Antineutron Reconstruction and Identification in Electromagnetic Calorimeter

Abstract

The ALICE experiment at the LHC is designed to explore the hot and dense medium produced in heavy-ion collisions, the so-called quark–gluon plasma (QGP). Antineutron production is a poorly explored domain of high energy physics, although it is interesting in the context of hadrons decaying into antineutrons, the interaction of antineutrons with hadrons, and searching for bound states of antineutrons. We present a method for measuring antineutrons by the electromagnetic calorimeter PHOS of the ALICE experiment. An antineutron can be identified by the cluster shape and the energy deposition in the calorimeter, and its momentum can be reconstructed using the time-of-flight information. The proposed method was verified via the reconstruction of $\bar{\Sigma}^{\pm}$ through decays $\bar{\Sigma}^{+}\rightarrow\bar{n}\pi^{+}$ and $\bar{\Sigma}^{-}\rightarrow\bar{n}\pi^{-}$ with an antineutron identified in the PHOS.