Problem 2292

Summary:	subCutoff production
Product:	Geant4	Reporter:	michel.maire
Component:	processes/electromagnetic	Assignee:	Vladimir.Ivantchenko
Status:	RESOLVED WONTFIX
Severity:	minor	CC:	daren.sawkey, michel.maire
Priority:	P4
Version:	other
Hardware:	All
OS:	All
Attachments:	macro for TestEm5 picture past subcutoff feature plot : vertex position of secondaries

Description michel.maire 2020-11-21 18:29:23 CET

Created attachment 645 [details]
macro for TestEm5

HI Vladimir,
In the old Geant4 web pages, there is an exercice demonstrating the subCutoff mechanism :

https://geant4.web.cern.ch/sites/geant4.web.cern.ch/files/geant4/collaboration/working_groups/electromagnetic/gallery/elossPlus/ElossPlus.html

Recently, after a User Forum question, I have tried to redo the exercice. Result seems to at opposite of what we expect.

I attach macro and picture.

Comment 1 michel.maire 2020-11-21 18:32:23 CET

Created attachment 646 [details]
picture

Comment 2 Vladimir.Ivantchenko 2020-11-23 11:06:56 CET

Hi Michel,

thanks for pointing to the problem. This feature was not used for a long time. After the 10.7 release will be out let us try to understand what is going wrong.

Vladimir

Comment 3 Vladimir.Ivantchenko 2021-01-31 10:19:03 CET

Hello Michel,

I have submitted MR 1555, which fix UI commands and add macro subcut.mac to TestEm5. For me sub-cut mechanism is working. It is useful when Opt0 EM physics is used with relatively high cut (like 1 mm), because it should more strong cuts in selected regions. Overall efficiency and advantage of the method is not clear. It is not confirmed by any application, that it is better than simply apply Opt4.

The problem you had with your macro was in usage of "deactivation" UI command for msc and bremsstrahlung. In general, this contradicts to any fine tuning methods used in Geant4 EM. In macro added to TestEm5 these commands are not included.

Vladimir

Comment 4 michel.maire 2021-02-03 19:05:04 CET

Created attachment 667 [details]
past subcutoff feature

Comment 5 michel.maire 2021-02-03 19:07:11 CET

Hello Vladimir,

 I send the picture we got in the past

Comment 6 michel.maire 2021-02-04 18:49:03 CET

Created attachment 669 [details]
plot : vertex position of secondaries

take testem5-V10-07-02

Comment 7 Vladimir.Ivantchenko 2021-03-09 14:29:01 CET

Hi Michel,

I believe in 10.7ref02 it is working somehow butit was decided to drop this option in the new release, so the fix will not be provide for the patch.

Vladimir

Comment 8 michel.maire 2021-03-09 21:17:48 CET

the problem is not solved. But ok for wont fix !