The Library

Coronal loop slow mode oscillations driven by the kink instability

Tools

Haynes, M. (Martin), Arber, T. D. and Verwichte, E. (Erwin). (2008) Coronal loop slow mode oscillations driven by the kink instability. Astronomy & Astrophysics, Vol.479 (No.1). pp. 235-239. ISSN 0004-6361

PDF
WRAP_Haynes_45_coronal_loop_aa8534-07[1].pdf - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (878Kb)

Official URL: http://dx.doi.org/10.1051/0004-6361:20078534

Abstract

Aims. To establish the dominant wave modes generated by an internal, m = 1 kink instability in a short coronal flux tube. Methods. The 3D MHD numerical simulations are performed using Lare3d to model the kink instability and the subsequent wave generation. The initial conditions are a straight, zero net current flux tube containing a twist higher than the kink instability threshold. Results. It is shown that the kink instability initially sets up a 1st harmonic (1st overtone) that is converted through the rearrangement of the magnetic field into two out-of-phase fundamental slow modes. These slow modes are in the two entwined flux tubes created during the kink instability. Conclusions. The long-lived oscillations established after a kink instability provide a possible way to identify whether sudden, short coronal loop brightenings may have resulted from a confined kink instability. The mode oscillation structure changes from the 1st harmonic to fundamental due to field line relaxation. The subsequent decay in the fundamental mode is comparable to observations and is caused by shock dissipation. This result has important consequences for the damping of the slow mode oscillations observed by SUMER.

Item Type:	Journal Article
Subjects:	Q Science > QB Astronomy
Divisions:	Faculty of Science > Physics
Library of Congress Subject Headings (LCSH):	Sun -- Corona -- Magnetic fields, Sun -- Loop prominences, Solar oscillations, Solar flares
Journal or Publication Title:	Astronomy & Astrophysics
Publisher:	EDP Sciences
ISSN:	0004-6361
Date:	February 2008
Volume:	Vol.479
Number:	No.1
Page Range:	pp. 235-239
Identification Number:	10.1051/0004-6361:20078534
Status:	Peer Reviewed
Access rights to Published version:	Open Access
Funder:	Particle Physics and Astronomy Research Council (Great Britain) (PPARC)
References:	Amari, T., & Luciani, J. F. 1999, ApJ, 515, L81 Amari, T., Luciani, J. F., Aly, J. J., & Tagger, M. 1996, ApJ, 466, L39 Arber, T. D., Longbottom, A. W., & Van der Linden, R. A. M. 1999, ApJ, 517, 990 Arber, T. D., Longbottom, A. W., Gerrard, C. L., & Milne, A. M. 2001, J. Comput. Phys., 171, 151 Aulanier, G., Démoulin, P., & Grappin, R. 2005, A&A, 430, 1067 Baty, H. 1997, A&A, 318, 621 Baty, H. 2000, A&A, 360, 345 Baty, H., & Heyvaerts, J. 1996, A&A, 308, 935 Birn, J., Forbes, T. G., & Hesse, M. 2006, ApJ, 645, 732 De Moortel, I., & Hood, A. W. 2003, A&A, 408, 755 Fan, Y. 2005, ApJ, 630, 543 Gerrard, C. L., & Hood, A. W. 2003, Sol. Phys., 214, 151 Gerrard, C. L., Arber, T. D., Hood, A. W., & Van der Linden, R. A. M. 2001, A&A, 373, 1089 Gerrard, C. L., Arber, T. D., & Hood, A. W. 2002, A&A, 387, 687 Gerrard, C. L., Hood, A. W., & Brown, D. S. 2004, Sol. Phys., 222, 79 Haynes, M., & Arber, T. D. 2007, A&A, 467, 327 Hood, A. W., & Priest, E. R. 1981, Geophysical and Astrophysical Fluid Dynamics, 17, 297 Kliem, B., Dammasch, I. E., Curdt, W., & Wilhelm, K. 2002, ApJ, 568, L61 Lionello, R., Velli, M., Einaudi, G., & Miki´c, Z. 1998, ApJ, 494, 840 Nakariakov, V. M., Verwichte, E., Berghmans, D., & Robbrecht, E. 2000, A&A, 362, 1151 Nakariakov, V. M., Tsiklauri, D., Kelly, A., Arber, T. D., & Aschwanden, M. J. 2004, A&A, 414, L25 Ofman, L., & Wang, T. 2002, ApJ, 580, L85 Selwa, M., Murawski, K., & Solanki, S. K. 2005, A&A, 436, 701 Taroyan, Y., Erdélyi, R., Doyle, J. G., & Bradshaw, S. J. 2005, A&A, 438, 713 Tokman, M., & Bellan, P. M. 2002, ApJ, 567, 1202 Török, T., & Kliem, B. 2003, A&A, 406, 1043 Török, T., & Kliem, B. 2005, ApJ, 630, L97 Török, T., Kliem, B., & Titov, V. S. 2004, A&A, 413, L27 Tsiklauri, D., Nakariakov, V.M., Arber, T. D.,&Aschwanden, M. J. 2004, A&A, 422, 351 Velli, M., Lionello, R., & Einaudi, G. 1997, Sol. Phys., 172, 257 Wang, T., Solanki, S. K., Curdt, W., Innes, D. E., & Dammasch, I. E. 2002, ApJ, 574, L101 Wang, T. J., Solanki, S. K., Curdt, W., et al. 2003, A&A, 406, 1105
URI:	http://wrap.warwick.ac.uk/id/eprint/3450