Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-23T15:23:12.297Z Has data issue: false hasContentIssue false
  • English
  • Français

Long-term stellar variability

Published online by Cambridge University Press:  26 February 2010

Isabella Pagano
Isabella Pagano*
Affiliation:
INAF - Osservatorio Astrofisico di Catania, v. Santa Sofia 78, p.le M. Rodonò, 95123Catania email: [email protected]
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.

Stars with significant subsurface convection zones develop magnetic loop structures that, arising from the surface upward to the external atmospheres, cause flux variability detectable throughout the whole electromagnetic spectrum. In fact, diagnostics of magnetic activity are in radio wavelengths, where gyrosincrotron radiation arises from the quiescent and flaring corona; in the optical region, where important signatures are the Balmer lines, the Ca ii IRT and H&K lines; in the UV and X ray domains, the latter mainly due to coronal thermal plasma. The zoo of different magnetic features observed for the Sun – spots, faculae, flares, CMEs – are characterized by different temporal evolution and energetics, both in quantity and quality. As a consequence, the time scale of variability, the amount of involved energy and the quality of the involved photons are used as fingerprints in interpreting the observed stellar variability in the framework of the solar-stellar analogy. Here I review main results from long-term multiwavelength observations of cool star atmospheres, with emphasis to similarities and differences with the solar case.

Keywords

stars: activitystars: spotsstars: chromospheresstars: coronaestars: mass loss
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. 136 - 145
Copyright
Copyright © International Astronomical Union 2010

