Problem with GPS

Dear all,

I am running a simulation. I aim to create a 10-degree angle using GPS, but I’m encountering an issue where my results remain unchanged regardless of whether the angle is defined or not in my run.mac file. Could someone advise me on how to properly utilize GPS to adjust angles?

this is in my run.mac file

/control/verbose 2
/run/verbose 2

/gps/particle alpha
/gps/energy 5 MeV

/gps/direction 0. 0. 1.
/gps/pos/type Beam
/gps/pos/centre 0. 0. 0. mm
/gps/pos/halfx 2.5 mm
/gps/pos/halfy 2.5 mm

/gps/pos/sigma_x 2.5 mm
/gps/pos/sigma_y 2.5 mm
/gps/ang/mintheta 0 deg
/gps/ang/maxtheta 30 deg
/gps/ang/minphi 0 deg
/gps/ang/maxphi 360 deg

/run/printProgress 100
/run/beamOn 10000000


Geant4 Version: geant4-v11.1.3

_Operating System: Ubuntu 20.04.6 LTS

_Compiler/Version: c++


I am not sure if beam position type allows to define angles… Maybe a planar surface as position type would do the trick, like this?


thank you it works with planar surface

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