Hostname: page-component-78c5997874-t5tsf Total loading time: 0 Render date: 2024-11-13T11:52:16.980Z Has data issue: false hasContentIssue false
  • English
  • Français

Detailed characterization of stellar high energy (FUV/EUV/X-ray) radiation fields during protoplanetary system formation

Published online by Cambridge University Press:  26 February 2010

Alexander Brown
Alexander Brown*
Affiliation:
Center for Astrophysics and Space Astronomy, University of Colorado, Boulder, CO 80309-0389, USA email: Alexander.Brown@colorado.edu
Rights & Permissions [Opens in a new window]

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.

Young stars undergoing the conversion of pre-main-sequence circumstellar disks into protoplanetary systems are strong sources of high energy (FUV/EUV/X-ray) radiation that controls the physical and chemical processes in their circumstellar environment out to hundreds of AU from the star. The high energy radiation resulting from magnetic activity and accretion onto the central star controls the thermal structure of disks, the formation process of planetesimals, and the photoexcitation and photoionization of protoplanets and young planetary atmospheres. Modeling of the dust and gas evolution requires an accurate understanding of the local radiation field throughout the ultraviolet (UV) and X-ray spectral regions, even those parts of the spectrum that are impossible to observe from Earth.

Our current research efforts are directed towards developing a better understanding of UV (using HST and FUSE) and X-ray (using Chandra, XMM-Newton, and Swift) stellar activity and the resulting radiation fields during pre-main-sequence evolution from ages of a few to several hundred million years. These studies include extensive UV and X-ray spectral sampling of individual stars in nearby star formation regions and the various moving groups of the Local Association, including our HST Cycle 17 Large Project (GO-11616), which is using 111 HST orbits to observe 32 T Tauri stars with the COS UV spectrograph. Most young stars are well over 100 pc from the Sun and are consequently hard to observe in the UV and X-ray regions at even moderate spectral resolution. However, members of the Local Association, whose ages range from 7 Myr to a few hundred Myr, surround the Sun at distances of 50 pc or less and permit the detailed study of the later stages of the early evolution of stellar activity when gas giant and terrestrial protoplanets are forming. We illustrate our methodology using the 12 Myr old early-M dwarf AU Mic, which possesses a striking dust debris disk, as an example.

Keywords

stars: pre–main-sequencestars: activityplanetary systems: formationplanetary systems: protoplanetary disks
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 5 , Symposium S264: Solar and Stellar Variability: Impact on Earth and Planets , August 2009 , pp. 395 - 400
Copyright
Copyright © International Astronomical Union 2010

References

Alexander, R. D., Clarke, C. J., & Pringle, J. E. 2006, MNRAS, 369, 229CrossRefGoogle Scholar
Bergin, E. A. 2009, in: Garcia, P. (ed.), Physical Processes in Circumstellar Disks Around Young Stars, (Chicago: University of Chicago Press), in pressGoogle Scholar
Blum, J. & Wurm, G. 2008, ARAA, 46, 21Google Scholar
Cully, S. L., Siegmund, O. H. W., Vedder, P. W., & Vallerga, J. V. 1993, ApJ(Letters), 414, L49CrossRefGoogle Scholar
Dullemond, C. P., Hollenbach, D., Kamp, I., & D'Alessio, P. 2007, in: Reipurth, B., Jewitt, D., and Keil, K. (eds.), Protostars and Planets V (Tucson: University of Arizona Press), p. 555Google Scholar
Eggen, O. J.AJ, 104, 2141Google Scholar
Feigelson, E. & Montmerle, T. 1999, ARAA, 37, 363Google Scholar
Froning, C. S. & Green, J. C. 2009, Ap&SS, 320, 181Google Scholar
Glassgold, A. E., Najita, J., & Igea, J., 2004, ApJ, 615, 972Google Scholar
Gorti, U. & Hollenbach, D. 2009, ApJ, 690, 1539CrossRefGoogle Scholar
Güdel, M., Briggs, K. R., Arzner, K., Audard, M., Bouvier, J., Feigelson, E. D., Franciosini, E., Glauser, A., Grosso, N., Micela, G., Monin, J.-L., Montmerle, T., Padgett, D. L., Palla, F., Pillitteri, I., Rebull, L., Scelsi, L., Silva, B., Skinner, S. L., Stelzer, B., & Telleschi, A. 2007, A&A, 468, 379Google Scholar
Montes, D, López-Santiago, J., Gálvez, M. C., Fernández-Figueroa, M. J., De Castro, E., & Cornide, M. 2001, MNRAS, 328, 45CrossRefGoogle Scholar
Osten, R., Drake, S., Godet, O., Pye, J., Barthelmy, S. D., Cummings, J., Pal'shin, V., Golenetskii, S., Tueller, J., & Krimm, H. 2008, ATel, 1499Google Scholar
Osten, R. A., Drake, S., Tueller, J., Cummings, J., Perri, M., Moretti, A., & Covino, S. 2007, ApJ, 654, 1052Google Scholar
Osten, R. A., Hawley, S. L., Allred, J. C., Johns-Krull, C. M., & Roark, C. 2005, ApJ, 621, 398Google Scholar
Owen, J. E., Ercolano, B., Clarke, C. J., & Alexander, R. D. 2009, MNRAS, in pressGoogle Scholar
Stelzer, B., Flaccomio, E., Briggs, K., Micela, G., Scelsi, L., Audard, M., Pillitteri, I., & Güdel, M. 2007, A&A, 468, 463Google Scholar
Torres, C. A. O., Quast, G. R., Melo, C. H. F., & Sterzik, M. F. 2008, in: Reipurth, B. (ed.) Handbook of Star Forming Regions Vol. II (San Francisco: Astronomical Society of the Pacific), p. 757Google Scholar
Wyatt, M. C. 2008, ARAA, 46, 339Google Scholar
Zuckerman, B. & Song, I. 2004, ARAA, 42, 685CrossRefGoogle Scholar