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

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 نشر من قبل Chung Yue Hui David
 تاريخ النشر 2014
  مجال البحث فيزياء
والبحث باللغة English
 تأليف E. M. H. Wu




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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 $Gammasim1.0$ and plasma temperature $kTsim0.2$ 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.



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