SELF

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O.N. Karavashkina and S.B. Karavashkin

The presented model of circulation currents allows us to describe one more complex of observed phenomena. For it, let us draw our attention to two peculiarities. We already spoke of one of them - the circulation currents in the core and envelop will be directed oppositely (if we consider the currents in the view of conventions of electrical engineering as the motion of positive charges from plus to minus). This means, in fact we can model the star at the early stage of its evolution by two giant turns of inductance enclosed one into another and connected oppositely. And we should note that between the envelope and core there has formed a capacitor charged because of heating up to giant difference of voltage. Finally, we should note that there in the core usually occur turbulent processes producing powerful local fluctuations of charge, and when the envelope swells, they essentially change the potential on the "capacitor armatures". This can be modelled as a noise oscillator exciting the above electric circuit that consists of oppositely connected inductances and capacitance. General appearance of this circuit is shown in Fig. 2.20 (a). In Fig. 2.20 (b) is shown the same circuit, only some ordered.

Fig. 2.20. Electric model of star at the initial stages of its evolution.

We can see from Fig. 2.20 (b) that the described model corresponds to the circuit of sequential LC contour, but with the peculiarity that the excitation from one "armature" to another will take a considerable time interval that can be measured in minutes and even in hours (so in Fig. 2.20 (b) we showed just the low-frequency noise oscillator). Consequently, the period of resonance oscillations of such contour can be measured in hours and even in years. These oscillations will also effect on the star luminosity, as they will change the electric potential of envelope and cause the envelope pulsing in radial and tangential directions; this will change the density of gas in envelope and, consequently, the luminosity of this gas. Such variations of luminosity will be especially large with global instabilities in core; we will speak about it in the section concerning the star bursts.

Thus we see that the magnetic field of star produced due to ordered convection currents

- strips off the envelope from thermoconvective layer of core and compacts the core; this makes an additional thermoinsulating layer between the core and surrounding space that has minimal density and heat conduction;

- causes the mechanical rotation momentum, breaks the protostar off the mother cloud and gives it spherical shape;

- produces low-frequency oscillations in the core and envelope.

This all as the whole provides to the system the utmost stability and observed regular properties.