Core dump , microelectron

Geometry, Fields and Transportation
1

hi everyone. I am new in geant4. I just have a very simple question. I want to simulate UFSD Detector and I am starting with a microelectronic example. I just change the material of the world from silicon to air and a core dump happens. is anyone know the reason?and what should I do?
thanks, a lot.

  • G4Exception : em0002
    issued by : G4MicroElecMaterialStructure::ReadMaterialFile
    file /usr/local/geant4/data//G4EMLOW8.0/microelec/Structure/Data_.dat not found!
    *** Fatal Exception *** core dump ***
    **** Track information is not available at this moment
    **** Step information is not available at this moment
2

post the exact line with your changes.
Frequent mistake is to mix up upper and lower case, is it G4_AIR that you use?

https://geant4-userdoc.web.cern.ch/UsersGuides/ForApplicationDeveloper/html/Appendix/materialNames.html

3

I define air in this way :

//Define Air
G4double A = 14.01 * g/mole;
G4double Z = 7;
G4Element* elN = new G4Element (“Nitrogen”, “N”, Z, A);

//Define Oxygen
A = 16.0 * g/mole;
Z = 8;
G4Element* elO = new G4Element (“Oxygen”, “O”, Z, A);

G4Material* Air = new G4Material(“Air”, 1.29mg/cm3, 2);
Air → AddElement(elN, 70perCent);
Air → AddElement(elO, 30*perCent);

fSolidWorld = new G4Box(“World”, //its name
fWorldSizeX/2,fWorldSizeY/2,fWorldSizeZ/2); //its size

fLogicWorld = new G4LogicalVolume(fSolidWorld, //its solid
Air, //its material
“World”); //its name

and I didn’t get any errors
thanks in advance

4

You are missing a * between 70 and perCent

5

No, it’s there. The asterisk between “1.29” and “mg” got combined with the asterisk between “70” and “perCent” to be interpreted as “*text*” and everything from “mg/…” to “…70” was rendered in italics.

When quoting blocks of text, put a special line of three backquotes before and after the block. Thus:
```
here’s some text I want rendered literally
```
will be displayed as

here's some text I want rendered literally
6

Hi Geant folks, I am trying to do exactly the same thing as saharRnj mentioned with the microelectronics example and I get the same outcome of a core dump when I change the material of the world from silicon to air. It still occurs when I define air manually instead of pulling from the nist material database.

Why is this happening? The example says it specifically shows how to use the G4MicroElecPhysics or G4MicroElecPhysicsSi processes and combine them with standard EM physics processes. In PhysicsList.cc of the example it includes comments that makes it clear that the standard EM processes are being applied for the world, and the MicroElec processes are NOT active in the world. So we should be able to change the material of the world to other materials not included in MicroElec models, right?

I thought Geant was able to use different EM physics models in different G4 regions.

Any help would be appreciated. Thanks.

7

I have recreated this error and get the same issue. It looks like it gets structural data from the path

share/Geant4-11.0.0/data/G4EMLOW8.0/microelec/Structure/

If you look in that folder there are only a few materials listed. In fact, these materials are also listed in the example README

You can change the type of the target material
(G4_Ag G4_Al G4_C G4_Cu G4_Ge G4_KAPTON G4_Ni G4_Si G4_SILICON_DIOXIDE G4_Ti G4_W),
if you uncomment one line (/microelectronics/det/setMat) into the .mac file.

I have confirmed that using Al works fine. In fact, this website says only Silicon works, the other materials must have been added in a newer version

The readme also lists the corresponding authors and their emails. I would reach out to them to see if they can add the materials properties that you require.

8

@loydms, I noticed this too, this example is limited in that it only includes the data files for those 11 silicon based materials. If there’s not a simple workaround to use different materials in different regions, I’ll reach out to the authors. Just wanted to check if anyone else had any ideas.