Kα iron line profile from accretion disks around regular and singular exotic compact objects

Cosimo Bambi, Daniele Malafarina

Research output: Contribution to journalArticlepeer-review

62 Citations (Scopus)


The nature of the supermassive black hole candidates in galactic nuclei can be tested by analyzing the profile of the Kα iron line observed in their x-ray spectrum. In this paper, we consider the possibility that the spacetime in the immediate vicinity of these objects may be described by some nonvacuum exact solutions of Einstein's equations resulting as the end state of gravitational collapse. The vacuum far away portion of the spacetime is described by the Schwarzschild metric, while the interior part may be either regular or have a naked singularity at the center. The iron line generated around this class of objects has specific features, which can be used to distinguish such objects from Kerr black holes. In particular, their iron line cannot have the characteristic low-energy tail of the line generated from accretion disks around fast-rotating Kerr black holes. We can thus conclude that the supermassive black hole candidates whose spin parameter has been estimated to be close to 1 assuming the Kerr background cannot be this kind of objects.

Original languageEnglish
Article number064022
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Issue number6
Publication statusPublished - Sep 10 2013

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Physics and Astronomy (miscellaneous)

Fingerprint Dive into the research topics of 'Kα iron line profile from accretion disks around regular and singular exotic compact objects'. Together they form a unique fingerprint.

Cite this