Revisiting SparsifyMargin in sbndcode/LArG4/larg4_services_sbnd.fcl

[sungbinoh]

In today (2025 Oct. 17th)'s SBND First Analysis Tasks Meeting link,
there has been a discussion regarding the sparsifying the true particle trajectory.

In sbndcode/LArG4/larg4_services_sbnd.fcl, we use

sbnd_particle_list_action:
{
  .
  .
  .
  keepGenTrajectories: ["generator", "corsika"]
  .
  .
  .
  SparsifyTrajectories: true
  SparsifyMargin: 0.015
  .
  .
  .
}

that sparsifies simb::MCTrajectory with 1.5 cm margin that is about 50 times bigger than the original sampling distance.
It is being done in same way for the generator and corsika particles.

Joseph Z. has suggested that revisiting the margin value would be beneficial for the SBND 2025 Fall production.

Please note that energy deposition (edepsim) information is not sparsified.

I'm submitting a ...

• bug report
• feature request

Checklist

• I've added at least 1 label under Labels
• Assigned a reviewer under Assignees

Expected Behavior

Current Behavior

Possible Solution (optional)

How to reproduce