The Cherenkov Telescope Array Will Test Whether Pulsars Generate the Galactic Center Gamma-Ray Excess

TL;DR

This paper evaluates whether the Cherenkov Telescope Array can detect TeV gamma-ray emission from pulsars to test if they cause the Galactic Center excess, potentially distinguishing between pulsar and dark matter origins.

Contribution

It introduces a template-based analysis using simulated CTA data to assess pulsar contributions to the gamma-ray excess.

Findings

CTA can definitively detect TeV emission from pulsars after brief observations.

Detection or non-detection will test the pulsar hypothesis for the gamma-ray excess.

The method provides a new way to distinguish between dark matter and pulsar explanations.

Abstract

The GeV-scale gamma-ray excess observed from the region surrounding the Galactic Center has been interpreted as either the products of annihilating dark matter particles, or as the emission from a large population of faint and centrally-located millisecond pulsars. If pulsars are responsible for this signal, they should also produce detectable levels of TeV-scale emission. In this study, we employ a template-based analysis of simulated data in an effort to assess the ability of the Cherenkov Telescope Array (CTA) to detect or constrain the presence of this emission, providing a new and powerful means of testing whether millisecond pulsars are responsible for the observed excess. We find that after even a relatively brief observation of the Inner Galaxy, CTA will be able to definitively detect this TeV-scale emission, or rule out pulsars as the source of the Galactic Center Gamma-Ray Excess.