References

Acton, L. 1996, ASP Conf. Ser. 109, p.45Google Scholar
Ayres, T. R., Fleming, T. A., Simon, T., et al. 1995, APJS, 96, 223CrossRefGoogle Scholar
Ayres, T. R. 2009, ApJ, 696, 1931CrossRefGoogle Scholar
Ayres, T. R. 1997, J. Geophys. Res., 102, 1641CrossRefGoogle Scholar
Ayres, T. R., Brown, A., Harper, G.M., et al. 2003, ApJ, 583, 963CrossRefGoogle Scholar
Baliunas, S. L., Donahue, R. A., Soon, W. H., et al. 1995, ApJ, 438, 269CrossRefGoogle Scholar
Baliunas, S. L., Donahue, R. A., Soon, W., & Henry, G. W. 1998, ASP Conf. Ser., 154, p. 153Google Scholar
Benz, A. & Güdel, M. 1994, A&A, 285, 621Google Scholar
Berdyugina, S. V. & Henry, G. W. 2007, ApJ, 659, L157CrossRefGoogle Scholar
Busà, I., Pagano, I., Rodonò, M., Neff, J. E., & Lanzafame, A. C. 1999, A&A, 350, 571Google Scholar
Catala, C., Donati, J.-F., Shkolnik, E., Bohlender, D., & Alecian, E. 2007, MNRAS, 374, L42CrossRefGoogle Scholar
Cayrel de Strobel, G. & Bentolila, C. 1989, A&A, 211, 324Google Scholar
Collier Cameron, A., Bedford, D. K., Rucinski, S. M., Vilhu, O., & White, N. E. 1988, MNRAS, 231, 131CrossRefGoogle Scholar
Donati, J.-F., Collier Cameron, A., & Petit, P. 2003a, MNRAS, 345, 1187CrossRefGoogle Scholar
Donati, J.-F., Collier Cameron, A., Semel, M. et al. 2003b, MNRAS, 345, 1145CrossRefGoogle Scholar
Donati, J.-F., Jardine, M. M., & Gregory, S. G. 2007, MNRAS, 380, 1297CrossRefGoogle Scholar
Favata, F. & Micela, G. 2003, Space Science Reviews, 108, 577CrossRefGoogle Scholar
Favata, F., Micela, G., Orlando, S. et al. 2008, A&A, 490, 1121Google Scholar
Gershberg, R. E. 2005, Solar-type Activity in Main-Sequence Stars, SpringerGoogle Scholar
Giardino, G., Pillitteri, I., Favata, F., & Micela, G. 2008, A&A, 490, 113Google Scholar
Güdel, M. & Benz, A. 1993, ApJ 405, L63CrossRefGoogle Scholar
Guedel, M., Schmitt, J. H. M. M., Benz, A. O., & Elias, N. M. 1995, A&A, 301, 201Google Scholar
Güdel, M. 2008, Living Reviews in Solar Physics, vol. 4, no. 3CrossRefGoogle Scholar
Hall, J. C., Henry, G. W., Lockwood, G. W., Skiff, B. A., & Saar, S. H. 2009, AJ 138, 312CrossRefGoogle Scholar
Hempelmann, A., Robrade, J., Schmitt, J. H. M. M., et al. 2006, A&A, 460, 261Google Scholar
Hussain, G. A. J., Brickhouse, N. S., & Dupree, A. K. 2005, ApJ, 621, 999CrossRefGoogle Scholar
Jordan, C., Ayres, T. R., Brown, A., Linsky, J. L., & Simon, T. 1987, MNRAS, 225, 903CrossRefGoogle Scholar
Jordan, C., Sim, S. A., McMurry, A. D., & Aruvel, M. 2001, MNRAS, 326, 303CrossRefGoogle Scholar
Kürster, M. & Dennerl, K. 1993, in Physics of Solar and Stellar Coronae, Linsky, J. F. & Serio, S. (eds.), Kluwer Acad. pub., p. 443Google Scholar
Lanza, A. F., Catalano, S., Cutispoto, G., Pagano, I., & Rodonò, M. 1998, A&A, 332, 541Google Scholar
Lanza, A. F., Pagano, I., Leto, G., et al. 2009a, A&A, 493, 193Google Scholar
Lanza, A. F., Aigrain, S., Messina, S., et al. 2009b, A&A, in press (arXiv:0901.4618)Google Scholar
Lockwood, G. W., Skiff, B. A., Henry, G. W., et al. 2007, ApJS, 171, 260CrossRefGoogle Scholar
Marino, A., Micela, G., Peres, G., & Sciortino, S. 2003, A&A, 407, L63Google Scholar
Messina, S. & Guinan, E. 2002, A&A, 393, 225Google Scholar
Messina, S. & Guinan, E. 2003,A&A, 409, 1017Google Scholar
Messina, S. 2008, A&A, 480, 495Google Scholar
Neff, J. E., Walter, F. M., Rodonò, M., & Linsky, J. L. 1989, A&A, 215, 79Google Scholar
Pagano, I., Linsky, J. L., & Carkner, L. 2000, ApJ, 532, 497CrossRefGoogle Scholar
Pagano, I., Rodonò, M., Linsky, J. L., et al. 2001, A&A, 365, 128Google Scholar
Pagano, I., Linsky, J. L., Valenti, J., & Duncan, D. K. 2004, A&A, 415, 331Google Scholar
Pagano, I., De Martino, C., Lanza, A. F., Spadaro, D., & Linsky, J. L. 2006, ESA-SP 617, 91Google Scholar
Parker, E. N. 1955 ApJ, 122, 293CrossRefGoogle Scholar
Patten, B. M. & Simon, T. 1996, ApJSS, 106, 489CrossRefGoogle Scholar
Peter, H. 2006, AdSpR, 39, 1814Google Scholar
Peter, H. & Judge, P. G. 1999, ApJ, 522, 1148CrossRefGoogle Scholar
Pizzolato, N., Maggio, A., Micela, G., Sciortino, S., & Ventura, P. 2003, A&A, 397, 147Google Scholar
Radick, R. R., Lockwood, G. W., Skiff, B. A., & Baliunas, S. L. 1998, APJSS, 118, 239CrossRefGoogle Scholar
Randich, S. 1998, ASP Conf. Ser., 154, p. 501Google Scholar
Redfield, S., Linsky, J. L., Ake, T. B., et al. 2002, ApJ, 581, 626CrossRefGoogle Scholar
Redfield, S., Ayres, T. R., Linsky, J. L., et al. 2002, ApJ, 585, 993CrossRefGoogle Scholar
Ribas, I., Guinan, E. F., Güdel, M., & Audard, M. 2005, ApJ, 622, 680CrossRefGoogle Scholar
Robrade, J., Schmitt, J. H. M. M., & Favata, F. 2005, A&A, 442, 315Google Scholar
Robrade, J., Schmitt, J. H. M. M., & Hempelmann, A. 2007, MSAIt, 78, 311Google Scholar
Rodonò, M. 1992 LNP, 397, 201Google Scholar
Rodonò, M. & Cutispoto, G. 1994, ASP Conf. Series, 64, 459Google Scholar
Rodonò, M., Messina, S., Lanza, A. F., Cutispoto, G., & Teriaca, L. 2000, A&A, 358, 624Google Scholar
Saar, S. 2006, BAAS 38, 240Google Scholar
Schrijver, C. J. 1987, ApJ 172, 111Google Scholar
Simon, T., Ayres, T. R., Redfield, S., & Linsky, J. L. 2002, ApJ, 579, 800CrossRefGoogle Scholar
Spadaro, D., Lanza, A. F., Lanzafame, A. C. et al. 2006, ApJ, 582, 486CrossRefGoogle Scholar
Stassun, K. G., van den Berg, M., Feigelson, E., & Flaccomio, E. 2006, ApJ, 649, 914CrossRefGoogle Scholar
Stelzer, B., Flaccomio, E., Briggs, K. et al. 2007, A&A, 468, 463Google Scholar
Strassmeier, K. G. 2009, IAU Symp, 259, 363Google Scholar
Telleschi, A., Güdel, M., Briggs, K., et al. 2005, ApJ, 622, 653CrossRefGoogle Scholar
Trigilio, C., Leto, P., & Umana, G. 1998, A&A, 330, 1060Google Scholar
Umana, G., Trigilio, C., Tumino, M., Catalano, S., Rodonò, M. 1995, A&A, 298, 143Google Scholar
Vida, K., Kovári, Zs., Ŝvanda, M. et al. 2007, AN, 328, 1078Google Scholar
Vilhu, O., Muhli, P., Huovelin, J., et al. 1998, AJ, 115, 1610CrossRefGoogle Scholar
Walker, G. A. H., Croll, B., Kuschnig, R., et al. 2007, ApJ 659, 1611CrossRefGoogle Scholar
Walker, G. A. H., Croll, B., Matthews, J. M., et al. 2008, A&A 482, 691Google Scholar
Walter, F. M., Neff, J. E., Gibson, D. M., et al. 1987, A&A, 186, 241Google Scholar
Wood, B. E., Linsky, J. L., & Ayres, T. R. 1997, ApJ, 478, 745CrossRefGoogle Scholar
Wood, B. E., Müller, H.-R., Zank, G. P., & Linsky, J. L. 2002, ApJ, 574, 412.CrossRefGoogle Scholar
Wood, B. E. 2004, Living Reviews in Solar Physics, Vol. 1, no. 2CrossRefGoogle Scholar
Wood, B. E., Müller, H.-R., Zank, G. P., Linsky, J. L., & Redfield, S. 2005, ApJ, 628, L143CrossRefGoogle Scholar