Abstract
The spatial-distribution dynamics of the hot coronal plasma with T ∼ 10 MK during a period of high solar activity is studied. We analyze images of the NOAA 9830 active region and its surroundings obtained during the second half of February 2002 with the SPIRIT spectroheliograph in the Mg XII 8.42-Å line and simultaneously on the SOHO satellite with the EIT instrument and on the TRACE satellite in the 195-Å channel. As shown by a multiwavelength analysis, a high-temperature plasma is concentrated in the corona near the apices of magnetic loops, it has long lifetimes (up to several days), and its dynamics is complex and bears no direct relation to flare activity. During the flares, conspicuous increases are observed in the X-ray flux and the emission measure for temperatures of ∼5–15 MK. Our analyses of the time variations in emission during a flare suggest that hot plasma is heated by fluxes of accelerated electrons.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
REFERENCES
Aschwanden, M.J., Fletcher, L., Schrijver, C., and Alexander, D., Coronal Loop Oscillations Observed with the Transition Region and Coronal Explorer, Astrophys. J., 1999, vol. 520, p. 880.
Edwin, P.M. and Roberts, B., Wave Propagation in a Magnetically Structured Atmosphere. III. The Slab in a Magnetic Environment, Solar Phys., 1982, vol. 76, p. 239.
Masuda, S., Kosugi, T., Hara, H., et al., A Loop-Top Hard X-ray Source in a Compact Solar Flare as Evidence for Magnetic Reconnection, Nature, 1994, vol. 371, p. 495.
Neupert, W.M., Comparison of Solar X-ray Line Emission with Microwave Emission during Flares, Astrophys. J. 1968, vol. 153, p. L59.
Oraevsky, V.N. and Sobelman, I.I., Comprehensive Studies of Solar Activity on the CORONAS-F Satellite, Pis'ma Astron. Zh., 2002, vol. 28, no.6, p. 457 [Astron. Lett. (Engl. Transl.), 2002, vol. 28, no. 6, p. 401].
Robert, B., Edwin, P.M., and Benz, A.O., On Coronal Oscillations, Astrophys. J., 1984, vol. 279, p. 857.
Tsuneta, S., Masuda, S., and Kosugi, T., Hot and Superhot Plasmas above an Impulsive Flare Loop, Astrophys. J., 1997, vol. 478, p. 787.
Wang, T.J., Solanki, S.K., Curdt, W., et al., Doppler Shift Oscillations of Hot Solar Coronal Plasma Seen by SUMER: A Signature of Loop Oscillations? Astrophys. J., 2002a, vol. 574, p. L101.
Wang, T.J., Solanki, S.K., Curdt, W., et al., Hot Loop Oscillations Seen by SUMER: Examples and Statistics, Proc. Euro Conf. and IAU Coll. 188, Santorini, Greece, 2002b ESA SP-505.
Zhitnik, I.A., Bugaenko, O.I., Ignatiev, A.P., et al., Dynamic 10 MK Plasma Structures Observed in Monochromatic Full-Sun Images by the SPIRIT Spectroheliograph on the CORONAS-F Mission, Mon. Not. R. Astron. Soc., 2003, vol. 338, p. 67.
Author information
Authors and Affiliations
Additional information
__________
Translated from Astronomicheskii Vestnik, Vol. 39, No. 6, 2005, pp. 571–576.
Original Russian Text Copyright © 2005 by Bogachev, Kuzin, Zhitnik, Urnov, Grechnev.
Rights and permissions
About this article
Cite this article
Bogachev, S.A., Kuzin, S.V., Zhitnik, I.A. et al. The Dynamics of High-Temperature Plasma in the Solar Corona according to SPIRIT Observations in Mg XII 8.42 Å Line. Sol Syst Res 39, 508–512 (2005). https://doi.org/10.1007/s11208-005-0064-8
Received:
Issue Date:
DOI: https://doi.org/10.1007/s11208-005-0064-8