M.Nechaeva,nech@nirfi.sci-nnov.ru

Radiophysical Research Institute, Nizhni Novgorod, Russia

Radio interferometer signal at raying of the solar wind plasma by cosmic source radio emission

This work is devoted to investigations of solar corona and solar wind irregularities by the method of radio probing with using of radio interferometer. The analysis of the radio interferometric signal allows to get information about physical characteristics of propagation medium at reception of the noise emission from a natural radio source. We represent the theoretical calculation of power spectrum of interferometric response to radio source emission, past through the turbulent medium.

This work is supported by grants RFBR №-02-02-39023 GFEN, INTAS N2000-0752.

1

2

,1 0

,2 0

,

,

,

*r t

r t

r t i

E r t E e

E r t E e

e e

*( ) ( , ) ( , )* r E r t E r t

Staraya Pustyn, RT-14, Nizhni

Novgorod

Puschino, RT-32, Moscow

* *

( )

( , ) ( , ) ( ,*

) ( , )

R

E r t E r t E r t E r t

00

12

* iY R e d

The power spectrum of the interferometer signal:

*( ) ( , ) ( , )* r E r t E r t

The power spectra of interferometer signal( 27 Febuary 1995, =18 cm, Puschino - Bear Lakes (Russia))

Bear Lakes,

RT-64, Moscow

0

2exp 4 , , 1 cos 1 cosp uR A Z d d

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02p

AN c

Zimenki, RT-14, Nizhni Novgorod

,P F V ��������������������������������������������������������

"frozen-in" hypothesis:

spatial spectrum of fluctuations of electron-dencity:

0

0 0

2

22 2 20

2 2,

m

m

p

l

F e

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0 и lm – outer and inner scale of turbu-lence

p - the index of the spatial spectrum of electron-density fluctuations

V - solar wind velocity

The strong phase fluctuations:

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D

Y

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2

2 2

0

2эф

E

D V

l

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Ussuriysk, RT-70

The weak phase fluctuations:

0* 2

x

xV

( , ) 1D ��������������

0 0 0 0Y K Y

0 0: II ( )mV V V ����������������������������

( 1)2 2

2 20 00 0 0

1 1

2 28 1 cos

2

p

x

x x x

pZ

Y ApV V V

Svetloe, RT-32, Saint-Petersburg

Experiment name: INTAS 99.4Bear Lakes, HartRAO, Noto, Puschino, Shanghai, Svetloe.date = 02-04 dec.1999

NRAO530Bear Lakes, Svetloe

The results of VLBI-experiments on the radio-raying of circumsolar plasma

0* 2

x

xV

fн= 700 кГц - signal frequency; fd =60 Hz- frequency of sampling 60 Hz, t=180-1800 sec

Acoustic experiment on sounding of turbulent water stream in hydrodynamic pool

b=34.5 см, V=1.01 м/с

p=2.9

b=34.5 см, V=1.84 м/с

p=3.3

CONCLUSION In this work the theoretical calculation of spectral response of the interferometer to cosmic radio source emission passed through turbulent plasma of solar wind was performed. The analysis showed that at the weak phase disturbances the output interferometer signal carries information about spatial spectrum of fluctuations electron-density and solar wind velocity. Mathematical simulation of experiments on turbulent media sounding shows good agreement between real observations and theoretical calculations.

This work is supported by grantsRFBR №-02-02-39023 GFEN,INTAS N2000-0752.

Staraya Pustyn, RT-14, Nizhni NovgorodYoung scientist at the solar wind observations

Staraya Pustyn, RT-14, Nizhni NovgorodVery young scientists at the solar wind observations

References

• Altunin V.I., Dementiev A.F., Lipatov B.N., Nechayeva M.B., Snegirev S.D., Tikhomirov Yu.V., Okmiansky V.A. (2000): Investigations of irregularities of the solar wind plasma by using the VLBI-method on the wavelengths 18 and 90 cm./Radiophysics and Quantum Electronics.Vol.43, No. 3, 178 (2000).

• V.G.Gavrilenko, B.N.Lipatov, M.B.Nechayeva. Analysis of the VLBI-system response to the emission from a radio source, propagated through the circumsolar plasma. /Radiophysics and Quantum Electronics. Vol. 45, No. 6, 2002, p.419-430.

• M.Nechayeva, V.Gavrilenko, B.Lipatov. Influence of solar wind plasma on VLBI output signal at reception of cosmic source radiation. /Proc. 10th. European Solar Physics Meeting, 'Solar Variability: From Core to Outer Frontiers', Prague, Czech Republic, 9-14 September 2002 (ESA SP-506, December 2002), p.55

CONCLUSION In this work the theoretical calculation of spectral response of the interferometer to cosmic radio source emission passed through turbulent plasma of solar wind was performed. The analysis showed that at the weak phase disturbances the output interferometer signal carries information about spatial spectrum of fluctuations electron-density and solar wind velocity. Mathematical simulation of experiments on turbulent media sounding shows good agreement between real observations and theoretical calculations.

This work is supported by grantsRFBR №-02-02-39023 GFEN,INTAS N2000-0752.