Announcements: RISQ 2026 Workshop at UW-Madison, 15-18 June 2026, with the first day the G4CMP day
Agenda:
Problems, problems, problems
Continuing to work on memory leak seen in V10-01-00 falseSLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-585, culprit is in ParticleChangeForPhonon falseSLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-547
Complex identification of "actual" surface position at boundary steps has occasional failures SLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-575
falseSLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-576 Initial tiny (1 pm) step by hole gets treated like electron (looks like improperly cleared cache)
Want better energy scale for subdividing pure-phonon energy deposition
The uses of "Debye energy/temp/freq" should be clearly documented so people know what to put in when adding new materials. Since we don't "really" use the parameter as a Debye-model upper limit (energy cutoff), we should explain what it is used for and why.
Organizing Committee for G4CMP Session at RISQ 2026
Stefan Zatschler, Jesse Lutz, Jared Yamaoka, Ryan Linehan, Jake Inman
Similar tutorials as done at previous workshop, but bigger and better! Beginner and advanced sessions.
Should we require everyone to conform to same G4 and G4CMP versions in advance? Is anyone averse to upgrading for the tutorials?
Might be possible to provide a container with things set up for people to use?
Also planning a "check in" day a week or so before to help people get set up.
If your group has topics for the wider workshop, abstract submission is now open.
We'll be inviting people for "lightning talks" during the G4CMP day.
"This meeting is for us" – suggestions or requests from the community are welcome!
Kelsey will get G4CMP repository moved over to the Organization (https://github.com/G4CMP/) by the end of this week.
Current code in tests directory give some initial intuition for things we want to test – ex. Make sure G4LatticeReader, or mesh electric field, etc., does what we want it to do
Something other projects do: "Any time you create a class, you need to create a unit test for that class"
Unit test coverage in "dark corners," places that are crucial and aren't tested all that much
As releases are tags, would like to have "standard candles" to compare physics output (larger scale regression testing)
Whenever we have a bug, make a unit test based on how you tracked it down, and then add THAT test as a unit test to catch if bug happens again
Important to distinguish "validations" from "unit testing," but CI/CD can allow us to do both of these
G4CMP Development Status – mostly to be punted to next time++
Notable bugs being worked on right now!
falseSLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-572Fix for lattice orientation (falseSLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-480) got lost with V10-00-00 release, now restored
SLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-575, and related SLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-580
Notable bugs not being worked on just yet...
SLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-581 Annoying as heck, but may need a G4 debug build to track down
SLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-576 Not a big deal, as we (currently) force charges' first step to be 1 pm
Notable bugs which might have resolved on their own
SLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-560 This was already fixed on G4 v11 branch, should be good in V10-01-00. Looks like Jake closed this Jira ticket just before this meeting!
UW-M replication note
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Attendees: RL, JY, Jeffrey Glasier, BZ, JB, JL, BL, ZC, SR, EM, ÉM, JI, SQD, IH, MK, ML
Announcements:
Introductions: welcoming Ziyu Cai from Illinois Institute of Technology!
Recent updates on branches: charge reflection bug fix on v10-00-00 harder than thought it would be, so for SCDMS, just rolling back to "no reflections = no reflections" –> will be v10-00-01 (later today!)
Jesse: Having a rule of thumb number here would be very helpful for spin qubit world
Emile: should be a Schottky barrier, and charge needs barrier energy to cross boundary, (but also small probability to cross based on tunneling), and this affects interface
Should suggest to Wade/other developers of this that we should consider adding this to G4CMP either in the code itself or as a guide parameter for a given material/material interface
Then will likely push forward on G4v11
Will merge v10-00-01 onto G4v11 branch, check for conflicts, before putting it out as 10-01-01 – expect this to take a few days to do carefully.
Ryan will test 494 branch with validation scripts once it's ready
Reminder of "Round Robin in 3 weeks" – ÉM, SR, JI, SQD, ZC, BZ, (WL?), RL, SZ
Two small bug-fixes needing fixing → version V10-00-01 (hopefully end of today, but may be tomorrow)
Merged latest develop onto G4v11 (falseSLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-494) integration feature branch, version compatibility amendments to TFR code. Will go out as V10-01-00
Fully backward compatible, no physics changes
Once these are done, people doing development work may need to merge these things onto their branches – Mike will provide guidance
Jake's been seeing end-of-run cleanup segfault, which he's now fixed (double deletion somewhere)
Stefan: knock-on effects of TFR on SCDMS framework (falseSLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-567)
Agenda:
Should generally start looking at Jira tickets and planning for new features
Work plan: things we plan to develop for the next release, but may be useful to have confluence page of the work plan
Validation
Want a fully-publicly-visible validation example with a few different geometries, so that we don't have to guess whether we've broken SCDMS physics
Add HVeV detector for NTL and charge dynamics validation
Have a version of a TFR-compatible geometry that also can be toggled to use KaplanQP
Leads into CI/CD as planned by BZ and SZ
Existing projects:
WL: Going through falseSLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-515, working on charge reflection – trying to support both specular and diffuse reflection
Once happy with falseSLAC JIRAissuekey,summary,issuetype,created,updated,duedate,assignee,reporter,priority,status,resolutionkey,summary,type,created,updated,due,assignee,reporter,priority,status,resolution1b8dc293-975d-3f2d-b988-18fd9aec1546G4CMP-514, should bring 515 up to date with latest develop (but wait for fixes above)
Currently, 100% specular for holes, diffuse for driftElectrons
No surface phonon creation when you have electrons bouncing around at surfaces
May need a flag to enable recombination when charge falls below threshold energy for other processes so that charges don't bounce forever.
