# Welcome to NICA days 2019 and IVth MPD Collaboration Meeting in Warsaw

Oct 21 – 25, 2019
CZiITT
Europe/Warsaw timezone

## Convolutional neural network for centrality determination in fixed target experiments

Oct 22, 2019, 5:25 PM
25m
Conference room... (CZiITT)

### Conference room...

#### CZiITT

Centrum Zarządzania Innowacjami i Transferem Technologii Politechniki Warszawskiej cziitt@pw.edu.pl ul. Rektorska 4 00-614 Warszawa
NICA and NA61/SHINE joint session

### Speaker

Denis Uzhva (St Petersburg State University (RU))

### Description

Fixed target experiments have an unique possibility to measure centrality of colliding systems by hadronic calorimeters on the beam line. This is usually achieved by the detection of all forward nucleon spectators and accomplishes fluctuation and correlation measures with lower biases than in collider experiments. However, hadronic calorimeters have much lower resolution than multiplicity detectors that introduces additional volume fluctuation to the measures.
In this work, we present the first attempt to increase the resolution capacity of the spectator detector by implementing a convolutional neural network to the modular structure of the Projectile Spectator Calorimeter of the NA61/SHINE experiment. The data were generated in the framework of SHIELD Monte-Carlo event generator with detector response simulated with GEANT4 for the collisions of the lightest available system (${}^7$Be+${}^9$Be) and for the highest beam momentum (150A GeV/c). Two ways of determination centrality -- by a number of forward spectators and by forward energy -- are considered. In comparison with the classical centrality selection method, the neural net shows a significant increase of centrality selection accuracy after implementation.

### Primary author

Denis Uzhva (St Petersburg State University (RU))

### Co-author

Andrey Seryakov (St Petersburg State University (RU))

### Presentation materials

 20191022 Seryakov CNN for centrality.pdf 20191022 Seryakov CNN for centrality.pptx