Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-26T03:42:10.587Z Has data issue: false hasContentIssue false

The Radiative Impact of FU Orionis Outbursts on Protostellar Envelopes

Published online by Cambridge University Press:  25 May 2016

K. R. Bell
Affiliation:
Space Sciences Division, NASA Ames Research Center MS 245-3 Moffett Field, CA 94035, USA [email protected]
K. M. Chick
Affiliation:
Space Sciences Division, NASA Ames Research Center MS 245-3 Moffett Field, CA 94035, USA [email protected]

Abstract

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.

We present preliminary results of an investigation into the radiative impact of FU Orionis outbursts on protostellar envelopes. In the thermal accretion disk instability model, the inner portion of the disk is inflated in such a way as to funnel most of the outburst luminosity along the poles of the system. A multidimensional radiative transfer code is employed to derive the thermal equilibrium structure of the surrounding protostellar envelope and the backheated accretion disk during outburst. The radiation emitted during outburst is modeled as a combination of a self-luminous accretion disk and a central point source. We compare the relative heating of circumstellar material due to (1) an isotropic point source and (2) an anisotropic point source in which the emitted radiation is confined to a 30° cone about the polar axis. The isotropic point source creates a spherical dust cavity, while the anisotropic source naturally results in a cavity which is hourglass-shaped. Repeated outbursts may ultimately be responsible for the large-scale polar cavities commonly inferred to exist around young stellar objects. We also show that due to the anisotropy of the radiation expected during outburst, disk annuli within a few au will be shielded from the radiation of the outburst.

Type
IV. Disks, Winds, and Magnetic Fields
Copyright
Copyright © Kluwer 1997 

References

Bally, J. & Devine, D. 1994, ApJ, 428, L65.CrossRefGoogle Scholar
Bally, J., Devine, D., Fesen, R. A., & Laine, A. P. 1995, ApJ, 454, 345.CrossRefGoogle Scholar
Bell, K. R. & Lin, D. N. C. 1994, ApJ, 427, 987.CrossRefGoogle Scholar
Bell, K. R., Lin, D. N. C., Hartmann, L. W., & Kenyon, S. J. 1995, ApJ, 444, 376.CrossRefGoogle Scholar
Bell, K. R., Cassen, P. M., Klahr, H. H. & Henning, Th. 1997 to appear September, ApJ, 486.Google Scholar
Cassen, P., & Moosman, A. 1981, Icarus, 48, 353.Google Scholar
Chandler, C. J. & Richer, J. S. 1997, in Low Mass Star Formation from Infall to Outflow: Poster Proceedings, Eds. Malbet, F. & Castets, A., p. 76.Google Scholar
Chick, K. M. 1997, submitted to Journal of Quantitative Spectroscopy and Radiative Transfer.Google Scholar
Chick, K. M., & Cassen, P. 1997a, in Low Mass Star Formation from Infall to Outflow: Poster Proceedings, Eds. Malbet, F. & Castets, A., p. 207.Google Scholar
Chick, K. M. & Cassen, P. M. 1997b, ApJ, 477, 398.CrossRefGoogle Scholar
Chick, K. M., Pollack, J. B., & Cassen, P. M. 1996, ApJ, 461, 956.Google Scholar
Clarke, C. J., Lin, D. N. C., & Pringle, J. E. 1990, MNRAS, 242, 439.Google Scholar
Goodrich, R. W. 1987, PASP, 99, 116.CrossRefGoogle Scholar
Hartmann, L., Calvet, N., & Boss, A. 1996, ApJ, 464, 387.Google Scholar
Hartmann, L. & Kenyon, S. J. 1996, ARAA, 34, 207.CrossRefGoogle Scholar
Herbig, G. H. 1977, ApJ, 217, 693.Google Scholar
Kawazoe, E. & Mineshige, S. 1994, PASJ, 45, 715.Google Scholar
Kenyon, S. J., Calvet, N., & Hartmann, L. W. 1993, ApJ, 414, 676.Google Scholar
Kenyon, S. J. & Hartmann, L. W. 1991, ApJ, 383, 664.CrossRefGoogle Scholar
Kenyon, S. J., Hartmann, L., & Hewett, R. 1988, ApJ, 325, 231.Google Scholar
Lin, D. N. C. & Papaloizou, J. 1993, in Protostars and Planets III, eds. Levy, E. H. & Lunine, J. (Tucson: Univ. of Arizona Press), 749.Google Scholar
Lynden-Bell, D. & Pringle, J. E. 1974, MNRAS, 168, 603.CrossRefGoogle Scholar
Reipurth, B. 1989, Nature, 340, 42.Google Scholar
Shakura, N. I. & Sunyaev, R. A. 1973, A&A, 24, 337.Google Scholar
Turner, N. J. J., Bodenheimer, P., & Bell, K. R. 1997, ApJ, to appear May.Google Scholar