Precursor signatures of storm sudden commencement observed by a network of muon detectors

Precursor signatures of storm sudden commencement observed by a network of muon detectors

C. R. BRAGA 1, A. DAL LAGO 1, M. ROCKENBACH 2 , N. J. SCHUCH 3, L. R. VIEIRA 1, K. MUNAKATA 4, C. KATO 4 , T. KUWABARA 5, P. A. EVENSON 5, J. W. BIEBER 5,

M. TOKUMARU 6, M. L. DULDIG 7, J. E. HUMBLE 7, I. S. SABBAH 8, H. K. AL JASSAR 9, M. M. SHARMA 9

1 National Institute for Space Research, São Jose dos Campos, Brazil2 Universidade do Vale do Paraíba ,São Jose dos Campos, Brazil3 Southern Regional Space Research Center, Santa Maria, Brazil

4 Physics Department, Shinshu University, Matsumoto, Japan5 Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, USA

6 Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, Japan7 School of Mathematics and Physics, University of Tasmania, Tasmania, Australia

8 Department of Natural Sciences, College of Health Sciences, the Public Authority of Applied Education and Training, Kuwait - Department of Physics, Faculty of Science, Alexandria University, Alexandria, Egypt

9 Physics Department, Faculty of Science, Kuwait University, Kuwait City, Kuwait

E-mail: [email protected]

2Detectors photographs (except Sao Martinho da Serra): private communication with Prof. K. Munakata, 2010 and Prof. I. Sabbah, 2011Background source: http://earthsatellitemaps.com/wp-content/uploads/2009/06/mapofearth.jpg, 2010

Global Muon Detector Network (GMDN)

São Martinho da Serra

Kuwait

Hobart

Nagoya

4 x 7

6 x 6

3 x 3 (4 x 4)

3 x 3

Source: Yashin et al. (2006).

Methodology

- Pressure effect correction;- Temperature effect correction;- Trailing moving average;- First order anisotropy;- Normalization by statistical error.

Objective

To study the possibility of observing cosmic ray precursors of a weak geomagnetic storm registered in November 24th 2008 with storm sudden commencement (SSC) at 23:51 UT.

Negative temperature effect

ΔHβN=ΔN TT

TEDNOTCORRECTCORRECTEDETEMPERATUR ΔNN=N _

∆H: deviation of the altitude of 100 hPa

Correlation=-0.95

Dev(%)=-5.9 (%/km) ∆H (km) + 97%∙

Dev

iatio

n N

a V(

%)

Altitude (km) of 100 hPa layer

Temperature effect correction

Correlation=-0.95

Nagoya: α≥ 0.95-6.7 ≤ β ≤ -5.9 %/km

São Martinho da Serra : α≥ 0.49-4.8 ≤ β ≤ -3.7 %/km

Hobart: α≥ 0.72-5.0 ≤ β ≤ -3.6 %/km

Kuwait: α≥ 0.89-7.3 ≤ β ≤ -6.1 %/km

Dev(%)=-5.9 (%/km) ∆H (km) + 97%∙

Dev

iatio

n N

a V(

%)

Altitude (km) of 100 hPa layer β: regression coefficient (slope)α: correlation coefficient

High-altitude measurements sites

High-altitude pressure measurements sites

Muon stationApprox. distance

(km)NameGeographic coordinates

(degrees)

Shionomisaki 33.5 N; 140.1 E

Nagoya

200

Tateno 36.0 N;140.1 E 400

Wajina 37.4 N; 136.9 E 300

Porto Alegre 30.0 S; 308.8 E São Martinho da Serra 260

Kuwait 29.2 N; 48.0 E Kuwait 10

Hobart 42.8 S; 147.5 E Hobart 30

Day of year (2008)

Day of year (2008) Day of year (2008)

Day of year (2008)

Seasonal temperature effect correctionKu

wai

t Dev

(%)

Nag

oya

Dev

V(%

)

Hob

art D

ev V

(%)

SMS

Dev

V(%

)

NORTH HEMISPHERE SOUTH HEMISPHERE

SUMMERWINTER WINTER

SUMMERWINTER WINTER

SUMMER

SUMMER

SUMMER

SUMMER WINTER

WINTER

Trailing moving average (TMA)

24

)()(

,23

,

tItr

ji

t

tji

TMA of the reference directional channel (i=1) of the reference station (j=1)

Uncorrected data

Corrected data Directional ChannelStation

10

Removing spurious diurnal variation

(following Kuwabara et al., 2004; Okazaki et al., 2008)

Pitch angle calculation

)()()( ,, ttt jiji

)(, tji

)(, tji

)(tPitch angle

IMF direction

SUNSUN

B

0, ji

180, ji

Asymptotic direction of view of the i-th directional channel of the j-th station

EARTH

11

First order anisotropy

1⋮1 0⋮0 0⋮0 0⋮0 cos𝜒1,1(𝑡)⋮cos𝜒1,13(𝑡)

