Chandra detection of a new diffuse X-ray component from the globular cluster 47 Tucanae

TL;DR

This study re-analyzed Chandra data of 47 Tucanae, revealing a new diffuse X-ray component with both thermal and non-thermal features, likely caused by stellar wind shocks and pulsar wind interactions.

Contribution

It is the first detection of a diffuse X-ray emission component in 47 Tucanae, combining thermal plasma and non-thermal emission, explained by stellar wind shocks and pulsar wind interactions.

Findings

Detected diffuse X-ray emission within 47 Tucanae

Spectral analysis shows thermal and non-thermal components

Non-thermal emission decreases exponentially from the core

Abstract

In re-analyzing the archival Chandra data of the globular cluster 47 Tucanae, we have detected a new diffuse X-ray emission feature within the half-mass radius of the cluster. The spectrum of the diffuse emission can be described by a power-law model plus a plasma component with photon index $\Gamma\sim1.0$ and plasma temperature $kT\sim0.2$ keV. While the thermal component is apparently uniform, the non-thermal contribution falls off exponentially from the core. The observed properties could possibly be explained in the context of multiple shocks resulted from the collisions among the stellar wind in the cluster and the inverse Compton scattering between the pulsar wind and the relic photons.