ROCKENBACH, M.1; DAL LAGO, A.2; MUNAKATA, K.3; KATO, C.3; KUWABARA, T.4; BIEBER, J.4; SCHUCH, N.J.5; DULDIG,

M.L.6; HUMBLE, J.E.6; AL JASSAR, H.K.7; SHARMA, M.M.7 and SABBAH, I.8,9

1Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraíba, São José dos Campos - SP, Brazil;2National Institute for Space Research (INPE-MCT), São José dos Campos – SP, Brazil;

3Department of Physics, Shinshu University, Matsumoto, Japan; 4Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, USA;

5Southern Regional Space Research Center (CRS/CCR/INPE-MCT), Santa Maria, RS, Brazil; 6School of Mathematics and Physics, University of Tasmania, Hobart, Australia;

7Physics Department, Kuwait University, Kuwait 13060.;8Department of Natural Sciences, Collage of Health Sciences, the Public Authority of Applied Education and

Training, Kuwait;9Department of Physics, Faculty of Science, University of Alexandria, Alexandria, Egypt.

• ~85 % protons• ~10 % helium nuclei• a few % heavier nuclei• ~1 % electrons

Observables• Energy spectrum• Elementary & isotopic compositions• Isotropic intensity

(GCR density)• Anisotropy

(GCR streaming)

Anchordoqui, L., et al., IJMP (2003)

E-2.7

Bending here is due to the solar modulation which varies in solar cycle

• Ground-based detectors measure byproducts of the interaction of primary cosmic rays (mostly protons) with Earth’s atmosphere.

• Neutron monitor detects neutrons produced by elastic scattering from atmospheric nuclei.

• Muon detector measures muons produced by inelastic (strong) interaction.

Neutron monitor

Muon detector

Air shower array

E1ry (GeV) = 50~100, 1~30

observations ofinner heliosphere & space weather

: GCR density (omnidirectional intensity)

: streaming

: anisotropy

SW convection diffusion

Adiabatic cooling

Anisotropy ( ) tells us the spatial gradient (

)

which reflects the magnetic field geometry

Reverses with B polarity 22y variation, T/A dependence

drift velocity

curvature drift gradient drift

drift streaming

Difusion tensor

AA

AA

TT

TT

V/ ~ 5AU

Solar wind V

BNeutra

l Sheet

(Current sheet)

Solar windsource surface

Away

Toward

B

Wavy neutral sheet

Ballerina’s skirt

A<0 (Negative)Ω

B

M

TS

NS

B

A>0 (Positive)Ω

B

M

TS

NS

B

Away

TowardAway

TowardA > 0A < 0

neutral s

heet

neutral sheet

• Reproduces the solar cycle variation of GCR density from the variation of NS tilt-angle.

• Predicts local minimum (maximum) of GCR density on the NS for A>0 (A<0).

G

G

（ solar magnetic dipole reverses every 11 years ）

N

S

S

N

N

S

S

N

S

N

• However, this is only the variation of GCR density.• GCR wind also tells us the GCR gradient in 3D as a function of

time.

Kaz. Munakata1, C. Kato1, S. Yasue1, J. W. Bieber2, P. Evenson 2, T. Kuwabara 2,M. Rockenbach3, A. Dal Lago 4, N. J. Schuch 5, M. Tokumaru 6, M. L. Duldig 7, J. E. Humble

7,I. Sabbah 8,9, H. K. Al Jassar 10, M. M. Sharma 10

15 researchers from 10 institutes in 6 countriesworking with 4 muon detectors in operation at…

1 Shinshu University, JAPAN 2 Bartol Research Institute, USA 3 UNIVAP, BRAZIL 4 INPE, BRAZIL 5 CRS/INPE, BRAZIL

6 STE Laboratory, JAPAN 7 University of Tasmania, AUSTRALIA 8 College of Health Science, KUWAIT 9 Alexandria University, EGYPT 10 Kuwait University, KUWAIT

GMDN collaboration

Global 　 Muon 　 Detector 　Network(GMDN)

Nagoya (1969)36m2

171h

0,15

Hobart(1992)

9m2

131h0,3

Prototipe (2001)

Expansion I (2005)

Expansion II (2012)

4m2 28m2 36m2

9 17 17

1h 1, 10 e 60 min 1, 10 e 60 min

0,34 0,2 0,15

Kuwait(2006)

30 proportional counters5m length 10cm diameter

9m2, 13,1h, 0,32

Global 　 Muon 　 Detector 　Network(GMDN)

São Martinho da Serra

• ○□△display the asymptotic viewing directions of median energy cosmic rays corrected for the geomagnetic bending.

• Thin lines indicate the spread of viewing direction for the central 80 % of the energy response to

primary CRs.

0,1

1,1

1,1

1,1

1,1

0,00,

)(

)sincos)((

)sincos)((

)( )(

jiz

ijiijiy

ijiijix

jifitji

ct

tctst

tstct

ctItI

Cosmic Ray Density

(2) Normalization

(3) Best-fit for cosmic ray density and anisotropy vector.

)()(

)()( ,

,

1,1, tI

tI

tItI obs

jiji

corrji

Data are normalized in relation to Nagoya vertical channel.

mjin

mjin sc ,,,, , : coupling coefficient

: 24 hour running average for jth channel of ith detector

)(, tI ji

)(1,1 tI : 24 hour running average for Nagoya (i=1), Vertical channel (j=1)

Anisotropy vector

(1) Barometric effect correction; pI

I

We derive which minimize ….

11%

(%)

-5

-4

-3

-2

-1

0

1

248 250 252 254 256

Nagoya V (60GeV)

Misato V (145GeV)

Sakashita V (331GeV)

SSC (01:39UT 9/9 1992)

“Loss-cone” precursor(Nagashima et al., 1992)

Doy of 1992

Dorman et al. (2003)

“Loss-cone” precursor(Nagashima et al., 1992)

Dorman et al. (2003)

Rockenbach et al. GRL, 38, 2011

Loss cone(deficit)

Enhanced Varianceshock reflection

(excess)

CR

cy

lind

er

Magnetic flux rope

• Muon detectors measure muons produced by the interaction of high-energy (E > 1 GeV) primary cosmic rays (CRs) with the atmospheric nuclei.

• Due to the high longitudinal momentum transfer to muons, their incident directions well preserve the incident direction of primary CRs ⇒ the multidirectional muon detector.

• GMDN is a network of four muon detectors in Japan, Brazil, Australia, Kuwait, and capable for measuring CR intensities from many directions simultaneously.

• We measure the CR streaming and CR precursors accurately with the GMDN and deduce the large-scale magnetic structure in the Space Weather:

The precursor is seen as the deficit intensity of CRs arriving from the sunward IMF: loss-cone (LC) precursor

CRs reflected and accelerated by the approaching shock are also observed as an excess intensity: enhanced variance precursory excess.

• This is an alternative study, where we can estimate the arrival time of ICME using ground-based measurements.