Heliosphericmodulationof cosmic rays

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1 Heliosphericmodulationof mic rays Agnieszka Gil M.V. Alania, K. Iskra, R. Modzelewska, M. Siluszyk, A. Wawrzynczak Siedlce University Kraków, Astrofizyka cząstek w Polsce, IX 207

2 Outline Themaincharacter-ourSun Hale cycle consisting of two successive -yearsacyclegcr Recurrent galactic mic rays intensity variation 3-4 CRP Forbush decreases Anisotropy of GCR GLE

3 Sun galactic sources extragalactic Our Region ( particle per km 2 -year) CERN Courier, Jan 29, 999 Energy (ev) 3

4 A<0 A>0 27-days averaged data, , of GCR by OuluNMandSSN Modulation parameter Usoskin, et al., 207

NMDB stations by Askar Ibragimov, 2008 http://www.nmdb.

5 NMDB stations by Askar Ibragimov, The effective energy is found as 2 GeV/nucfor the standard polar neutron monitor Asvestari, et al., 207

6 Temporal changes of the GCR intensity observed by Oulu NM Monthly smoothed SSN The strengthb of the HMF Rigidity exponent gamma of the GCR intensity variation Siluszyk et al., 205 6

7 Power Spectral Density (PSD) of the HMF s turbulence ν α PSD f ν The rigidity spectrum exponent the isotropic intensity variations of GCR α Diffusion A Κ α R γ ( α ) = 0.96 α γ ( R) γ ( R) R D D 7

8 Temporal changes of the amplitude of the long period variation and approximated observed changes of the GCR intensity (dotted line). Model the solution of the PDEfor the rigidity of 0 GV (solid line) in period Siluszyk et al., 207; Siluszyk et al., 20 Temporal changes of the amplitude of the long period variation and approximated observed changes of the GCR intensity (dotted line). Model the solution of the PDEfor the rigidity of 0 GV (solid line) in period

9 f res 300 = 2π U B R SW Yearly alternations of the resonant frequency for rigidities 0 GV of GCR protons in ; (a) the solid line B and U sw changeable, (b) the dotted line B changeable and U sw is constant, and (c) the dash line U sw changeable and B is 9 constant with the cycle of SA. Siluszyk et al., 205

6750 Oulu [count rates] 6700 6650 6600 6550 6500 06.09.2007 30.0.2007 23.2.2007 5.02.2008 09.04.2008 02.

10 6750 Oulu [count rates] Daily data, , of the GCRs by Oulu NM (micrays.oulu.fi)

Mursula, 207 3-year means of amplitude of the st and the

11 3-year running means of yearly averaged amplitudes of the st and the 2nd harmonics of GCR for Oulu NM Gil, Mursula, year means of amplitude of the st and the 2nd harmonics for the last five solar minima with linear trend

12 D( R) AR γ for = D( R) 0 for R R Rmax > Rmax Dorman, 963; Ahluwalia, Ericksen, 97; Yasue et al., 982 The changes of the rigidity spectra exponent γ of the 27-days variation of the GCR intensity calculated ug Kiel and Rome neutron monitors in (smoothed over 39 Carrington rotations). Gil, Alania, 206

13 The 3-4 CRP quasi-recurrence A27 of GCR [%] A27 of GCR [%] 0.3 CR Sequences of the 3-4 CRP(three to four Carrington rotations period) in (maximum epoch of SA) and in (minimum of SA) of amplitudes of the 27-day variation of the GCR intensity by Kiel NM Gil, Alania, 20; CR 02

14 November 5-9, 2004 Smoothed over 3 days temporal changes of the GCR intensity for the NMs and Nagoya muon telescope channels during Fd. Temporal changes of the rigidity spectrum exponent based on the data of the stations divided in twogroups according to their cut off rigidities for lowrc<4 GV, and highrc>8 GV cut off rigidities Rc>8 GV Hale, Mexi, N0VV, NEE, N3EE, N4NE, N4SE Rc<4 GV Calg, Caps, Kerg, McMu, Oulu, Sopo (Wawrzynczak&Alania 205 J. Phys.: Conf. Ser )

