Problem on the Purging Magnet example

Geometry, Fields and Transportation
1

Hi,
I’m trying to import a gridded magnetic field data into my simulation project. So I just try the purging_magnet example. I built the example and run it with /run/beamOn 1。The visualized track is a straight line, showing the field not working. The version I’m using is Geant4 10.06.p02.
To eliminate installation or compiler issues, I downloaded the preinstalled virtual machine from https://geant4.cenbg.in2p3.fr/, however, the problem remains. Then I downloaded an old version, Geant4 10.02.p02, it gives a bended track, possibly the correct behavior.
The screenshot of the Qt window is attached.
Could someone provide some hint on debugging this problem?

G41006
G410061302×863 62.5 KB

2

The vis system provides some debugging aids:

/vis/scene/add/magneticField
/vis/set/extentForField
/vis/set/volumeForField

and similar commands for touchables.

3

Thanks,
By applying the /vis/scene/add/magneticField , the magnetic field configuration seems to be same in the two geant4 version. However, the tracks of the particles are different.

4

By applying /vis/scene/add/magneticField command, the field configuration seems to be same in the two versions. However, the particle tracks are different.

5

Sounds like a bug. We would be very grateful if you would submit a bug report with, if possible, enough information for someone to be able to recreate the problem.

6

I submitted a bug report. I think it should be easy to reproduce the problem because there’s no change to the code.

7

Hi there.
I also check this example on the Geant4.10.06.p02, and it’s also work incorrect (tracks are not bending). Then i checked this example on the Geant4.10.07.p01, and all work correct.
G4.10.07.p01 was builded on windows 10, btw