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The discovery of quiescent X-ray emission from SAX J1808.4-3658, the transient 2.5ms pulsar

L. Stella·S. Campana·S. Mereghetti·D. Ricci·G. L. Israel
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Abstract

We report on a 20 ks BeppoSAX observation of the transient 2.5 ms X-ray pulsar SAX J1808.4-3658 in its quiescent state. A source at a level of ~ 3 x 10^-3 c/s was detected with the BeppoSAX/MECS at a position consistent with that of SAX J1808.4-3658. The inferred 0.5-10 keV luminosity was to that measured from other quiescent low mass X-ray transients hosting an old neutron star. This result is discussed in the light of the propeller and radio pulsar shock emission models for the quiescent emission of these systems.

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L. Stella, S. Campana, S. Mereghetti, D. Ricci, G. L. Israel. 2000-05-22. The discovery of quiescent X-ray emission from SAX J1808.4-3658, the transient 2.5ms pulsar. https://doi.org/10.1086/312765

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