15 Background We have showed (e.g. Wawrzynczakand Alania 2005, 2008, 200) that the changes of the rigidity R spectrum D(R)/D(R) R -γ of the Fdsdetermined by NMsand ground MTdata,are related with the changes of the PSD of the IMF s turbulence (PSD f - ν, f is a frequency) Particularly exists a relationship γ 2 - ν We consider that this relationship exists owing to the dependence of the diffusion coefficient K of GCR particles on the rigidity R according to the quasi linear theory (QLT) K R 2 ν [Jokipii, 966; Hasselman and Wibberentz, 968 Jokipii, 97, Toptygin, 985],

16 Running PSD, November 2004 The values of the exponent νof the PSD for HMF components based on the 2 days running series of hourly datain October, 24 November, 29, 2004 (Wawrzynczak&Alania 205 J. Phys.: Conf. Ser )

17 γ 2 - ν November5-20, 2004 Temporal changes of the exponent γand νduring Fd in November 3-0, 2004 (Wawrzynczak&Alania 205 J. Phys.: Conf. Ser ) Correlation Coefficient ν_bx ν_by ν_bz γ Rc>8 GV -0.88± ± ±0.0 γ Rc<4 GV -0.57± ± ±0.03

18 PSD Bz, November 3-7, 2004 ν low freq < ν high freq νlow freq < νhigh freq The PSD for IMF componentbzbased on the 2 days running series of hourly datain November2004 (Wawrzynczak&Alania 205 J. Phys.: Conf. Ser )

19 Ahluwalia, Ygbuhay, Modzelewska, et al., JGR-Space Physics, 205: Yearly λ Gr (%) for NM, NM2 in Yearly α for NM, NM2 in

20 Ahluwalia, Ygbuhay, Modzelewska, et al., JGR-Space Physics, 205: Yearly Gr for NM, NM2 for and 3y moving average (red). A scatter plot of Gr (%/AU) versus B (nt)

changes of the amplitudes of the 27-day variation of the GG index and At component of the 3D anisotropy

21 Modzelewska and Alania, AA, 207, submitted: Temporal changes of the average A27Asmoothed over 3 solar rotations for 6 NMs (Moscow, Kiel, Oulu, Deep River, Climax) in during A>0 and A<0 Temporal changes of the amplitudes of the 27-day variation of the GG index and At component of the 3D anisotropy (top) and By component of the HMF (bottom) smoothed over 3 Sun's rotations during A>0 and A<0 polarity epochs.

22 The strong GLE events (the strength I > 00 %*hr) are characterized by a hard spectrum Increasemeasured by Leeds and OttawaNMs, during the GLE5. Leeds NM registered the highest peak increase (56 %),Ottawa NM detected the most intense integral response (5300 %*hr). Asvestari, et al., 207

Kij ( ) s f ( U + v ) = 2 3 2 22 32 3 23 33 dr f + B = arctg B 3 r ϕ Up Krymsky, 964;

23 Kij ( ) s f ( U + v ) = dr f + B = arctg B 3 r ϕ Up Krymsky, 964; Parker, 965 f p Ωrθ = arctg U =, = f t B = arctg θ B r = d Jokipii, Levy and Hubbard, 977

24 Tensor ( ) [ ] ( ) [ ] ( ) [ ] ( ) [ ] ( ) [ ] ( ) [ ] ( ) [ ] ( ) [ ] [ ] = = + = + = + + = + = = = + + = [Alania 978; 2002] /s cm 0 ) ( ),, ( = ϕ θ ρ R

25 Stochastic approach: Backward in time Forward in time Wawrzynczak, Modzelewska& Gil, 205 Gardiner, 2009

26 Trajectories of the pseudoparticles with rigidity 0 GV. The specific colors highlight the trajectories of the sample pseudoparticles tracedbackward in time from the heliosphere boundary until they reach r = AU, θ = 90,ϕ = 80.

