Bulletin of Taras Shevchenko National University of Kyiv. Astronomy, no. 51, p. 31-33 (2014)

Which is maximum of local magnetic field strength in active prominences?

V. Lozitsky, Dr. Phys. and Math. Sciences,
O. Botygina, eng,
V. Masliukh, Ph.D.
Taras Shevchenko National University of Kyiv

Abstract
The bisectors of I ± V Stokes profiles are analyzed for measurements of local magnetic field strengths in three active prominences of 4 July 1981, 24 July 1999 and 12 July 2004 observed on Echelle spectrograph of horizontal solar telescope of the Astronomical Observatory of Kyiv Taras Shevchenko National University. Three main types of bisectors were observed which indicate the essential magnetic field inhomogeneity. The calculations in frame of two-component model shown that true local magnetic field strengths in spatially unresolved structures сan be 4-5 times more than parameter В0.9 which was proposed earlier for a simple low empirical estimation of local magnetic field in prominences. The strongest magnetic fields were found in prominence of 24 July 2004 where parameter В0.9 reachs 6 kG, and local field according to modelling – nearly 25-30 kG. In places of presence of such extremely strong fields, the Нα line profiles are 5 times narrower than obtained from direct observations.

Keywords
Solar prominences, local magnetic fields

References
Botigіna, O.O., Lozic’kij, V.G. 2012, Vіsnik Astronomіchnoї shkoli, 8, 1–2, 159
Kurochka, E.V., Kurochka, L.N., Lozickij, V.G. 1980, Vestnik Kiev. un-ta. Astronomiya, 22, 48
SHpital’naya, A.A., Vyal’shin, G.F. 1970, Solnechnye dannye, 4, 100
Casini, R., Lopez Ariste, A., Tomczyk, S., Lites, W.B. 2003, Ap. J. Let.,598, 67
Kuckein, C., Centeno, R., Martinez Pillet, V., Casini, R., MansoSainz, R., Shimizu, T. 2009, Astronomy and Astrophysics. 501, 3, 1113
Lozitsky, V.G. 2011, International Journal of Astronomy and Astrophys,1,3,147
Lozitsky, V.G., Botygina, O.A. Astronomy Letters, 2012, 38, 6, 380
Trujillo Bueno, J., Merenda, L., Centeno, R., Collados, M. 2005, Ap. J. Let. 619, 191

Full text PDF