Astrophysics and Space Science

, Volume 311, Issue 1–3, pp 185–190 | Cite as

Vertical structure of hyper-accreting disks and consequences for gamma-ray burst outflows

  • Elena M. Rossi
  • Philip J. Armitage
  • Tiziana Di Matteo
Original Article


We discuss the physics of the power source for gamma-ray bursts (GRBs). There is a great variety of stellar systems proposed as progenitors of long and short GRBs, but any current model for the engine ultimately involves the formation of a hyper-accreting disk around a newly-formed black hole of a few solar masses. The study of such disks can shed light onto the burst composition and energy content. We present preliminary results from disk vertical structure calculations. These include neutrino transport, a height-dependent determination of the nuclear composition, and a simplified treatment of turbulent mixing. We find that vertical mixing is rapid enough to largely erase compositional gradients, and as a consequence the upper layers of the disk reflect the neutron-rich composition of the midplane close to the black hole. We review the implications of this for the nuclear composition of outflows in GRBs. Our models suggest an increasing role for pairs in the upper regions of the disk, and we speculate that a pair-driven wind could be a significant source of cooling.


Accretion, accretion disks Neutrinos Nuclear reactions, nucleosynthesis, abundances Gamma rays: bursts 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Bahcall, J.N., Meszaros, P.: 5–10 GeV neutrinos from gamma-ray burst fireballs. Phys. Rev. Lett. 85, 1362–1365 (2000) CrossRefADSGoogle Scholar
  2. Balbus, S.A., Hawley, J.F.: Instability, turbulence, and enhanced transport in accretion disks. Rev. Mod. Phys. 70, 1–53 (1998) CrossRefADSGoogle Scholar
  3. Begelman, M.C., Meier, D.L.: Thick accretion disks—self-similar, supercritical models. Astrophys. J. 253, 873–896 (1982) CrossRefADSGoogle Scholar
  4. Bell, K.R., Lin, D.N.C.: Using FU Orionis outbursts to constrain self-regulated protostellar disk models. Astrophys. J. 427, 987–1004 (1994) CrossRefADSGoogle Scholar
  5. Beloborodov, A.M.: Nuclear composition of gamma-ray burst fireballs. Astrophys. J. 588, 931–944 (2003a) CrossRefADSGoogle Scholar
  6. Beloborodov, A.M.: Neutron-fed afterglows of gamma-ray bursts. Astrophys. J. 585, 19–22 (2003b) CrossRefADSGoogle Scholar
  7. Cannizzo, J.K.: The accretion disk limit cycle model: toward an understanding of the long-term behavior of SS Cygni. Astrophys. J. 419, 318 (1993) CrossRefADSGoogle Scholar
  8. Carballido, A., Stone, J.M., Pringle, J.E.: Diffusion coefficient of a passive contaminant in a local MHD model of a turbulent accretion disc. Mon. Not. Roy. Astron. Soc. 358, 1055–1060 (2005) CrossRefADSGoogle Scholar
  9. Chen, W.-X., Beloborodov, A.M.: Neutrino-cooled accretion disks around spinning black holes. Astrophys. J. 657 383–399 (2007) CrossRefADSGoogle Scholar
  10. Derishev, E.V., Kocharovsky, V.V., Kocharovsky, V.V.: The neutron component in fireballs of gamma-ray bursts: dynamics and observable imprints. Astrophys. J. 521, 640–649 (1999) CrossRefADSGoogle Scholar
  11. Di Matteo, T., Perna, R., Narayan, R.: Neutrino trapping and accretion models for gamma-ray bursts. Astrophys. J. 579, 706–715 (2002) CrossRefADSGoogle Scholar
