The Auger@TA Project: Phase II Progress and Plans

Corbin Covault,Takashi Sako,Robert Halliday,Jeffrey Johnsen,Toshihiro Fujii,Fred Sarazin,Sean Quinn,Hiroyuki Sagawa,Ricardo Sato,Ryuji Takeishi,Toshiyuki Nonaka,Ryan Lorek,David Schmidt,I Lhenry-Yvon,J Biteau,P Ghia,O Deligny

doi:10.1051/epjconf/201921005004

Abstract

The Auger@TA project is a combined effort involving members of both the Pierre Auger Observatory and the Telescope Array experiment (TA) to cross-calibrate detectors and compare results on air showers detected at one location. We have recently reported results from Phase I of the project, during which we collected and presented data from two Auger water Cherenkov surface detector stations deployed into the TA experiment near the Central Laser Facility. For Phase II, we will deploy a micro-array of six or seven single-PMT Auger surface detector stations co-located with TA scintillator surface detector stations. The Auger micro-array will trigger and collect data independently from the TA allowing for a complete end-to-end comparison of detector data, calibration, and reconstructed event quantities on a shower-by-shower basis between the TA and Auger detector systems. We describe progress towards development of the micro-array for Phase II including the preparation of surface detector water tanks, station electronics, wireless communications, triggers, and data acquisition. We also outline plans for deploying the Auger@TA micro-array into the TA experiment in 2019 with preliminary estimates for coincident air-shower rates.

Highlights

The Pierre Auger Observatory (Auger) [1] and the Telescope Array (TA) [? ] are the two major observatories for the highest energy cosmic rays
Both Auger and TA are hybrid observatories, combining atmospheric fluorescence telescopes with large arrays of surface detectors sensitive to shower particles arriving at the ground
The primary aspect of Phase I was the deployment of two Auger water Cherenkov detectors (WCD) surface detector stations at the TA Central Laser Facility (CLF)

Summary

Introduction

The Pierre Auger Observatory (Auger) [1] and the Telescope Array (TA) [? ] are the two major observatories for the highest energy cosmic rays. TA is located near Delta, Utah, USA, and views the northern sky Both Auger and TA are hybrid observatories, combining atmospheric fluorescence telescopes with large arrays of surface detectors sensitive to shower particles arriving at the ground. While the Auger and TA all-particle cosmic ray spectra agree up to ≈ 50 EeV, the results begin to diverge at the highest energies [3]. This discrepancy could be due to experimental difference in Auger vs TA that might impact the measurement of cosmic rays. The primary aspect of Phase I was the deployment of two Auger WCD surface detector stations at the TA Central Laser Facility (CLF). Deployment of a micro-array of six or seven Auger WCDs into TA

Overview of Phase I:

Pierre Auger and Telescope Array surface detector stations

Phase II

Conclusions