Overlap in the upstream region nose shielding

[chandabindu]

Environment: (where does this bug occur, have you tried other environments)

• branch (master for latest released): develop
• revision (HEAD for most recent): 84b45e2
• OS or system: ifarm1901
• Special ROOT or Geant4 versions? Geant4.10.06.p02MT, ROOT6.20.04

Steps to reproduce: (give a step by step account of how to trigger the bug)

1. ./build/remoll macros/checkoverlap.mac

Expected Result: (what do you expect when you execute the steps above)

Checking overlaps for volume...... OK!

Actual Result: (what do you get when you execute the steps above)

-------- WWWW ------- G4Exception-START -------- WWWW -------
*** G4Exception : GeomVol1002
issued by : G4PVPlacement::CheckOverlaps()
Overlap with volume already placed !
Overlap is detected for volume UScoil:0 (G4Cons)
with logicUpstreamNoseShieldBeampipe_PV:0 (G4Polycone) volume's
local point (28.9907,8.25721,37.8447), overlapping by at least: 4.85627 mm
NOTE: Reached maximum fixed number -1- of overlaps reports for this volume !
*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------

-------- WWWW ------- G4Exception-START -------- WWWW -------
*** G4Exception : GeomVol1002
issued by : G4PVPlacement::CheckOverlaps()
Overlap with volume already placed !
Overlap is detected for volume logicUpstreamNoseShieldBeampipe_PV:0 (G4Polycone)
with UScoil:0 (G4Cons) volume's
local point (-23.8085,-25.6545,-1007.6), overlapping by at least: 4.85563 mm
NOTE: Reached maximum fixed number -1- of overlaps reports for this volume !
*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------

[rahmans1]

@chandabindu Don't think this is a big problem. Just a small overlap with the mother volume containing the coil subregion. Will get adjusted when we introduce new region separation to have different levels of vacuum. For a quick fix, I can just shorten naz's nose shield by a few mm or hollow out the upstream end of that mother volume a bit more so that the overlap doesn't show up. Don't think it ultimately makes a difference. So, would be low on my priority.

[wdconinc]

The problem I see here is that others can't know what is an important overlap and what isn't. It also makes it seem as though overlaps are OK. We turned on overlap warnings by default for a reason (once the showermax overlaps were finally fixed). We should get this fixed. To me it's the same as with compiler warnings: if you allow some that you "know" are not important, then you give others the implicit permission to not fix their compiler warnings either.

[chandabindu]

Exactly, I was not sure how the problem was.. I just raised this issue to make relevant people aware of this overlap.

…

On Fri, May 7, 2021 at 2:59 PM Wouter Deconinck ***@***.***> wrote: The problem I see here is that others can't know what is an important overlap and what isn't. It also makes it seem as though overlaps are OK. We turned on overlap warnings by default for a reason (once the showermax overlaps were finally fixed). We should get this fixed. To me it's the same as with compiler warnings: if you allow some that you "know" are not important, then you give others the implicit permission to not fix their compiler warnings either. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#488 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AH2AK7JCFOUM52VOFAXENTLTMQ2B7ANCNFSM44KVDZAQ> .

-- Regards, chandan

[rakithab]

@chandabindu @rahmans1 Can either of you comment on the status of this overlap?