Abstract
We analyze the evolution of the flare/postflare-loop system in the two-ribbon flare of November 3, 2003, utilizing multi-wavelength observations that cover the temperature range from several tens of MK down to 104 K. A non-uniform growth of the loop system enables us to identify analogous patterns in the height–time, h(t), curves measured at different temperatures. The “knees,” “plateaus,” and “bends” in a higher-temperature curve appear after a certain time delay at lower heights in a lower-temperature curve. We interpret such a shifted replication as a track of a given set of loops (reconnected field lines) while shrinking and cooling after being released from the reconnection site. Measurements of the height/time shifts between h(t) curves of different temperatures provide a simultaneous estimate of the shrinkage speed and cooling rate in a given temperature domain, for a period of almost ten hours after the flare impulsive phase. From the analysis we find the following: (a) Loop shrinkage is faster at higher temperatures – in the first hour of the loop-system growth, the shrinkage velocity at 5 MK is 20 – 30 km s−1, whereas at 1 MK it amounts to 5 km s−1; (b) Shrinking becomes slower as the flare decays – ten hours after the impulsive phase, the shrinkage velocity at 5 MK becomes 5 km s−1; (c) The cooling rate decreases as the flare decays – in the 5 MK range it is 1 MK min−1 in the first hour of the loop-system growth, whereas ten hours later it decreases to 0.2 MK min−1; (d) During the initial phase of the loop-system growth, the cooling rate is larger at higher temperatures, whereas in the late phases the cooling rate apparently does not depend on the temperature; (e) A more detailed analysis of shrinking/cooling around one hour after the impulsive phase reveals a deceleration of the loop shrinkage, amounting to ā ≈ 10 m s−2 in the T < 5 MK range; (f) In the same interval, conductive cooling dominates down to T ≈ 3 MK, whereas radiation becomes dominant below T ≈ 2 MK; (g) A few hours after the impulsive phase, radiation becomes dominant across the whole T < 5 MK range. These findings are compared with results of previous studies and discussed in the framework of relevant models.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Antiochos, S.K. and Sturrock, P.A.: 1978, Astrophys. J. 220, 1137.
Aschwanden, M.J. and Alexander, D.: 2001, Solar Phys. 204, 93.
Cargill, P.J.: 1994, Astrophys. J. 422, 381.
Culhane, J.L., Vesecky, J.F., and Phillips, K.J.H.: 1970, Solar Phys. 15, 394.
Culhane, J.L., Phillips, A.T., Inda-Koide, M., et al.: 1994, Solar Phys. 153, 307.
Dauphin, C., Vilmer., N., Lüthi, T., Trottet, G., Krucker, S., and Magun, A.: 2005, Adv. Space Res. 35, 1805.
Delaboudinière, J.-P.: Artzner, G.E.; Brunaud, J., et al.: 1995, Solar Phys. 162, 291.
Dowdy, J.F., Jr., Moore, R.L., and Wu, S.T.: 1985, Solar Phys. 99, 79.
Forbes, T.G.: 1986, Astrophys. J. 305, 553.
Forbes, T.G. and Acton, L.W.: 1996, Astrophys. J. 459, 330.
Furth, H.P., Kileen, J., and Rosenbluth, M.N.: 1963, Phys. Fluids 6, 459.
Gekelman, W. and Pfister, H.: 1988, Phys. Fluids 26, 1949.
Heinzel, P. and Karlický, M.: 1987, Solar Phys. 110, 343.
Hiei, E.: 1994, in V. Sušin, P. Heinzel, and J.-C. Vial (eds.), IAU Colloq., Solar Coronal Structures 144, 163.
Hill, S.M., Pizzo, V.J., Balch, C.C., Biesecker, D.A., Bornmann, P. Hildner, E., et al.: 2005, Solar Phys. 226, 255.
Hurford, G.J., Schmahl, E.J., Schwartz, R.A, et al.: 2002, Solar Phys. 210, 61.
Innes, D.E., McKenzie, D.E., and Wang, T.: 2003, Solar Phys. 217, 267.
Karlický, M. and Kosugi, T.: 2004, Astron. Astrophys. 419, 1159.
Karlický, M., Veronig, A., and Vršnak, B.: 2005, Hvar Observ. Bull., in press.
Ko, Y., Raymond, J.C., Lin, J., Lawrence, G., Li, J., and Fludra, A.: 2003, Astrophys. J. 594, 1068.
Li, Y.P. and Gan, W.Q.: 2005, Astrophys. J. 629, L137.
Lin, J.: 2004, Solar Phys. 222, 115.
