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Shadows of Kerr black holes with and without scalar hair. (English) Zbl 1347.83020

Summary: For an observer, the Black Hole (BH) shadow is the BHs apparent image in the sky due to the gravitational lensing of nearby radiation, emitted by an external source. A recent class of solutions dubbed Kerr BHs with scalar hair possess smaller shadows than the corresponding Kerr BHs and, under some conditions, novel exotic shadow shapes can arise. Thus, these hairy BHs could potentially provide new shadow templates for future experiments such as the Event Horizon Telescope. In order to obtain the shadows, the backward ray-tracing algorithm is briefly introduced, followed by numerical examples of shadows of Kerr BHs with scalar hair contrasting with the Kerr analogues. Additionally, an analytical solution for the Kerr shadow is derived in closed form for a ZAMO observer at an arbitrary position.

MSC:

83C57 Black holes
83B05 Observational and experimental questions in relativity and gravitational theory

References:

[1] 1. R. P. Kerr, Phys. Rev. Lett.11 (1963) 237. genRefLink(16, ’S0218271816410212BIB001’, ’10.1103
[2] 2. D. Robinson, The Kerr Spacetime: Rotating Black Holes in General Relativity, eds. D. Wiltshire et al., (Cambridge University Press, Cambridge, England, 2009).
[3] 3. H. Falcke, F. Melia and E. Agol, Astrophys. J.528 (2000) L13. genRefLink(16, ’S0218271816410212BIB003’, ’10.1086
[4] 4. T. Johannsen, arXiv:1512.03818 [astro-ph.GA].
[5] 5. P. V. P. Cunha, C. A. Herdeiro, E. Radu and H. F. Rúnarsson, Phys. Rev. Lett.115 (2015) 211102. genRefLink(16, ’S0218271816410212BIB005’, ’10.1103
[6] 6. P. V. P. Cunha, Black hole shadows, Master Thesis, University of Coimbra (2015).
[7] 7. T. Johannsen, Astrophys. J.777 (2013) 170. genRefLink(16, ’S0218271816410212BIB007’, ’10.1088
[8] 8. J. M. Bardeen, Timelike and null geodesies in the Kerr metric, in Proc., Ecole d’Eté de Physique Théorique: Les Astres Occlus, eds. C. Witt and B. Witt (Les Houches, France, 1973), p. 215.
[9] 9. V. P. Frolov and I. D. Novikov (eds.), Black Hole Physics: Basic Concepts and New Developments (Kluwer Academic Publishers, 1998). genRefLink(16, ’S0218271816410212BIB009’, ’10.1007 · Zbl 0978.83001
[10] 10. O. James, E. von Tunzelmann, P. Franklin and K. S. Thorne, Class. Quantum Grav.32 (2015) 065001. genRefLink(16, ’S0218271816410212BIB010’, ’10.1088
[11] 11. J. L. Jaramillo and E. Gourgoulhon, Mass and angular momentum in general relativity, in Mass and Motion in General Relativity (Springer, Netherlands, 2009), p. 87. genRefLink(16, ’S0218271816410212BIB011’, ’10.1007 · Zbl 1213.83060
[12] 12. B. Carter, Phys. Rev.174 (1968) 1559. genRefLink(16, ’S0218271816410212BIB012’, ’10.1103
[13] 13. S. Chandrasekhar (eds.), The Mathematical Theory of Black Holes (Oxford Classic Texts in the Physical Sciences, Clarendon Press, UK, 1998).
[14] 14. C. A. Herdeiro and E. Radu, Phys. Rev. Lett.112 (2014) 221101. genRefLink(16, ’S0218271816410212BIB014’, ’10.1103
[15] 15. C. A. Herdeiro and E. Radu, Class. Quantum Grav.32 (2015) 144001. genRefLink(16, ’S0218271816410212BIB015’, ’10.1088
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