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Probing the warm Inter-Galactic Medium through absorption against Gamma Ray Bursts X-ray afterglows

F. Fiore·F. Nicastro·S. Savaglio·L. Stella·M. Vietri
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Abstract

Gamma Ray Burst (GRB) afterglows close to their peak intensity are among the brightest X-ray sources in the sky. Despite their fast power-law like decay, when fluxes are integrated from minutes up to hours after the GRB event, the corresponding number counts (logN-logF relation) far exceeds that of any other high redshift (z>0.5) source, the flux of which is integrated over the same time interval. We discuss how to use X-ray afterglows of GRBs as distant beacons to probe the warm (10^5 K =300) would be very well suited to exploit the new diagnostic and study the physical conditions in the Universe at the critical moment when structure is being formed.

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F. Fiore, F. Nicastro, S. Savaglio, L. Stella, M. Vietri. 2000-09-19. Probing the warm Inter-Galactic Medium through absorption against Gamma Ray Bursts X-ray afterglows. https://doi.org/10.1086/317286

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