Lin, J. and Forbes, T.G.: 2000, J. Geophys. Res. 105, 2375.
Lin, J., Forbes, T.G., Priest, E.R., and Bungey, T.N.: 1995, Solar Phys. 159, 275.
Lin, J., Ko, Y.-K., Sui, L., et al.: 2005, Astrophys. J. 622, 1251.
Lin, R.P., Dennis, B.R., Hurford, G.J., et al.: 2002, Solar Phys. 210, 3.
Lin, R.P., Schwartz, R.A., Pelling, R.M., and Hurley, K.C.: 1981, Astrophys. J. 251, L109.
Liu, W., Jiang, Y.W., Liu, S., and Petrosian, V.: 2004, Astrophys. J. 611, L43.
McKenzie, D.E.: 2000, Solar Phys. 195, 381.
McKenzie, D.E. and Hudson, H.S.: 1999, Astrophys. J. 519, L93.
Newkirk, G., Jr.: 1961, Astrophys. J. 133, 983.
Otruba, W.: 1999, in B. Schmieder, A. Hofmann, and J. Staude (eds.), Third Advances in Solar Physics Euroconference: Magnetic Fields and Oscillations, ASP Conference Series, Vol. 184, p. 314.
Otruba, W. and Pötzi, W.: 2003, Hvar Observ. Bull. 27, 189.
Pizzo, V.J., Hill, S.M., Balch, C.C., Biesecker, D.A., Bornmann, P., Hildner, E., et al.: 2005, Solar Phys. 226, 283
Priest, E.R.: 1982, Solar Magnetohydrodynamics, D. Reidel, Dordrecht.
Saito, K: 1970, Ann. Tokyo Astr. Obs. 12, 53.
Schmieder, B., Heinzel, P., Van Driel-Gesztelyi, L., and Lemen, J.R.: 1996, Solar Phys. 165, 303.
Sheeley, N.R., Jr. and Wang, Y.-M.: 2002, Astrophys. J. 579, 874.
Sheeley, N.R., Jr., Warren, H.P., and Wang, Y.-M.: 2004, Astrophys. J. 616, 1224.
Švestka, Z.: 1976, Solar Flares, Reidel, Dordrecht.
Švestka, Z.: 1986, in D. Neidig (ed.), Proceedings of the NSO/SMM Symposium on the Lower Atmosphere of Solar Flares, p. 332.
Švestka, Z.: 1987, Solar Phys. 108, 411.
Švestka, Z., Fontenla, J.M., Machado, M.E., Martin, S.F., Neidig, D.F., and Poletto, G.: 1987, Solar Phys. 108, 237.
Ugai, M.: 1987, Geophys. Res. Lett. 14, 103.
Van Driel-Gesztelyi, L., Schmieder, B., Wiik, J.-E., et al.: 1996, in R.D. Bentley and J.T. Mariska (eds.), Magnetic Reconnection in the Solar Atmosphere, ASP Conference Series, Vol. 111, p. 359.
Varady, M. and Heinzel, P.: 1997a, Hvar Observ. Bull. 21, 33.
Varady, M. and Heinzel, P.: 1997b, in A. Wilson (ed.), Fifth SOHO Workshop: The Corona and Solar Wind Near Minimum Activity, ESA-SP404, pr 705.
Veronig, A., Karlický, M., Vršnak, B., Temmer, M., Magdalenić, J., Dennis, B.R., Otruba, W., and Pötzi, W.: 2005, Astron. Astrophys. 446, 675.
Vršnak, B. and Skender, M.: 2004, Solar Phys. 226, 97.
Vršnak, B., Klein, K.-L., Warmuth, A., Otruba, W., and Skender, M.: 2003, Solar Phys. 214, 325.
Vršnak, B., Magdalenić, J., and Zlobec, P.: 2003, Astron. Astrophys. 413, 753.
Vršnak, B., Magdalenić, J., Temmer, M., Veronig, A., Warmuth, A., Mann, G., Aurass, H., and Otruba, W.: 2005, Astrophys. J. 625, L67.
Vršnak, B., Warmuth, A., Temmer M., Veronig, A., Magdalenić, J., Hillaris, A., and Karlický, M.: 2006, Astron. Astrophys., in press.
Webb, D.F., Burkepile, J., Forbes, T.G., and Riley, P.: 2003, J. Geophys. Res. 108, 1440.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Vršnak, B., Temmer, M., Veronig, A. et al. Shrinking and Cooling of Flare Loops in a Two-Ribbon Flare. Sol Phys 234, 273–299 (2006). https://doi.org/10.1007/s11207-006-0093-6
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s11207-006-0093-6