Eta3PiDalitz

Code for unbinned maximum likelihood fit for Eta->Pi+Pi-Pi0 Dalitz Plot analysis for GlueX Collaboration. Based on AmpTools: https://github.com/mashephe/AmpTools

Contents

• batch_run/ - Scripts for running a batch job using HTCondor
• DalitzAmp/ - Decay amplitude model for AmpTools
• DalitzDataIO - Data handling for AmpTools
• DalitzExe/ - Programs.
• DalitzPlot/ - Generating Dalitz plots from the Decay amplitude model and data
• macros - ROOT and bash macros for event selection, plotting, running the fits, etc.
• run/ - Run directory.

Instructions for running the code

1. Clone the repository
2. Compile the code using make
3. cd into DalitzExe, then compile the executables using make

Running a single fit

1. cd into macros, edit Eta3PiRecosntruction.C to set up the user configuration.
2. run the macro using root -l -b -q Eta3PiReconstruction.C(<options>) to generate flat root tree with the reconstructed events for AmpTools.
3. Write a config file for AmpTools, see the example in run/cfg/*template.cfg.
4. Run the fit using DalitzExe/fitAmplitudes.exe <config file>, the fit results (a .fit file) will be saved in the working directory.
5. It is encouraged for the user to run into AmpTools fit tutorial before doing the fit using this code.

Data format

The data input format for Eta3PiReconstruction.C can be seen at printTree.txt. The data format for AmpTools can be seen at DalitzDataIO/README.md.

Notes

• The code is still under development, please contact the author for any questions.