Abstract
A curved filament in a decaying active region (AR 8329) was observed on 9 September 1998 with a combination of several instruments. The main data base is a 4-hour long time series of 1 min cadence using the Lockheed tunable filter mounted in the Swedish Vacuum Solar Tower in La Palma (SVST). Filtergrams obtained at several wavelength positions in Hα images are used to derive Doppler images. Interleaved images in the magnetic sensitive Fe i 6302.5 Å line yield corresponding magnetograms. Supplementing observations are collected from TRACE and the French Multi-Channel Double Pass spectrograph (MSDP) mounted in the German VTT in Tenerife. The filament, which consists of several discrete fragments with nearly horizontal fine structures, undergoes activity and counter-streaming bulk flow, but without erupting. The magnetic field inversion line of this active region is complex and strongly influenced by intrusion of a positive polarity area in a following negative polarity of the region. The positive polarity area contains a small sunspot surrounded by moving magnetic features (MMFs). The MMFs interact directly with the parasitic polarities in the filament channel, and thereby gives rise to merging and canceling magnetic flux. When the interaction occurs at the location of the feet (`barbs') of the filament notable activations are observed (ejection of `blobs'). The ejections of `blobs' are preceded by twist of filament threads and the `blobs' move along downward bending field lines towards the photosphere close to the sound speed.
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Antiochos, S. K., MacNeice, P. J., and Spicer, D. S.: 2000, Astrophys. J. 536, 494.
Aulanier, G. and Démoulin, P.: 1998, Astron. Astrophys. 329, 1125.
Aulanier, G., Démoulin, P., Mein, N., van Driel-Gesztelyi, L., Mein P., and DeForest, 1998, Astron. Astrophys. 335, 309.
Aulanier, G., Démoulin, P., Mein, N., van Driel-Gesztelyi, L., Mein P., and Schmieder, B.: 1999, Astron. Astrophys. 342, 867.
Berger, T. E., De Pontieu, B., Fletcher, L., Schrijver, C. J., Tarbell, T. D., and Title, A. M.: 1999, Solar Phys. 190, 409.
Deng, Y. Y., Schmieder, B., Engvold, O., DeLuca, E., and Golub L.: 2000, Solar Phys. 195, 347.
Engvold, O.: 1993, in V. Rusin, P. Heinzel, and J.-C. Vial (eds.), Solar Coronal Structures, Proceedings from the 144th IAU Colloquium in Tatranská Lomnica, Slovakia, 20–24 September 1993. p. 297.
Engvold, O., Jakobsson, H., Tandberg-Hanssen, E., Gurman J. B., and Moses, D.: 2001, Solar Phys. 202, 293.
Engvold, O.: 2001, in J. L. Ballester and B. Roberts (eds.), INTAS Workshop on MHD Waves in Astrophysical Plasmas, Universitat de les Illes Baleares, Palma de Mallorca, 9–11 May 2001. p. 123.
Handy, B. N. et al. (47 co-authors): 1999, Solar Phys. 187, 229.
Harvey, K. and Harvey, J.: 1973, Solar Phys. 28, 61.
Heinzel, P. and Anzer, U.: 1999, Solar Phys. 184, 103.
Lin, Y. and Engvold, O.: 2002, Solar Phys., submitted
Martens, P. C. H. and Zwaan, C.: 2001, Astrophys. J. 558, 872.
Martin, S. F., 1989, in V. Ruždjak and E. Tandberg-Hanssen (eds.), 'Dynamics of Quiescent Prominences', Proc. IAU Colloq. 117, 1.
Martin, S. F., Bilimoria R., and Tracadas P. W.: 1994, in R. J. Rutten and C. Schrijver (eds.), Solar Surface Magnetism, Kluwer Academic Publishers, Dordrecht, Holland, p. 303.
Martin, S. F.: 1998, in D. Rust and B. Schmieder (eds.), Proc. IAU Colloq. 167, 419.
Poland, A. R. and Mariska, J. T.: 1986, Solar Phys. 104, 303.
Scharmer, G. B., Brown, D. S., Petterson, L., and Rehn, J.: 1985, Appl. Optics 24, 2558.
Schmieder, B.: 1989, in E. R. Priest (ed.), Dynamics and Structure of Quiescent Solar Prominences, D. Reidel Publ. Co., Dordrecht, Holland, p. 15.
Schmieder, B., Malherbe, J. M., Mein, P., and Tandberg-Hanssen, E.: 1984, Astron. Astrophys. 136, 81.
Schmieder, B., Raadu, M., and Wiik, J. E.: 1991, Astron. Astrophys. 252, 353.
Schmieder, B., Démoulin, P., Aulanier, G., and Golub, L.: 1996, Astrophys. J. 467, 881.
Schmieder, B., Delannée, C., Deng, Y. Y., Vial, J. C., and Madjarska, M.: 2000, Astron. Astrophys. 358, 728.
Schmieder, B., Deng, Y. Y., Dumitrache, C., Mein, N., Malherbe, J. M., and Staiger, J.: 2002, Solar Phys., submitted.
Title, A., Topka, K., Tarbell, T. et al.: 1992, Astrophys. J. 393, 782.
Tandberg-Hanssen, E.: 1994, The Nature of Solar Prominences, Kluwer Academic Publishers, Dordrecht, Holland.
Thompson, W. T. and Schmieder, B.: 1991, Astron. Astrophys. 243, 501.
Wang, Y. M.: 2001, Astrophys. J. 560, 456.
Yi, Z. and Engvold, O.: 1991, Solar Phys. 134, 275.
Zirker, J. B., Engvold, O., and Martin, S. F.: 1998, Nature 396, 440.
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Deng, Y., Lin, Y., Schmieder, B. et al. Filament activation and magnetic reconnection. Sol Phys 209, 153–170 (2002). https://doi.org/10.1023/A:1020924406991
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DOI: https://doi.org/10.1023/A:1020924406991