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playground:benedetta_m_pietrobono2021

# Muon detection in electron-positron annihilation for muon collider studies

## Introduction

The LEMMA project [4] aims to study the possibility of producing muons from the ${e^+}{e^-}$ annihilation process. A high intensity positron beam, with energy just above the 43.7 GeV threshold for muon pair production through the ${e^+}{e^-}\rightarrow{µ^+}{µ^-}$ process, impinging on a low ${Z}$ fixed target [5] could produce muons with naturally small divergence, resulting in a low transverse emittance

## Tracker- absorbers correlation

As a first step, this analysis studied the relation between the particle’s $x$ position measured by the tracker positioned before the first scintillator of the negative arm and the energy released E3 in the central LG unit. Fig. 3 shows the average electron (muon) released energy $\left \langle E_3 \right \rangle$ in the central LG unit in blue (green), as a function of the x position measured by the tracker.

## HOrizontal Smart Absorber efficiency

The efficiency of each HORSA active layer has been studied using a muon beam with energy $E^0$. The efficiency of each HORSA active layer $j = 5,6,7,8$ is defined as: $$\varepsilon_j=\frac{N_4}{N_3(j)}$$ where $N_4$ represents the number of events with signals in time coincidence in all four layers while $N_3(j)$ represents the number of events with signals in time coincidence in all the layers but the $j$ one. The overall efficiency of the HORSA absorber is defined as $$\varepsilon_\text{HORSA}=\prod_{j=5}^{8}\varepsilon_j$$ Results obtained from the run with a muon beam of energy $E_0$ and no target in place are given in Tab. 1, together with the corresponding statistical uncertainties evaluated assuming binomial statistics.

$j$ $\varepsilon_{j}\left(\%\right)$ $\varepsilon_{HORSA}\left(\%\right)$
5$97.04\pm0.56$$84.2\pm1.4$
6$95.50\pm0.66$
7$93.26\pm0.98$
8$97.44\pm0.79$
Table 1: Efficiencies to detect a 22 GeV muon in each of the fused silica HORSA layers together with the overall HORSA efficiency

#### Commento Fausto C.

Qualche imprecisione sull'uso di latex (ad esempio il $\mu$ lo hai scritto utilizzando i caratteri speciali anzichè il codice latex, inoltre non hai scritto la nota che testo e immagini sono presi dall'articolo arxiv:2105.12624 ma comunque va bene. Ti do 1h di lavoro a casa

playground/benedetta_m_pietrobono2021.txt · Ultima modifica: 2022/01/07 08:08 da fausto.casaburo