Book contents
- Frontmatter
- Contents
- Foreword
- Acknowledgments
- Introduction
- Notation
- 1 Superluminal motion in the quasar 3C273
- 2 Curved spacetime and SgrA*
- 3 Parallel transport and isometry of tangent bundles
- 4 Maxwell's equations
- 5 Riemannian curvature
- 6 Gravitational radiation
- 7 Cosmological event rates
- 8 Compressible fluid dynamics
- 9 Waves in relativistic magnetohydrodynamics
- 10 Nonaxisymmetric waves in a torus
- 11 Phenomenology of GRB supernovae
- 12 Kerr black holes
- 13 Luminous black holes
- 14 A luminous torus in gravitational radiation
- 15 GRB supernovae from rotating black holes
- 16 Observational opportunities for LIGO and Virgo
- 17 Epilogue: GRB/XRF singlets, doublets? Triplets!
- Appendix A Landau's derivation of a maximal mass
- Appendix B Thermodynamics of luminous black holes
- Appendix C Spin–orbit coupling in the ergotube
- Appendix D Pair creation in a Wald field
- Appendix E Black hole spacetimes in the complex plan
- Appendix F Some units, constants and numbers
- References
- Index
14 - A luminous torus in gravitational radiation
Published online by Cambridge University Press: 17 August 2009
- Frontmatter
- Contents
- Foreword
- Acknowledgments
- Introduction
- Notation
- 1 Superluminal motion in the quasar 3C273
- 2 Curved spacetime and SgrA*
- 3 Parallel transport and isometry of tangent bundles
- 4 Maxwell's equations
- 5 Riemannian curvature
- 6 Gravitational radiation
- 7 Cosmological event rates
- 8 Compressible fluid dynamics
- 9 Waves in relativistic magnetohydrodynamics
- 10 Nonaxisymmetric waves in a torus
- 11 Phenomenology of GRB supernovae
- 12 Kerr black holes
- 13 Luminous black holes
- 14 A luminous torus in gravitational radiation
- 15 GRB supernovae from rotating black holes
- 16 Observational opportunities for LIGO and Virgo
- 17 Epilogue: GRB/XRF singlets, doublets? Triplets!
- Appendix A Landau's derivation of a maximal mass
- Appendix B Thermodynamics of luminous black holes
- Appendix C Spin–orbit coupling in the ergotube
- Appendix D Pair creation in a Wald field
- Appendix E Black hole spacetimes in the complex plan
- Appendix F Some units, constants and numbers
- References
- Index
Summary
Alice laughed: “There's no use trying,” she said; “one ca'n't believe impossible things.” “I daresay you haven't had much practice,” said the Queen. “When I was your age, I always did it for half-an-hour a day. Why, sometimes I've believed as many as six impossible things before breakfast.”
Lewis Carroll, Through the Looking-glass, and what Alice Found There, Chapter 5.A torus surrounding a luminous black hole receives black hole spin energy for reprocessing in various emission channels. A balance between spin energy received and energy radiated allows a torus to remain in place for the duration of rapid spin of the black hole – a suspended accretion state[569]. Amplification of this “seed” field to superstrong values requires a dynamo action in the torus. Conceivably, this dynamo is powered by black hole-spin energy in a long-lasting suspended accretion state.
In this chapter, we derive a bound on the magnetic field energy that a torus of given mass can support. It defines a black hole luminosity function in terms of the angular velocity and mass of the torus, both relative to the angular velocity and mass of the black hole. The torus is compact and lives around a stellar mass black hole. The competing torques of spin-up by the black hole and spin-down by radiation promote a slender shape. This raises the questions: What is the lifetime of rapid spin of the black hole and its luminosity? What are the radiation energies emitted by the torus?
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- Publisher: Cambridge University PressPrint publication year: 2005