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arXiv · 1001.1855

Detection of High-Energy Gamma-Ray Emission from the Globular Cluster 47 Tucanae with Fermi

N. A. Webb·J. Knödlseder
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Abstract

Globular clusters are known to harbour a significant population of neutron star X-ray binaries that could be responsible for delaying the inevitable core collapse of these dense clusters. As a result, their progeny, namely millisecond pulsars, are also present in large numbers. Following the confirmation using the Fermi Gamma-ray Space Telescope that millisecond pulsars are indeed gamma-ray emitters, we report on the detection of the Galactic globular cluster 47 Tuc with the Fermi Large Area Telescope. This is the first detection of a Galactic globular cluster in the gamma-ray domain. The gamma-ray spectrum is consistent with gamma-ray emission from a population of millisecond pulsars. The observed gamma-ray luminosity implies an upper limit of 60 millisecond pulsars present in 47 Tucanae.

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N. A. Webb, J. Knödlseder. 2010-01-12. Detection of High-Energy Gamma-Ray Emission from the Globular Cluster 47 Tucanae with Fermi. https://arxiv.org/abs/1001.1855

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