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arXiv · 1112.4974

Discovery of VHE gamma-ray emission from the direction of the globular cluster Terzan 5

W. Domainko·A. -C. Clapson·F. Brun·P. Eger·M. Jamrozy·M. Dyrda·N. Komin·U. Schwanke
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Abstract

Globular clusters are old stellar systems which exhibit very-high stellar densities in their cores. The globular cluster Terzan 5 is characterized by a high stellar encounter rate and hosts the largest detected population of millisecond pulsars. It also features bright GeV gamma-ray emission and extended X-ray radiation. However, no globular clusters have been detected in very-high-energy gamma rays (VHE, E> 100 GeV) so far. In order to investigate this possibility Terzan 5 has been observed with the H.E.S.S. telescope array in this energy band. The discovery of a source of VHE gamma rays from the direction of this globular cluster will be reported. The results of the VHE analysis and a multi-wavelength view of Terzan 5 will be presented in this contribution. No counterpart or model can fully explain the observed morphology of the detected VHE gamma-ray source.

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W. Domainko, A. -C. Clapson, F. Brun, P. Eger, M. Jamrozy, M. Dyrda, N. Komin, U. Schwanke. 2011-12-21. Discovery of VHE gamma-ray emission from the direction of the globular cluster Terzan 5. https://doi.org/10.7529/icrc2011%2Fv07%2F0403

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