ohassn / epic

DD4hep Geometry Description of the EPIC Experiment

Overview

The EPIC Detector at IP6 for Electron-Ion Collider experiment.

Detector geometry viewer:

• Central detector
• Full Detector (including beamline)
• Inner detector (without calorimetry)
• Subsystem views:
  • Calorimetry
  • PID
    • dRICH
    • pfRICH
    • DIRC
    • ToF
  • Tracking
    • Vertex detector
  • Far-forward

Browse latest

Detector views

Constants listing

Getting Started

You will likely want to use this repository along with the IP6 repository:

git clone https://github.com/eic/epic.git
git clone https://github.com/eic/ip6.git
ln -s ../ip6/ip6 epic/ip6

Compilation

To configure, build, and install the geometry (to the install directory), use the following commands:

cmake -B build -S . -DCMAKE_INSTALL_PREFIX=install
cmake --build build
cmake --install build

To load the geometry, you can use the scripts in the install directory:

source install/setup.sh

or

source install/setup.csh

Adding/changing detector geometry

Hint: Use the CI/CD pipelines.

To avoid dealing with setting up all the dependencies, we recommend using the continuous integration/continuous deployment (CI/CD) pipelines to make changes and assess their effects. Any feedback to help this process is appreciated.

Here is how to begin:

1. Look at existing detector constructions and reuse if possible. Note that "compact detector descriptions" -> xml files, and "detector construction" -> cpp file.
2. Modify xml file or detector construction.
3. Create a WIP (or draft) merge request or pull request and look at the CI output for debugging. Then go to back to 2 if changes are needed.
4. Remove the WIP/Draft part of the merge request if you would like to see your changes merged into the main.

See:

• Talk at computing round table

Compiling (avoid it)

First, see if the use case above is best for you. It most likely is and can save a lot of time for newcomers. To run the simulation locally, we suggest using the singularity image. More details can be found at the links below:

• https://dd4hep.web.cern.ch/dd4hep/page/beginners-guide/
• https://eic.phy.anl.gov/tutorials/eic_tutorial/
• https://eicweb.phy.anl.gov/containers/eic_container/

Related useful links

• EIC tutorial
• DD4hep repository
• DD4hep user manual