English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We have identified spectral features in the late-time X-ray afterglow of theunusually long, slow-decaying GRB 130925A using NuSTAR, Swift-XRT, and Chandra.A spectral component in addition to an absorbed power-law is required at$>4\sigma$ significance, and its spectral shape varies between two observationepochs at $2\times10^5$ and $10^6$ seconds after the burst. Several models canfit this additional component, each with very different physical implications.A broad, resolved Gaussian absorption feature of several keV width improves thefit, but it is poorly constrained in the second epoch. An additive black bodyor second power-law component provide better fits. Both are challenging tointerpret: the blackbody radius is near the scale of a compact remnant ($10^8$cm), while the second powerlaw component requires an unobserved high-energycutoff in order to be consistent with the non-detection by Fermi-LAT.

X-ray Spectral Components in the Afterglow of GRB 130925A