SLitrani: Problem inserting TGeoArb8 Geometry

Geometry
1

Hello,

I have a problem with inserting a TGeoArb8 geometry into my SLitrani simulation instead of a TGeoTrd1, TGeoTrd2 or TGeoBBox for the crystal.
With the three latter ones the simulation is running fine, but if I use the TGeoArb8 class I got warning messages which are similar to the following (except the “step”):

K TLitPhoton::AgainstRev Step should be infinitesimal step: 8.74329075496
I photon: 1169 | global photon nb: 1169

These warnings occur in the following lines in the SLitrani specific TLitPhoton class:

…
if (TLit::Get()->GetTestCalc()) {
// step backward must be small. Else : error
Double_t step = gGeoManager->GetStep();
if (step>0.01) {
fAnomaly = kTRUE;
fPhtLive = kTRUE;
gCleanOut->MMR(killthis,met,“Step should be infinitesimal”,“step”,step,ClassName());}}
…

That means to me, that this problem has definitely something to do with the modified crystal geometry (TGeoXXXX → TGeoArb8) and therefore with the connected step size (“gGeoManager->GetStep();”).

I also attached my macro (test.C). The dimensions of the crystal geometry is defined and calculated starting in line 128 and the TGeoVolume is called at 315.

Can anybody of you tell me what I am doing wrong?

Best regards…tob
test.C (15 KB)

2

your script references non-ROOT classes like TlitMedium, etc.
Could you provide the strict minimum to reprodyuce and understand your problem?

Rene

3

You are right, TLitMedium is one of the SLitrani classes

http://irfu.cea.fr/pisp/gentit/SLitrani/code/SLitraniCode/ClassIndex.html
(SLitrani should be installed in order to run it)

I try to minimize the macro a little bit, it’s attached.
Only focus on lines 315-317.

The problem is:
If I create my crystal via TGeoTrd1, TGeoTrd2 or something similar, it works!
If I create my crystal via TGeoArb8, it fails and I get my said messages!

I also didn’t found any example macros using TGeoArb8.
Is SLitrani may be not able to handle the TGeoArb8 class?
Is there may an other possibility to realize a tapered crystal?

Thx for your help, tob
test_min.C (15 KB)

4

Hi,
I have the same problem with TGeoArb8 and SLitrani, I suppose it’s a bug of this Monte Carlo…I am trying to use TLitTrap, but it seems it gives the same error…Asking to mr. Gentit is not useful beacause he simply doesn’t answer e-mails!
If I manage to fix it I will let you know…
best regards
Stefano

5

Hello,

I’m having the same problem while using the TGeoXtru geometry.

I got warning messages which are similar to the following (except the “step”):

K TLitPhoton::AgainstRev Step should be infinitesimal step: 0.35
Does someone already solved this issue?

thanks,

1 Like