Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-27T20:59:39.189Z Has data issue: false hasContentIssue false
  • English
  • Français

Protoplanetary disks and hard X-rays

Published online by Cambridge University Press:  21 October 2010

Eric D. Feigelson ,
Philip J. Armitage  and
Konstantin V. Getman
Eric D. Feigelson
Affiliation:
Dept. of Astronomy and Astrophysics, Penn State University, University Park PA 16802
Philip J. Armitage
Affiliation:
JILA, Campus Box 440, University of Colorado, Boulder CO 80309 Dept. of Astrophysical and Planetary Sciences, University of Colorado, Boulder CO 80309
Konstantin V. Getman
Affiliation:
Dept. of Astronomy and Astrophysics, Penn State University, University Park PA 16802
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The physics of protoplanetary disks and the early stages of planet formation is strongly affected by the level of ionization of the largely-neutral gas (Armitage 2009; Balbus 2009). Where the ionization fraction is above some limit around ~ 10−12, the magnetorotational instability (MRI) will ensue and the gas will become turbulent. The presence or absence of disk turbulence at various locations and times has profound implications for viscosity, accretion, dust settling, protoplanet migration and other physical processes. The dominant source of ionization is very likely X-rays from the host star (Glassgold et al. 2000). X-ray emission is elevated in all pre-main sequence stars primarily due to the magnetic reconnection flares similar to, but much more powerful and frequent than, flares on the surface of the contemporary Sun (Feigelson et al. 2007).

Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 5 , Highlights H15: Highlights of Astronomy , November 2009 , pp. 744
Copyright
Copyright © International Astronomical Union 2010

References

Armitage, P. 2009, Astrophysics of Planet Formation (Cambridge)CrossRefGoogle Scholar
Balbus, S. A. 2009 in: Garcia, P., (ed.), Physical Processes in Circumstellar Disks Around Young Stars (Chicago)Google Scholar
Feigelson, E., Townsley, L., Güdel, M., & Stassun, K. 2007 in: Reipurth, B. et al. (eds.), Protostars and Planets V (Arizona), p. 313Google Scholar
Getman, K. V., Feigelson, E. D., Broos, P. S., Micela, G., & Garmire, G. P. 2008, Astrophys. J. 688, 418CrossRefGoogle Scholar
Glassgold, A. E., Feigelson, E. D., & Montmerle, T. 2000 in: Mannings, V., et al. (eds.), Protostars and Planets IV (Arizona), p. 429Google Scholar
Ilgner, M. & Nelson, R. P. 2006, Astron. Astrophys. 455, 731CrossRefGoogle Scholar