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Results are presented from a 500ks long XMM-Newton observation of theNarrow-Line Seyfert 1 galaxy IRAS13224-3809. The source is rapidly variable ontimescales down to a few 100s. The spectrum shows strong broad Fe-K and Lemission features which are interpreted as arising from reflection from theinner parts of an accretion disc around a rapidly spinning black hole. Assuminga power-law emissivity for the reflected flux and that the innermost radiuscorresponds to the innermost stable circular orbit, the black hole spin ismeasured to be 0.988 with a statistical precision better than one per cent.Systematic uncertainties are discussed. A soft X-ray lag of 100s confirms thisscenario. The bulk of the power-law continuum source is located at a radius of2-3 gravitational radii.

Long XMM observation of the Narrow-Line Seyfert 1 galaxy IRAS13224-3809: rapid variability, high spin and a soft lag