
Only applies in cases where this particle can have a variable mass.
parameter name="PhaseSpace:m3Max" default="-1."
The maximum invariant mass of the first product.
Only applies in cases where this particle can have a variable mass.
A negative value means there is no upper limit.
parameter name="PhaseSpace:m4Min" default="2." min="0."
The minimum invariant mass of the second product.
Only applies in cases where this particle can have a variable mass.
parameter name="PhaseSpace:m4Max" default="-1."
The maximum invariant mass of the second product.
Only applies in cases where this particle can have a variable mass.
A negative value means there is no upper limit.
Documentation
flag name="PhaseSpace:showSearch" default="off"
Possibility to print information on the search for phase-space
coefficients that (in a multichannel approach) provides an analytical
upper envelope of the differential cross section, and the
corresponding upper estimate of the cross section. Of interest
for crosschecks by expert users only.