0⋮0 1⋮1 0⋮0 0⋮0 cos𝜒2,1 (𝑡)⋮cos𝜒2,13(𝑡)

0⋮0 0⋮0 1⋮1 0⋮0 cos𝜒3,1(𝑡)⋮cos𝜒3,13(𝑡)

0⋮0 0⋮0 0⋮0 1⋮1 cos𝜒4,1(𝑡)⋮cos𝜒4,13(𝑡)

𝐽1,1𝑜𝑏𝑠(𝑡)⋮𝐽1,13𝑜𝑏𝑠(𝑡)

𝐽2,1𝑜𝑏𝑠(𝑡)⋮𝐽2,13𝑜𝑏𝑠 (𝑡)

𝐽3,1𝑜𝑏𝑠(𝑡)⋮𝐽3,13𝑜𝑏𝑠 (𝑡)

𝐽4,1𝑜𝑏𝑠(𝑡)⋮𝐽4,13𝑜𝑏𝑠 (𝑡)

𝐽10(t)

𝐽20(𝑡)

𝐽30(𝑡)

𝐽40(𝑡)

𝐽 1(𝑡)

Nagoya(i=1, j=1,2,…,13)

𝐽𝑖,𝑗𝑜𝑏𝑠

São Martinho(i=2, j=1,2,…,13

Kuwait(i=3, j=1,2,…,13

Hobart(i=4, j=1,2,…,13

52x152x5

5x1

: observed normalized deviation

)())(cos()()( ,,10 tJttJtJ obs

jijii i є [1,4] (detector)

j є [1,13] (directional channel)

)()()( 0,, tJtJtJ iobsji

calji

)(0 tJ i

)(1 tJ

: effects common for all directional channels but

different from one station to the other

: first-order anisotropy

: pitch angle (deg))(, tji

ResultsSystematic decrease for small pitch angles: loss cone signature!

The diameter is proportional to the magnitude.

Increase Decrease

SSC: 2011/11/24 23h51min

0.3%

Aver

age

devi

ation

(%

)

Aver

age

devi

ation

(%

)

Aver

age

devi

ation

(%

)

Aver

age

devi

ation

(%

)

Results

1-6 h before the SSC

6-11 h before the SSC

11-16 h before the SSC

16-21 h before the SSC

Average deviation (%) for all directional channels in 10-degree pitch angle regions in 5-hour periods in November 24th 2008.

Summary and conclusions

• This work illustrates a methodology for visualization of loss cones

signatures

• We used simultaneous observation of 4 multidirectional muon

detectors;

• Total number of directional channels: 60;

• Pressure and temperature effect were removed;

• Daily variation was removed by using a trailing moving average;

• Weak geomagnetic storm: the most difficult case to show the

precursors.

Acknowledgements

This work was partially founded by FAPESP under project number 2008-08840-0, by CNPq under projects 303798/2008-4 and 481368/2010-8. Thanks to CAPES through the Graduate Program in Space Geophysics. Radiosonde data has been provided by UKMO and BADC. Dst index data were provided by the World Data Center for Geomagnetism, IMF and plasma data by the ACE mission and Kp and SSC data by the Helmholtz Centre Potsdam German Research Centre for Geosciences.

References [1] T. Kuwabara et al., 2006, Space Weather, 4, S08001[2] D. Ruffolo et al., 1999, Proceedings of the 26th Int. Cosmic Ray Conf., 53.[3] L. I. Dorman: 1963 Geophysical and Astrophysical Aspects of Cosmic Rays, Prog. Phys., Cosmic Ray

Elementary Particles, North-Holland.[4] K. Nagashima et al., 1992, Planet. Space Sci., 40: 1109-1137[5] K. Munakata et al., 2000, J. Geophys. Res., 105 (A12): 27427-27468[6] K. Kudela; M. Storini, 2006, Adv. Space Res., 37(8): 1443-1449 [7] A. V. Belov et al., 2001, Proceedings of the 27th Int. Cosmic Ray Conf., 3507-3510[8] Y. Okazaki et al., 2008, Astrophys. J., 681: 693-707[9] A. Duperier, 1944, Terrestrial and Magnetic Atmospheric Electricity, 49: 1-7[10] A. Duperier, 1949, Proceddings of the Physical Society, 62: 684-696[11] P. M. S. Blackett, 1938, Phys. Rev. Let. 54: 973-974[12] S. Sagisaka, 1986, Il Nuovo Cimento, 9C: 4809[13] T. Kuwabara et al., 2004, J. Geophys. Res., 100: L19803.

Thank you!