Muon study for gamma/hadron air-shower discrimination in the HAWC observatory

40th Symposium on Nuclear Physics 2017

Zuñiga Reyes, A.^1 ; Hernández Almada, A.^1,2 ; Sandoval Espinosa, A.^1

Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20364, México D.F

01000, Mexico^1

Facultad de Ingeniería, Universidad Autónoma de Querétaro, Centro Universitario, Cerro de las Campanas, Santiago-de-Querétaro

76010, Mexico^2

关键词: Air showers;    Characteristic time;    Cherenkov;    Ground based;    High presences;    Time-differences;    Water Cherenkov detectors;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/876/1/012023/pdf
DOI  :  10.1088/1742-6596/876/1/012023

来源: IOP

【 摘 要 】

The High-Altitude Water Cherenkov observatory is a ground-based array designed to study energetic gamma-rays. Experiments with this purpose have to face a huge rate of undesired hadronic background. Motivated by the fact that muon content is quite different in gamma-induced (poor in muons) and hadronic-induced (rich in muons) air-showers, we study the idea of formulating a new variable for background reduction related with counting the number of muons candidates present in such showers. Therefore, in this work we used the time differences between photomultipliers tubes to identify the signature of muons inside the water Cherenkov detectors. Showers with a high presence of muons typically must produce a characteristic time difference around 5 ns among the central detector (PMT-C) and each one of the laterals (PMT: A, B, D).