# Instrumentation for Colliding Beam Physics (INSTR-17)

27 February 2017 to 3 March 2017
Budker Institute of Nuclear Physics
Asia/Novosibirsk timezone

## Separation of e+e- to e+e- and e+e- to pi+pi- events based on the difference in the energy deposition profiles in SND detector calorimeter.

28 Feb 2017, 17:00
1h
Budker Institute of Nuclear Physics

#### Budker Institute of Nuclear Physics

11, akademika Lavrentieva prospect, Novosibirsk, Russia
Board: 25
Poster Particle identification

### Speaker

Mr Andrey Kupich (BINP)

### Description

The technique of discrimination of the $e^+e^-\to e^+e^-$ and $e^+e^-\to \pi^+\pi^-$ events in energy range $0.5 < \sqrt{s} < 1$ GeV based on the difference in the energy deposition in calorimeter of SND detector was developed by applying machine learning method. In particular the following parameters are used: $^0E_{j}$ is the energy deposition in $j$th layer of the tower with the maximal energy deposition, $^1E_{j}$ is the sum of energy depositions in $j$th layer of eight towers that surround the tower with the maximal energy deposition, $^2E_{j}$ is the sum of energy depositions in $j$th layer of the other towers of the cluster ($j=1,2,3$).Identification efficiency for $e^+e^-\to e^+e^-$ and $e^+e^-\to \pi^+\pi^-$ events is estimated to be in the range from 99.3 to 99.8 %. Contribution of the identification efficiencies errors to the total error of $e^+e^-\to\pi^+\pi^-$ cross section is less than 0.2% for the most energy points.

### Primary author

Mr Andrey Kupich (BINP)

### Presentation Materials

There are no materials yet.