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Unexpected X-ray flares

Two sources of highly energetic flares have been discovered in archival X-ray data of 70 nearby galaxies. These flares have an undetermined origin and might represent previously unknown astrophysical phenomena. See Letter p.356

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Figure 1: The environment of Centaurus A.

NASA/CXC/Univ. Birmingham/M. Burke et al.


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Correspondence to Sergio Campana.

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Campana, S. Unexpected X-ray flares. Nature 538, 321–322 (2016).

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