The May 2018 Offline Leads status update was handled via email and a google document.

Note, item 4 under LArSoft requests a response from each experiment. Please email Katherine Lato and Erica Snider.

LArSoft – Erica Snider

1. Event display:  As reported at the last LArSoft Coordination Meeting, the initial set of requirements for a new common event display framework have been approved. The next step, to be completed before the summer, is to define evaluation criteria and identify potential technical solutions. The plan will be to attempt to perform the evaluation over the summer.
2. LArG4 re-factoring:  Initial testing of a fully re-factored LArG4 and Geant4 within a stand-alone testing environment has been completed. Further testing requires integrating the re-factored LArG4 into LArSoft. This work is now under way. Two of the three downstream modules needed to complete the re-factoring have also been completed, an electron drift module written by Bill Seligman, and a fast photon propagation module, written by Wes Ketchum. Some work may be required to ensure that the necessary workflows are easily adapted to the needs of all experiments. The next phase of this project will address light from the Large Electron Multiplier in dual-phase LArTPCs. A later phase will address the issue of integrating multiple external detector types into the simulation, as will be required for DUNE ND. We  note that the current re-factoring introduces some of the necessary concepts into the geometry.
3. Re-architecting services for thread safety:  While Mike Wang was pulled away until mid-July, Paul Russo may be able to start work on this once multi-threaded art is released which is expected soon.
4. Heidi Schellman has raised the question of the long term vision for LArSoft projecting out to the 2025 era. The project believes this would be a useful discussion, and invites suggestions from the offline leads as to how we might approach the question. One could imagine holding a half-day workshop, for instance, to discuss ideas and issues. Such a discussion is timely given the current work exploring how the HEP computing ecosystem will evolve driven primarily by forces from HL-LHC, along with the continuing evolution of computing architectures. 
5. Regarding the issue of can NumPy and SciPy have standard, LArSoft compatible distributions made available, Mu2e has written a request for this,  19944. In response, python_tools v1_02_00, which includes numpy v_14_3 and scipy v1_1_0, is available in the following builds:
   1. e15 for SLF6 and SLF7
   2. e17 for SLF6 and SLF7
   3. c2 for SLF6, SLF7, Sierra, and High Sierra

DUNE – Andrew John Norman, Heidi Schellman, Tingjun Yang

• We discovered a problem with the simulation of atmospheric neutrinos in the DUNE far detector. This was fixed by Robert Hatcher in nutools v2_21_04 which is incorporated into larsoft v06_78_00. We still need to update the atmospheric neutrino flux driver to account for the orientation of the DUNE far detector. This is work in progress: 20034.
• We are testing a new mode in PMA track reconstruction using the newly available SpacePointSolver. This mode improves the speed of PMA reconstruction by a factor of 2 for ProtoDUNE. The initial test looks promising. More details in 19937.

ICARUS – Daniele Gibin

• No Report

LArIAT – Jonathan Asaadi

• No Report

MicroBooNE – Herbert Greenlee, Tracy Usher

• A partial and somewhat MicroBooNE-specific, but backward compatible, LArG4 refactoring was included in larsoft v06_76_00.  We expect that this refactoring will be superseded by the eventual full refactoring mentioned by Erica above. The important thing is to maintain compatibility with the newly introduced SimEnergyDeposit data product.  For MCC9, the modeling of electron drift, including the effect of induced charge, will be handled outside of larsoft, by the wire cell package.
• The MicroBooNE offline coordinators are not many getting requests for supporting external products.  We know that some people are using numpy and scipy, so MicroBooNE would be supportive of including these in the standard larsoft distribution.  We believe that people who currently use these have figured out how to obtain them outside of larsoft.
• MicroBooNE also has a python/gallery event display that some people use, which is dependent on the external products Qt and PyQt to provide the gui.  The MicroBooNE collaborator who has been providing unofficial support for these external products has stopped doing that, so it will be difficult for users to keep using this event display.

SBND – Roxanne Guenette, Andrzej Szelc

• We have not yet updated the simulations wrt to the timing simulation problem reported two months ago, as we’re doing offline studies to generally improve it, and once that is done – hopefully in a few weeks we can start to implement the fixed version all together. We have been contacted by Wes about refactorization and its connection to light simulation but have not been able to meet yet.
• In parallel, we have been working on studies that look at effects of misalignment in APAs. Currently this is tailored for SBND geometry as is, and is somewhat hacky, but I have talked to Tingjun who expressed interest on behalf of DUNE in this – we will try to make it more generic and applicable to DUNE soon.
• Ad. NumPy/SciPy  – haven’t had explicit requests for this, but have seen persons using them. So have nothing against it, but not really required yet.
• Ad. Event display, we have so far been using the standard event display with its standard woes. Speeding it up would be extremely welcome.

Open issues:

1. Restructuring of LArG4 – Hans Wenzel and William Seligman continue to work on this. It is being tracked in https://cdcvs.fnal.gov/redmine/issues/14454 We are reporting on this every month and also regularly at LArSoft Coordination meetings.
2. Can NumPy and SciPy have standard, LArSoft compatible distributions made available? See discussion in LArSoft section, and issue 19944. This issue is now closed.

Please email Katherine Lato or Erica Snider for any corrections or additions to these notes.