A Study on anisotropy of cosmic ray distribution with a small array of water-cherenkov detectors

TL;DR

This paper investigates the anisotropy in cosmic ray arrival directions using a small water Cherenkov detector array, revealing anisotropic flow along Galactic arms based on over a million recorded events.

Contribution

It presents a novel measurement of cosmic ray anisotropy using a compact detector array in Tehran, highlighting anisotropic flow aligned with Galactic structures.

Findings

Detected anisotropy along Galactic arms

Recorded over 1.1 million cosmic ray events

Observed anisotropy beyond Earth's motion effects

Abstract

The study of the anisotropy of the arrival directions is an essential tool to investigate the origin and propagation of cosmic rays primaries. A simple way of recording many cosmic rays is to record coincidences between a number of detectors. We have monitored multi-TeV cosmic rays by a small array of water cherenkov detectors in Tehran(35 43 N, 51 20 E, 1200m a.s.l). More than 1.1*10^6 extensive air shower events were recorded. In addition to the Compton- Getting effect due to the motion of the earth in the Galaxy, an anisotropy has been observed which is due to a unidirectional anisotropy of cosmic ray flow along the Galactic arms.