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Detection of ionized gas in the globular cluster 47 Tucanae

P. C. Freire·M. Kramer·A. G. Lyne·F. Camilo·R. N. Manchester·N. D'Amico
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Abstract

We report the detection of ionized intracluster gas in the globular cluster 47 Tucanae. Pulsars in this cluster with a negative period derivative, which must lie in the distant half of the cluster, have significantly higher measured integrated electron column densities than the pulsars with a positive period derivative. We derive the plasma density within the central few pc of the cluster using two different methods which yield consistent values. Our best estimate of n_e = (0.067+-0.015)/cm^3 is about 100 times the free electron density of the ISM in the vicinity of 47 Tucanae, and the ionized gas is probably the dominant component of the intracluster medium.

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P. C. Freire, M. Kramer, A. G. Lyne, F. Camilo, R. N. Manchester, N. D'Amico. 2001-07-11. Detection of ionized gas in the globular cluster 47 Tucanae. https://doi.org/10.1086/323248

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