Use several instances of the same detector in simulations about r3broot

[hapol]

Hi Anna,
it is not possible to instantiate twice the same detector in two locations. To my understanding there is a single kDetector identifier and energy losses in any of the two objects will fill the same data structure. You should use a different detector (another fiber set)... or modify the code heavily (data structure should be modified to add a detector instance; ProcessHit() should be able to assign the detector instance based on the GEANT volume name, ...). I would recommend to use another similar detector; I do not see other easy solution.
Hope it helps. Cheers

[acorsi]

Hi Hector, I see. The question arises for fibers, and it seems to me that all fibers/fi* classes are very similar (right?) so maybe this is the easy solution, use different ones for different instances. Thanks! Anna

[jose-luis-rs]

I have implemented a general class to make simulations with the fibers, named R3BFiber, below you can find how to invoke it for fiber-30:

if (fFi30){
if (fi30Par) {
fi30Par->printParams();
auto rfib30 = new TGeoRotation("Fi30rot");
rfib30->RotateX(fi30Par->GetRotX());
rfib30->RotateY(fi30Par->GetRotY());
rfib30->RotateZ(fi30Par->GetRotZ());
run->AddModule(new R3BFiber("Fi30", fFi30Geo, DetectorId::kFI30, {fi30Par->GetPosX(), fi30Par->GetPosY(),
fi30Par->GetPosZ(), rfib30}));
} else {
run->AddModule(new R3BFiber("Fi30", fFi30Geo, DetectorId::kFI30, {0., 0., 890.}));
}
}
The parameters used for positioning the fiber (positions and angles) are read from a .par file that should contain the same positions and angles used for the analysis of real data. This allows us to overlap simulations with experiments in a simple way.

An example of macro for the simulation is here:
https://github.com/R3BRootGroup/R3BParams_S522/blob/dev/macros/sim/runsim.C

[jose-luis-rs]

In the folder R3BParams_S522/macros/rootgeo (the same for other parameter repositories) you can find all the macros to create the root geometry of each detector. There is also a script named "setgeo.sh" that generates everything automatically doing (don't forget to load your config.sh file before executing this script):
. setgeo.sh