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تسجيل مستخدم جديدDetection of ionized gas in the globular cluster 47 Tucanae
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P. C. Freire
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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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