Detection of extended TeV emission around the Geminga pulsar with H.E.S.S

TL;DR

This paper reports the detection of highly extended TeV gamma-ray emission around the Geminga pulsar using H.E.S.S., overcoming previous observational challenges with new analysis techniques and adapted strategies.

Contribution

It presents the first independent detection of extended TeV emission around Geminga with H.E.S.S., demonstrating advanced analysis methods for large-scale gamma-ray observations.

Findings

Detection of significant TeV emission around Geminga in independent data

Implementation of new analysis techniques for extended gamma-ray sources

Discussion of technical challenges in observing large-scale gamma-ray emission

Abstract

Highly extended gamma-ray emission around the Geminga pulsar was discovered by Milagro and verified by HAWC. Despite many observations with Imaging Atmospheric Cherenkov Telescopes (IACTs), detection of gamma-ray emission on angular scales exceeding the IACT field-of-view has proven challenging. Recent developments in analysis techniques have enabled the detection of significant emission around Geminga in archival data with H.E.S.S.. In 2019, further data on the Geminga region were obtained with an adapted observation strategy. Following the announcement of the detection of significant TeV emission around Geminga in archival data, in this contribution we present the detection in an independent dataset. New analysis results will be presented, and emphasis given to the technical challenges involved in observations of highly extended gamma-ray emission with IACTs.