Latest news from the HAWC outrigger array

TL;DR

The paper reports on the recent upgrade of the HAWC gamma-ray observatory with an outrigger array, enhancing its sensitivity and reconstruction capabilities for high-energy cosmic sources.

Contribution

It presents the design, implementation, and initial results of the HAWC outrigger array, a significant upgrade to improve detection of high-energy gamma rays.

Findings

Enhanced reconstruction of air showers with the outrigger array

Increased effective area for gamma-ray detection above a few TeV

First performance results demonstrating improved sensitivity

Abstract

The High Altitude Water Cherenkov (HAWC) observatory is a very high energy gamma-ray detector located in Mexico. In late 2018, the HAWC collaboration completed a major upgrade consisting of the addition of a sparse outrigger array of 345 small water Cherenkov detectors (WCDs) surrounding the 300 WCDs of the main array and extending the instrumented area by a factor of 4. It provides an improved reconstruction of the showers whose core and footprint are not well contained in the array and increases the effective area in the range of a few TeV to beyond 100 TeV. This improvement in sensitivity will help to have a better understanding of the Galactic sources that accelerate particles up to the knee of the cosmic ray spectrum. In this contribution, we will show the current status, the performance, and the first results from the HAWC outrigger array.