SELF

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O.N. Karavashkina and S.B. Karavashkin

This means, after conventional idea, reactions of synthesis do not go further than to be producing an iron - since the calculation shows heavier nuclei unstable [27, p. 102 and 237].

Fig. 2.45. Evolutionary tracks for stars having different masses. In brackets the stages of evolution are given; they correspond to the following points of diagram: (1- 2) - hydrogen burning in the convective nucleus, the duration of this process is thought to be 6,4410⁷ years; (2- 3) - general contraction of star, 2,210⁶ years; (3- 4) - hydrogen begins its burning in the layered source, 1,410⁵ years; (4- 5) - hydrogen burning in the thick layer, 1,210⁶ years; (5- 6) - expansion of convective envelope,  810⁵  years; (6- 7) - red giant stage, 510⁵  years; (7- 8) - helium burning in the nucleus, 610⁶  years; (8- 9) - convective envelope disappearing, 10⁶  years; (9- 10) - helium burning in the nucleus, 910⁶ years; (10- 11) - secondary expansion of convective envelope, 10⁶  years; (11- 12) - the nucleus contraction as helium burns out; (12- 13- 14) - layered helium source; (14- ?) - neutrino losses, red supergiant [1, p. 173, Fig. 51]

Shklovsky describes the thermonuclear evolution of star on the whole as follows: "The nucleus temperature growth is achieved by way of contraction of the star as the whole. By this reason, the tracks of evolution abruptly turn leftwards (see Fig. 2.45), i.e., the temperature of stellar surface grows. Very soon, however, star contraction stops, as all hydrogen has been burned out. Instead, there is 'switched on' a new region of nuclear reactions - thin envelope around already 'dead' (though very hot) nucleus. In further evolution of star, this envelope farther and farther leaves the centre of star, in this way increasing the mass of 'burned out' helium nucleus. At the same time there will occur the contraction of this nucleus and its heating. But with it, outer layers of such star begin fast and strongly 'inflating'. This means, with insignificantly varying flux, the surface temperature considerably lessen. Its evolutionary track abruptly turns rightwards and the star gains all properties of red supergiant. … The heat of nucleus can gain very high temperatures, about hundreds million Kelvins. At such temperatures, there 'switches on' the triple helium reaction. … The energy liberated in this reaction stops the nucleus further contracting. After this, the nucleus will slightly expand, and the radius of star will lessen" [1, p. 170].

As we see, in such version of evolution, the star as if tosses inside itself in mutually contradictive processes. As the next stage, after Shklovsky, "After exothermic reactions have been finished, the central parts of star contract again. When, due to contraction, the temperature there achieves 8 billion degrees, there occurs a nuclear reaction of special kind connected with heat absorption (endothermic). This reaction means the nuclei of ⁵⁶Fe decomposing to -particles and neutrons. It occurs very fast, the stellar nucleus abruptly cools. As the pressure in the star falls, it irrepressibly falls to the centre. This fall raises abrupt elevation of temperature in the star. So in the region close to the nucleus, where 'nuclear fuel' still has not 'burnt out', there start stormy thermonuclear reactions that mean the burst. The star envelope is thrown off, and as the result we are observing the II-type supernova" [11, p. 145].

Such collapse has been taken from the Hoyl and Fowler theory, which in this way explained the causes and mechanism of 'supernova'. In accordance with this theory, when an iron atom decomposed into four alpha-particles and four neutrons, there absorbs about 2,22 Mev per a nucleon of energy, or 2^.10¹⁸ erg/g [1, p. 270]. This would explain tremendous energy that is released in the explosion. True, this does not explain, why the same process of gravitational contraction and heating during long time controlled synthesis of substance - and suddenly caused the decomposition. The more, after Shklovsky whom we just cited, the iron nuclei decomposition, that in its essence makes the substance to be decompacting (i.e., the same substance needs now more volume), makes the substance falling to the centre. The collapse that as if takes place contradicts the physical meaning of process, it has not to raise further heating by orders but only to compensate the fall of pressure and temperature, - so here we also encounter the discrepancy. Further, after Shklovsky, the collapse of star causes the nucleus heating up to 20 and then to 40 billion degrees, which causes the rest of before-synthesised nuclei to decompose - this means new stages of collapse. This strange process of step-by-step collapse (which still no one observed in nature) would have to wipe out everything synthesised in the star before, and rather even the star itself. While after Gorbatsky [11, p. 145], this new stage of heating 'switches on' a new stage of thermonuclear synthesis. But with it, hydrogen and helium are again involved to the reaction - on one hand, they already have 'burnt out' before, and this did not cause explosive consequences, and on the other - they already have been exhausted in the 'boiler'.

Besides, after Narlikar, "there exist two ways to obtain nuclear energy. First, the nuclear energy is liberated in nuclear synthesis, when small nuclei merge into one larger, and this larger nucleus does not exceed the nuclei of iron group. … Second, the energy is liberated in fission of very heavy nuclei" [27, p. 237]. This means, up to some limit which is the iron, nuclei are synthesised with the energy release, and after this boundary the synthesis becomes energetically disadvantageous, the energy is liberated in the decomposition, and nuclei of heavy elements are not produced in the star [27, 237]. While we all know existent at least few dozens of stable elements heavier than iron.