Astronomical School’s Report, 2004, Volume 5, Issue 1-2, Pages 198–206

https://doi.org/10.18372/2411-6602.05.1198
Download PDF
UDC 523.985 + 52–337

Spectral manifestations of the small-scale magnetic field inhomogeneity in solar flare on 25 October 2003

Osika O.B., Lozits’ky V.G.

Astronomical Observatory, Kyiv Shevchenko National University, Ukraine

Abstract

We present the results of investigation of the M1.8/2N solar flare on 25 October 2003 which has been arised in active region NOAA 10484. Two spectral lines of FeI, 630.15 and 630.25 nm, were investigated to diagnose the small-scale magnetic field structures. It was found that measured averaged longitudinal magnetic field Вk in FeI 630.25 line exceeds similar field in FeI 630.15 for flare region whereas for non-flare places these fields were practically the same. So long as these line shave practically the same hights of formation and temperature sensitivities but different Lande factors, this effect is a evidence to the spatially unresolved magnetic field structure with true magnetic strengths more than 100 mT. Detailed study of the Stokes I ±V profiles bisectors shown that their shape do not corresponds the case of a homogeneous field. The minimum of bisector splitting В was found for reduced distances from line center λn =17–21 pm, that indicates the existence the small-scale magnetic field of opposite polarity with strength of B =490±50mT. Likely, occuring of such much strong fields in this active region causes the violent energy process in form of solar flare.

Keywords:

References

  1. Gurtovenko E.A., Kostyk R.I. Fraungoferov spektr i sistema solnechnykh sil ostsillyatorov, Kiev: Naukova dumka, 1989, 200 p.
  2. Zemanek E.N., Stefanov A.P. Rasscheplenie nekotorykh spektral’nykh liny FeI v magnitnom pole, Vestnik Kievskogo un-ta. Seriya Astronomiya, 1976, Vyp. 18, P. 20–36.
  3. Kurochka E.V., Kurochka L.N., Lozitsky V.G., Lozitskaya N.I., Ostapenko V.A., Polupan P.N., Romanchuk P.R., Rossada V.M. Gorizontal’nyy solnechnyy teleskop Astronomicheskoy observatorii Kievskogo universiteta, Vestnik Kiev. un-ta. Seriya Astronomiya, 1980, Vyp. 22, P. 48–56.
  4. Lozitsky V.G., Lozitskaya N.I., Vlasenko V.I. Sravnenie rezul’tatov izmereny solnechnykh magnitnykh poley, poluchennykh raznymi metodami, Vestnik Kievskogo universiteta. Seriya Astronomiya, 1985, Vyp. 27, P. 59–66.
  5. Lozitsky V.G. Melkomasshtabnaya struktura solnechnykh magnitnykh poley, Kinematika i fizika nebes. tel, 1986, 2, No 1, P. 28–35.
  6. Lozyts’kyy V.H. Syl’ni mahnitni polia v malomasshtabnykh strukturakh ta spalakhakh na Sontsi: Avtoreferat dys. ... d-ra f.-m. nauk: 01.03.03, Kyyiv, 2003, 28 p.
  7. Lozitsky V.G., Lozitsky V.V. Diagnostika melkomasshtabnykh magnitnykh poley v solnechnoy vspyshke 29 marta 2001 g., Izvestiya KrAO, 2002, 98, P. 202.
  8. Prist E. Solnechnaya magnitogidrodinamika, M.: Mir, 1985, 592 c.
  9. Severnyy A.B. Nekotorye problemy fiziki Solntsa, M.: Nauka, 1988, 224 p.
  10. Cerdena D., Almeida J.S., Kneer F. Inter-network magnetic fields observed with sub-arcsec resolution, Astron. Astrophys, 2003, 407, P. 741–757. https://doi.org/10.1051/0004-6361:20030892
  11. Parker E.N. Solar activity and classical physics, Chinese Journal of Astronomy and Astrophysics, 2001, 1, No 2, P. 99–124. https://doi.org/10.1088/1009-9271/1/2/99
  12. Stenflo J.O. Magnetic-field structure of the photospheric network, Solar Physics, 1973, 32, No 1, P. 41–63. https://doi.org/10.1007/bf00152728
  13. Unno W. Line formation of a normal Zeeman triplet, Publs. Astron. Soc. Japan, 1956, 8, P. 108–125.
  14. Webb D.F., Allen J.H. Spacecraft and ground anomalies related to the October–November 2003 solar activity, Space Weather, 2004, 1, No 3, P. 6–8. https://doi.org/10.1029/2004sw000075

Download PDF