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High resolution Chandra X-ray imaging of the nucleus of M33

G. Dubus·P. A. Charles·K. S. Long
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Abstract

We show with a short Chandra HRC-S exposure that the powerful X-ray source coincident with the nucleus of M33 is unresolved at the highest spatial resolution available to date (0"4). The source flux is variable, doubling during the 5 ks exposure. The combination of properties exhibited by M33 X-8 establishes the source as the nearest example of the ultra-luminous X-ray sources that have been uncovered in other nearby galaxies. On short timescales, we set limits of 9% r.m.s. variability for pulsations in the 0.01-1000 Hz range.

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G. Dubus, P. A. Charles, K. S. Long. 2004-06-14. High resolution Chandra X-ray imaging of the nucleus of M33. https://doi.org/10.1051/0004-6361%3A20041253

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