CPPsim

Introduction

CPPsim is a GEANT4 simulation used for the Charged Pion Polarizability experiment in Hall-D. It is maintained as a separate project from the standard Hall-D simulation packages hdgeant and HDGeant4. It does, however, depend on the same [HDDS https://github.com/JeffersonLab/hdds] package for specifying the geometry in Hall-D as well as the sim-recon software suite for things such as the magnetic field map, Lorentz deflections tables, and HDDM I/O.

Quick Start

1. Get a working version of sim-recon and make sure your environment is setup to use it
2. Make sure your ROOT version has gdml support enabled.
   • This is technically not needed if you have a cpproot.gdml available (check if $HDDS_HOME/$BMS_OSNAME/src/cpproot.gdml exists since if it is, then you're good to go)
   • If cpproot.gdml is not in the $HDDS_HOME/$BMS_OSNAME/src then you'll have to find a copy or recompile ROOT to generate one from the HDDS xml source. Configure ROOT using the "-enable-gdml" flag before reconpiling. Then you'll have to go back to step 1.
3. Get a working version of GEANT4 10.02p1 or greater and set your environment up to use it.
   • Here are the lines used on my MBP:
   • > setenv G4 /usr/local/geant4/geant4.10.02p1.Darwin_macosx10.11-x86_64-llvm7.3.0
   • > source $G4/bin/geant4.csh $G4/bin
   • > source $G4/share/Geant4-10.*/geant4make/geant4make.csh $G4/share/Geant4-10.*/geant4make/
4. Checkout CPPsim from subversion and build it via:

   > svn co https://halldsvn.jlab.org/repos/trunk/Experiments/PionPolarizability/src/CPPsim

   > mkdir CPPsim-build

   > cd CPPsim-build

   > ../CPPsim/run_cmake

   > make -j8

   n.b. GEANT4 requires a recent version of cmake. (e.g. for Mac OS X I downloaded and installed 3.4.1 and used the command line executable in /Applications/CMake 3.4.1.app/Contents/bin/cmake)

5. Copy the control.in file from the CPPsim source directory to your working directory and modify to suit your job. This is a well commented file that should guide you through the options.
6. Run CPPsim that was left in the CPPsim-build directory with the "-h" option to see what options are available. No options will just run it using options from the control.in file.
   • n.b. CPPsim will automatically try running any file named "vis,mac" in the current working directory so if you don't want this, make sure that file is not there or use the -nv option when running CPPsim