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What can X-rays tell us about accretion, mass loss and magnetic fields in young stars?

Published online by Cambridge University Press:  01 May 2007

Thierry Montmerle*
Affiliation:
Laboratoire d'Astrophysique de Grenoble, BP 53X, 38400 St Martin d'Hères, France email: montmerle@obs.ujf-grenoble.fr
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Abstract

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Until recently, X-rays from low-mass young stars (105–106 yr) were thought to be a universal proxy for magnetic activity, enhanced by 3-4 orders of magnitude with respect to the Sun, but otherwise similar in nature to all low-mass, late-type convective stars (including the Sun itself). However, there is now evidence that other X-ray emission mechanisms are at work in young stars. The most frequently invoked mechanism is accretion shocks along magnetic field lines (“magnetic accretion”). In the case of the more massive A- and B-type stars, and their progenitors the Herbig AeBe stars, other, possibly more exotic mechanisms can operate: star-disk magnetic reconnection, magnetically channeled shocked winds, etc. In any case, magnetic fields, both on small scale (surface activity) and on large scale (dipolar magnetospheres), play a distinctive role in the emission of X-rays by young stars, probably throughout the IMF.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2007

References

André, P., et al. 1988, ApJ 335, 940CrossRefGoogle Scholar
Babel, J., & Montmerle, T. 1997, ApJ (Letters) 485, L29CrossRefGoogle Scholar
Berghöfer, T.W., et al. 1997, A&A 322, 167Google Scholar
Bouvier, J., et al. 2007, A&A 463, 1017Google Scholar
Brun, A. S., Zahn, J.-P. 2006, A&A 457, 665Google Scholar
Deleuil, M., et al. 2005, A&A 429, 247Google Scholar
Donati, J.-F., et al. 2002, MNRAS 333, 55CrossRefGoogle Scholar
Donati, J.-F., et al. 2007, in 14th Cambridge Workshop on Cool Stars Sellar Systems, and the Sun, Ed. van Belle, G., ASP Conf. Ser., in press (astro-ph/0702159)Google Scholar
Favata, F., et al. 2005, ApJ(Suppl.) 160, 469Google Scholar
Feigelson, E. D., & Montmerle, T. 1999, ARA&A 37, 363Google Scholar
Gagné, M., et al. 1997, ApJ (Letters) 478, L87CrossRefGoogle Scholar
Getman, K. V., et al. 2005, ApJS 160, 319CrossRefGoogle Scholar
Grosso, N., et al. 2007, A&A in pressGoogle Scholar
Güdel, M. 2004, Astr.Ap.Rev. 12, 71Google Scholar
Güdel, M., et al. 2006, A&A in press (astro-ph/0609160)Google Scholar
Günther, H. M., et al. 2006, A&A 459, L29Google Scholar
Hillenbrand, L. A. 2006, in A Decade of Discovery: Planets Around Other Stars, Ed. Livio, M., STScI Symposium Ser., 19, in pressGoogle Scholar
Hubrig, S., et al. 2007, A&A 463, 1039Google Scholar
Kastner, J. H., et al. 2002, ApJ 567, 434CrossRefGoogle Scholar
Kudritzki, R.-P., & Puls, J. 2000, ARA&A 38, 613Google Scholar
MacDonald, J., Mullan, D. J. 2004, MNRAS 348, 702CrossRefGoogle Scholar
Micela, G., Favata, F. 2005, Sp. Sci. Rev. 108, 577Google Scholar
Michaud, G. 2004, in The A-Star Puzzle, Eds. Zverko, J. et al. , IAUS 224 (Cambridge, UK: Cambridge University Press), p.173Google Scholar
Montmerle, T. 2001, Science 293, 2409CrossRefGoogle Scholar
Montmerle, T. 2007, Mem. Soc. Astr. It. in pressGoogle Scholar
Montmerle, T., et al. 2000, ApJ 532, 1097CrossRefGoogle Scholar
Owocki, S.P., & Cohen, D.H. 1999, ApJ 520, 833CrossRefGoogle Scholar
Ozawa, H., Grosso, N., Montmerle, T. 2005, A&A 438, 963Google Scholar
Peres, G., Orlando, S., Reale, F. 2004, ApJ 612, 472CrossRefGoogle Scholar
Preibisch, T. 2004, A&A 428, 569Google Scholar
Preibisch, T., et al. 2005, ApJS 160, 401CrossRefGoogle Scholar
Pudritz, R. E., et al. 2007, in Protostars and Planets V, Eds. Reipurth, B., Jewitt, D., & Keil, K. (Tucson: University of Arizona Press), p.277Google Scholar
Robrade, J., Schmitt, J. H. M. M. 2006, A&A 449, 737Google Scholar
Romanova, M. M., et al. 2004, ApJ 610, 920CrossRefGoogle Scholar
Schulz, N. S., et al. 2003, ApJ 595, 365CrossRefGoogle Scholar
Stassun, K. G. 2001, in From Darkness to Light, Eds. Montmerle, T. & André, P., ASP Conf. Ser., 243, p.599Google Scholar
Stelzer, B., Flaccomio, E., Montmerle, T., et al. 2005, ApJS 160, 557CrossRefGoogle Scholar
Stelzer, B., et al. 2006, A&A 457, 223Google Scholar
Strassmeier, K. G., Rice, J. B. 2006, A&A 460, 751Google Scholar
Swartz, D. A., et al. 2005, ApJ 628, 811CrossRefGoogle Scholar
Telleschi, A., et al. 2007, A&A in press (astro-ph/0610456)Google Scholar
Townsend, R. H. D., Owocki, S. P. 2005, MNRAS 357, 251CrossRefGoogle Scholar
Trigilio, C., et al. 2004, A&A 418, 593Google Scholar
Wade, G.A. 2005, in Element Statification in Stars, Eds. Alecian, G., Richard, O., & Vauclair, S., EAS Publ. Series, 17, p.227Google Scholar
Wade, G. A., et al. 2006, A&A 451, 195Google Scholar
Wolk, S. J., et al. 2005, ApJ 160, 423Google Scholar
Yang, Hao, Johns-Krull, C. M., Valenti, J. A. 2007, ApJ 133, 73CrossRefGoogle Scholar
Zinnecker, H., Preibisch, T. 1994, A&A 292, 152Google Scholar