27 Changes of the expected amplitudes of the 27-dv of the GCR intensity at the Earth s orbit for the rigidity of 0 GV based on the solutions of the Parker transport equation by SDEs and FDM in comparison with the GCR intensity registered by Moscow neutron monitor for the 7 September- 3 October Wawrzynczak, Modzelewska & Gil, 205 U ( ϕ + 6.0) ( 2ϕ ) 0.0( 3.04)) = U0 ( 0.3 ϕ

28 . Global network of neutron monitors may be a useful tool for some indirect solar observations. 2. The rigidity spectrum of the -year variations of the GCR intensity is hard in the minimum epochs of SA (γ 0.6) when the exponent ν y of the PSD of HMF is higher (ν y ~.9), and is soft in themaximumepochs(γ.2),when ν y isrelativelylower(ν y ~.4). 3. We show the existence of clearly established quasi-periodicity with duration of three to four Carrington rotations period (3-4 CRP) in the changes of the amplitudes of the 27-day variations of GCR intensity, parameters of solar wind and solar activity. The 3-4 CRP recurrence is shaped by the combined: solar dynamo and differential rotation. 4. The A27 and A4 amplitudes during the SC minima depict a declining trend, which is associated with the weakening in the solar polar magnetic fields during the last four solar cycles. 5. The Fd rigidity spectrum exponent γ is the larger the higher are cut off rigidities of stations used in calculations. The dependence of the exponent ν of the PSD of the HMF turbulence upon frequency during Fd confirms the relationship between exponent γ and exponent ν 6. Solar anisotropy calculated from NMs data gives the opportunity to estimate the heliospheric modulation parameters: e.g., density gradients and diffusion coefficients used in modeling Conclusions

29 References: Ahluwalia, H. S., Ygbuhay, R.C., Modzelewska, R., Dorman, L.I., Alania, M.V., Journal of Geophysical Research: Space Physics, 20, , 205 M.V. Alania, K. Iskra, M. Siluszyk, Adv. Space Res., Volume 45, Issue0,203-20, 200. Asvestari, E.; Willamo, T.; Gil, A.; Usoskin, I. G.; Kovaltsov, G. A.; Mikhailov, V. V.; Mayorov, A., Advance Space Research, 60, 4, , 207 Gil, A.; Mursula, k., Astronomy& Astrophysics, 599, id.a2, 6 pp., 207 Gil, A.; Alania, M. V., Solar Physics, 29, 6, , 206 Gil, A.; Alania, M. V., Solar Physics, 278, 2, , 202 Gil, A.; Alania, M. V., Journal of Atmospheric and Solar-Terrestrial Physics, 73, 2-3, , 20 Iskra K., Siluszyk M., Alania, M.V, Journal of Physics: Conference Series , 205 Modzelewska, R. Alania, M.V., Astronomy & Astrophysics, 207, submitted Siluszyk M., Iskra K., Alania, M.V., Miernicki S., Journal of Geophysical Research Space Physics (in press) 207 Siluszyk M., Iskra K., Alania, M.V Journal of Physics: Conference Series 632, 02080, 205 SiluszykM., IskraK., Alania, M.V., Solar Physics, 289,, , 204 Siluszyk, M. Wawrzynczak, A. Alania, M.V., Journal of Atmospheric and Solar-Terrestrial Physics, Volume 73, , 20 Usoskin, I. G.; Gil, A.; Kovaltsov, G. A.; Mishev, A. L.; Mikhailov, V. V., Journalof GeophysicalResearch: Space Physics, 22, 4, , 207 Wawrzynczak, A.; Modzelewska, R.; Gil, A., Journal of Physics: Conference Series, 632,, article id , 205 Wawrzynczak, A.; Modzelewska, R.; Gil, A., Journal of Physics: Conference Series, 574,, article id , 205 Wawrzynczak and M V Alania, Journal of Physics: Conference Series, 205, , 632, 02083, ECRS204

30 Thankyou! Acknowledgements Investigators of NMs. SSN, SW and SA data are from This work was supported by the Polish National Science Centre (DEC-202/07/D/ST6/02488& DEC-206/22/E/HS5/00406)

The connection of the interplanetary magnetic field turbulence and rigidity spectrum of Forbush decrease of the galactic cosmic ray intensity

Journal of Physics: Conference Series PAPER OPEN ACCESS The connection of the interplanetary magnetic field turbulence and rigidity spectrum of Forbush decrease of the galactic cosmic ray intensity To