ULF-Sounding of Magnetosphere and Earth - Hydromagnetic Waves in the Magnetosphere and the Ionosphere - page 324

3

q=1.15

2.8

(1)

(2)

/f r

f r

2.6

l 2 (q,w 0 =0.8767)

2.4

2.2

2

0 1 2 3 4 5 6

q

Fig. 11.2. Graphic calculation of (11.12)

concentration at the top of the field line n 0 j = 106 /Ω j L j 2 = 226 . 9 , 273 . 7 ,
321 . 2 , 390 . 3cm − 3 . The parameters a and s of the power approximation
(11.9) of the equatorial plasma density distribution are found from (11.18)
as a =3 10 3 cm − 3 , s =1 . 767 .

The dependence of n 0 on the geomagnetic latitude is shown in Fig. 11.3.
The solid circles in Fig. 11.3 are calculated according to (11.15). The approx-
imation (11.9) is shown with the line.
The obtained values of plasma concentration n 0 , and the parameters q and
s are in good agreement with those obtained from the satellite and whistler
measurements under weak and moderate geomagnetic activity at L = 3-4
(e.g., [11], [27], [31]). The analysis of the accuracy of the estimates of plasma
density with hydromagnetic diagnostics [15] shows that the accuracy of this
method is close to that of whistler measurements [28]. Besides, the MHD-
diagnostics combined with whistler measurements allow us to estimate the
concentration of heavy ions in the magnetosphere.

×

11.3 Ground-Based Magnetotelluric Sounding

Impedance

The horizontal electric and magnetic field components on the ground are
linked by a linear operator Z which is a functional from the distribution of
the ground conductivity σ g ( r ). For a layered medium providing the basis
for the magnetotelluric model, operator Z can be written in the form of an
integro-differential transformation. The kernel G of the operator by virtue of