GSOC 18 Technical description - grasseau/HAhRD GitHub Wiki
Data inputs
The data needs to the CNN classification are in ROOT files (not interesting for our proposal) which contain events (these events are simulated). Each event contains 3D-energy map of energy deposits (or 3D-image) left by a crossing particle or (crossing particles) in hexagonal sensors of the HGCAL detector. The 3D-image contains the 52 planes of HGCAL detector with the position of the sensors with the energy left. Inside one plane, there are two main regions: inner and outer regions inside which there are two different different sensor sizes. As a result the mesh of HGCAL is quite complex, meshes can be considered regular by regions of the detector.
Learning part
We will not learn with the results of the current clustering method. The CNN learning will be carried out with the knowledge of the HGCAL incoming particles: type of the particle, position, energy, and possibly the direction the particles (all this quantities are in the input ROOT file). In addition, some simple synthetic event will be generated to start the learning phase.
Starting code
The starting code is a simple python code, performing a post-processing to analyze the current clustering algorithm. All python tools are in this file to get all data for CNN processing. To run it, please, download it (processing.ipynb) an run with Jupyter notebook or adapt the Jupyter file to simple python file. The path to the input ROOT file must be adjusted.
Vocabulary:
| Suffix/prefix/name used | Definition |
|---|---|
| rechit | a recorded event (energy deposit) in one cell of the detector |
| _x,_y,_z | position (of a hit) |
| _energy | Energy deposit in the cell (sensor) |
| _layer | Layer index (52 layers/plane) |
| _cluster2d | Cluster index found by the current clustering algorithm |
| genpart | Characteristics of the simulated particle (considered as the truth information to learn the CNN) |
| _reachedEE | Particle which reach the HGCAl EE part, meaning that the particle enter in HGCAL |
| _pid | Particle type (photon, electron, ...) |
| _posx,_posy,_posz | position of the HGCAL in-going particle |
| _eta, _phi | Angles of the incident particle |
| pt | Transverse momentum of the particle (projection of the particle momentum on the perpendicular plane of the beam (HGCAL detector axis) |