  12. Eichler, D., Livio, M., Piran, T., Schramm, D.N.: Nucleosynthesis, neutrino bursts and gamma-rays from coalescing neutron stars. Nature 340, 126–128 (1989) CrossRefADSGoogle Scholar
  13. Frank, J., King, A., Raine, D.J.: Accretion Power in Astrophysics, 3rd edn. Cambridge University Press, Cambridge (2002) Google Scholar
  14. Fromang, S., Papaloizou, J.: Dust settling in local simulations of turbulent protoplanetary disks. Astron. Astrophys. 452, 751–762 (2006) CrossRefADSGoogle Scholar
  15. Hirose, S., Krolik, J.H., Stone, J.M.: Vertical structure of gas pressure-dominated accretion disks with local dissipation of turbulence and radiative transport. Astrophys. J. 640, 901–917 (2006) CrossRefADSGoogle Scholar
  16. Hubeny, I., Agol, E., Blaes, O., Krolik, J.H.: Non-LTE models and theoretical spectra of accretion disks in Active Galactic Nuclei. III. Integrated spectra for hydrogen-helium disks. Astrophys. J. 533, 710–728 (2000) CrossRefADSGoogle Scholar
  17. Janiuk, A., Perna, R., Di Matteo, T., Czerny, B.: Evolution of a neutrino-cooled disc in gamma-ray bursts. Mon. Not. Roy. Astron. Soc. 355, 950–958 (2004) CrossRefADSGoogle Scholar
  18. Johansen, A., Klahr, H.: Dust diffusion in protoplanetary disks by magnetorotational turbulence. Astrophys. J. 634, 1353–1371 (2005) CrossRefADSGoogle Scholar
  19. Lyutikov, M., Blandford, R.: Electromagnetic outflows and GRBs. Astron. Soc. Pac. Conf. Ser. 312, 449 (2004) ADSGoogle Scholar
  20. Popham, R., Woosley, S.E., Fryer, C.: Hyperaccreting black holes and gamma-ray bursts. Astrophys. J. 518, 356–374 (1999) CrossRefADSGoogle Scholar
  21. Razzaque, S., Meszaros, P.: MeV–GeV emission from neutron-loaded short gamma-ray burst jets. Astrophys. J. 650, 998–1003 (2006) CrossRefADSGoogle Scholar
  22. Rossi, E.M., Beloborodov, A.M., Rees, M.J.: Neutron-loaded outflows in gamma-ray bursts. Mon. Not. Roy. Astron. Soc. 369, 1797–1807 (2006) CrossRefADSGoogle Scholar
  23. Ruffert, M., Janka, H.-T., Takahashi, K., Schaefer, G.: Coalescing neutron stars—a step towards physical models. II. Neutrino emission, neutron tori, and gamma-ray bursts. Astron. Astrophys. 319, 122–153 (1997) ADSGoogle Scholar
  24. Shakura, N.I., Sunyaev, R.A.: Black holes in binary systems. Observational appearance. Astron. Astrophys. 24, 337 (1973) ADSGoogle Scholar
  25. Stanek, K.Z., et al.: Spectroscopic discovery of the supernova 2003dh associated with GRB 030329. Astrophys. J. 591, 17–20 (2003) CrossRefADSGoogle Scholar
  26. Turner, N.J., Willacy, K., Bryden, G., Yorke, H.W.: Turbulent mixing in the outer Solar Nebula. Astrophys. J. 639, 1218–1226 (2006) CrossRefADSGoogle Scholar
  27. Vlahakis, N., Koenigl, A.: Large-scale magnetic fields in GRB outflows: acceleration, collimation, and neutron decoupling. Am. Inst. Phys. Conf. Proc. 727, 282–285 (2004) ADSGoogle Scholar
  28. Woosley, S.E.: Gamma-ray bursts from stellar mass accretion disks around black holes. Astrophys. J. 405, 273–277 (1993) CrossRefADSGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Elena M. Rossi
    • 1
  • Philip J. Armitage
    • 1
    • 2
  • Tiziana Di Matteo
    • 3
  1. 1.JILAUniversity of ColoradoBoulderUSA
  2. 2.Department of Astrophysical and Planetary SciencesUniversity of ColoradoBoulderUSA
  3. 3.Department of PhysicsCarnegie-Mellon UniversityPittsburghUSA

Personalised recommendations