All Figures

$\begin{figure} \par\includegraphics[width=8cm,clip]{2774fig1.eps} \end{figure}$ Figure 1: Total flux time profiles of the event 2000 January 12, obtained by the Nobeyama radiopolarimeter (NoRP) at 9.4, 17, 35 GHz.
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In the text

$\begin{figure} \par\includegraphics[width=7.6cm,clip]{2774fig2.eps} \end{figure}$ Figure 2: The NoRP frequency spectrum at the time of the microwave burst peak 01:36:13 UT.
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In the text

$\begin{figure} \par\includegraphics[width=7.9cm,clip]{2774fig3.eps} \end{figure}$ Figure 3: The averaged correlation amplitude $\rho (t)$ of the signals recorded by NoRH at 17 GHz a) and 34 GHz c) and relative variations of the signal, $\Delta \rho /\rho = (\rho (t)-\rho _0)/\rho _0$ , corresponding to the modulation depth at each frequency b), d).
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In the text

$\begin{figure} \par\includegraphics[width=7.3cm,clip]{2774fig4.eps} \end{figure}$ Figure 4: Fourier spectra of the relative variations $\Delta \rho /\rho = (\rho (t)-\rho _0)/\rho _0$ of the NoRH correlation amplitude signal in the interval $\pm 40$ s about 01:36:20 UT at 17 and 34 GHz. The spectra show the presence of at least two well pronounced spectral components, with the periods 14-17 s and 8-10 s.
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In the text

$\begin{figure} \par\includegraphics[width=7.9cm,clip]{2774fig5.eps} \end{figure}$ Figure 5: Radio images made at the flare maximum at 01:36:15 UT at 34 GHz (filled pixels) and 17 GHz (dotted contour curves, the contour levels are 0.7, 0.85 and 0.98 of the maximum brightness temperature T_B17). The black contour shows the positioning of the HXR sources, obtained in the channel L (13.9-22.7 keV) of Yohkoh/HXT. The HXR signal had been integrated over the time interval 01:35:52-01:36:15 UT, the contours correspond to the levels 0.2, 0.4, 0.6 and 0.9 of the maximum value.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{2774fig6.eps} \end{figure}$ Figure 6: The time profiles $\Delta F/F$ measured at 17 GHz for the three different regions of the size $10\hbox {$^{\prime \prime }$ }\times 10\hbox {$^{\prime \prime }$ }$ : the Southern (panel a)) and Northern c) legs of the loop, and the loop apex b) determined as the centre of the radio source detected at 34 GHz. The Fourier spectra of these time profiles are shown in plots d)- f), respectively. The spectra show that there are both the 8-11 s and 14-17 s spectral components everywhere in the loop, the shorter period component dominates at the legs ( d) and f)), while the longer period component - at the apex e).
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{2774fig7.eps} \end{figure}$ Figure 7: The phase evolution near the burst maximum at 01:36:00 UT for the two spectral peaks of oscillations: P₁=16 s and P₂=9 s. The phase of oscillations for the loop top source is shown by the solid line, and for the northern (Foot 2) and southern (Foot 1) leg sources by the dotted and dashed lines, respectively. The phase shift between oscillations from the loop top and foot sources is well pronounced for the P₂ spectral component and is very small for the P₁component.
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In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{2774fig8.eps} \end{figure}$ Figure 8: Left panels: convolved and integrated radio fluxes coming from the $10\hbox {$^{\prime \prime }$ }\times 10\hbox {$^{\prime \prime }$ }$ boxes situated at the centre of the Northern HXR source (the loop footpoint, panel a), at the centre of the 34 GHz source (panel b)) and at the region 20 $^{\prime \prime }$ eastward, i.e. over the loop (panel c)). Right panels: the time profiles of the spectral indices $\alpha$ , calculated as $\alpha = \log(F_{34}/F_{17})/\log({34}/{17})$ , where F₃₄ and F₁₇are the fluxes measured at the 34 GHz and 17 GHz bands, which characterise the spectral steepness, are shown in panels d, e and f (the regions correspond to the time profiles shown in panels a), b) and c)).
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In the text

$\begin{figure} \par\includegraphics[width=8.4cm,clip]{2774fig9.eps} \end{figure}$ Figure 9: Comparison of observed fluxes at 17 and 34 GHz from the loop top (circles) and footpoint (crosses) source with $10\hbox {$^{\prime \prime }$ }\times 10\hbox {$^{\prime \prime }$ }$ area and the corresponding microwave spectra calculated for the sources of the same size. The plasma density is assumed constant along the loop, $n_0=8\times 10^{10}~$ cm^-3, the magnetic field is 100 G and 200 G in the loop top and footpoint sources, respectively. The electron power law spectral index is $\delta =3.0$ , the number density of energetic electrons in the loop top is $n_{\rm lt}(E>1~\rm MeV)=6.1\times 10^4~$ cm^-3 and near the footpoint $n_{\rm fp}(E>1~\rm MeV)=2.3\times 10^3~$ cm^-3.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{2774fig10.eps} \end{figure}$ Figure 10: a) Distribution of plasma density (dot-dashed) and high energy electrons (dotted line). The maximum value of number densities of plasma and energetic electrons are taken the same as for the loop top source (Fig. 9). b) Intensity spatial profiles across the top part of a model flaring loop. The displacement of 17 (solid line) and 34 GHz (dashed line) intensity maxima due to Razin suppression of 17 GHz emission near the loop axes is clearly seen.
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In the text

$\begin{figure} \par\includegraphics[width=7.9cm,clip]{2774fig11.eps} \end{figure}$ Figure 11: Phase speeds of MHD modes of a straight magnetic cylinder as function of the longitudinal wave number normalised by the cylinder radius a, for $C_{\rm A0} = 600$ km s^-1, $C_{\rm Ae}=3300$ km s^-1, $C_{\rm s0} = 340$ km s^-1 and $C_{\rm se} = 200$ km s^-1. Solid curves correspond to sausage (m=0) modes of different radial numbers ( l=1, 2, 3, ...), dotted curves to kink (m=1) modes, dashed and dashed-dotted curves - to the ballooning modes m=2 and m=3, respectively. For fast modes, the lowest phase speed curves of each line style correspond to the l=1 mode. Horizontal straight lines show the characteristic speeds mentioned above. The hatched region shows where no trapped mode can exist.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{2774fig1.eps} \end{figure}$	Figure 1: Total flux time profiles of the event 2000 January 12, obtained by the Nobeyama radiopolarimeter (NoRP) at 9.4, 17, 35 GHz.
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$\begin{figure} \par\includegraphics[width=7.6cm,clip]{2774fig2.eps} \end{figure}$	Figure 2: The NoRP frequency spectrum at the time of the microwave burst peak 01:36:13 UT.
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$\begin{figure} \par\includegraphics[width=7.9cm,clip]{2774fig3.eps} \end{figure}$	Figure 3: The averaged correlation amplitude $\rho (t)$ of the signals recorded by NoRH at 17 GHz a) and 34 GHz c) and relative variations of the signal, $\Delta \rho /\rho = (\rho (t)-\rho _0)/\rho _0$ , corresponding to the modulation depth at each frequency b), d).
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$\begin{figure} \par\includegraphics[width=7.3cm,clip]{2774fig4.eps} \end{figure}$	Figure 4: Fourier spectra of the relative variations $\Delta \rho /\rho = (\rho (t)-\rho _0)/\rho _0$ of the NoRH correlation amplitude signal in the interval $\pm 40$ s about 01:36:20 UT at 17 and 34 GHz. The spectra show the presence of at least two well pronounced spectral components, with the periods 14-17 s and 8-10 s.
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