Changes of geomagnetic transmissivity in the disturbed magnetosphere: ground-based and CORONAS-F observations
Abstract
We report increases of cosmic-ray intensity at lowL shells, on the ground as well as on the altitude of 500 km, during the selected intervals when magnetosphere was strongly disturbed. The geomagnetic transmissivity for cosmic ray vertical access has been computed for four events, using two geomagnetic field models. The first event, namely, dated November 20–22, 2003, led to an increase of galactic cosmic-ray intensity due to the improvement of magnetospheric transmissivity at neutron monitors with high nominal cut-off rigidity. Other two events with high-energy solar proton emissions, namely, dated October 28 and November 2, 2003, caused different responses at middle latitudes. The first one followed by the strong geomagnetic disturbance led to the shift of the penetration boundary of protons, having(50–90) MeV at CORONAS-F satellite toL<3, coinciding approximately with the cut-off reduction expected byDst depression, while the other one, without remarkableDst decrease, did not shift the outer boundary of penetration belowL ≈ 4. And the fourth of the events, on November 8, 2004, with strong geomagnetic disturbance, yielded a complicated structure of cosmic-ray time profiles: superimposed on the cosmic-ray decrease, viewed by neutron monitors and by CORONAS-F at high latitude; an increase of intensity at middle latitudes both on the ground and on the altitude of 500 km has been observed during theDst depression.
PACS
94.20.wqKey words
cosmic rays solar energetic particles cut-off rigidityPreview
Unable to display preview. Download preview PDF.
References
- [1]M.A. Shea, D.F. Smart, and K.G. McCracken: J. Geophys. Res.70 (1965) 4117.ADSCrossRefGoogle Scholar
- [2]H. Miyasaka, K. Kudela, S. Shimoda et al.: inProc. 28th ICRC, Tsukuba, 2003, Vol. 6, p. 3609.Google Scholar
- [3]M.I. Tyasto, O.A. Danilova, N.G. Ptitsyna et al.: Geomagn. Aeronomy44 (2004) 270.Google Scholar
- [4]D.F. Smart and M.A. Shea: Adv. Space Res.28 (2001) 1733.CrossRefADSGoogle Scholar
- [5]R.A. Leske, R.A. Mewaldt, E.C. Stone et al.: J. Geophys. Res.106 (A12) (2001) 30011.CrossRefADSGoogle Scholar
- [6]D.F. Smart, M.A. Shea, M.J. Golightly et al.: Adv. Space Res.31 (2003) 841.CrossRefADSGoogle Scholar
- [7]E.O. Flückiger, D.F. Smart, M.A. Shea et al.: J. Geophys. Res.91 (1986) 7925.ADSCrossRefGoogle Scholar
- [8]D.F. Smart and M.A. Shea: Adv. Space Res.28 (2001) 1733.CrossRefADSGoogle Scholar
- [9]B.T. Kress, M.K. Hudson, K.L. Perry et al.: Geophys. Res. Lett.31 (2004) L04808.Google Scholar
- [10]M.J. Birch, J.K. Hargreaves, A. Senior et al.: J. Geophys. Res.110 (2005) A07721.Google Scholar
- [11]J.M. Weygand and J. Raeder: Ann. Geophys.23 (2005) 1441.ADSCrossRefGoogle Scholar
- [12]N.A. Tsyganenko and M.I. Sitnov: J. Geophys. Res.110 (2005) A03208.Google Scholar
- [13]J. Kaššovicová and K. Kudela: Preprint, Inst. Exper. Phys., Slovak Acad. Sci., Košice, Slovakia, 1995, p. 45.Google Scholar
- [14]P. Bobik: PhD dissertation, P.J. Šafárik University, Košice, Slovakia, 2002.Google Scholar
- [15]K. Kudela and I.G. Usoskin: Czech. J. Phys.54 (2004) 239.CrossRefADSGoogle Scholar
- [16]http://nssdc.gsfc.nasa.gov/space/model/magnetos/data-based/modelling.htmlGoogle Scholar
- [17]http://www.ngdc.noaa.gov/IAGA/vmod/igrf.htmlGoogle Scholar
- [18]D.J. Cooke, J.E. Humble, M.A. Shea et al.: Nuovo Cimento14 (1991) 213.CrossRefGoogle Scholar
- [19]K. Kudela and M. Storini: in ESA SP-477, 2002, p. 289.Google Scholar
- [20]http://swdcdb.kugi.kyoto-u.ac.jp/Dstdir/Google Scholar
- [21]P.R. Boberg, A.J. Tylka, J.H. Adams et al.: Geophys. Res. Lett.22 (1995) 1133.CrossRefADSGoogle Scholar
- [22]http://coronas.izmiran.rssi.ru/F/instrumentsGoogle Scholar
- [23]V.D. Kuznetsov: Solar System Res.39 (2005) 433.CrossRefADSGoogle Scholar
- [24]S.N. Kuznetsov, K. Kudela, S.P. Ryumin et al.: Adv. Space Res.30 (2002) 1857.CrossRefADSGoogle Scholar
- [25]S.N. Kuznetsov, K. Kudela, I.N. Myagkova et al.: Indian J. Radio Space Phys.33 (2004) 353.Google Scholar
- [26]S.N. Kuznetsov, I.N. Myagkova, S.P. Ryumin et al.: J. Atmos. Solar-Terr. Phys.64 (2002) 535.CrossRefADSGoogle Scholar
- [27]N.A. Tsyganenko: Planet. Space Sci.37, No. 1, (1989) 5.CrossRefADSGoogle Scholar