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Qator 880: Yadrosi 10 million kelvingacha qizigan Quyoshda vodorod geliyga [[proton-proton sikli]] deb ataladigan reaksiyda aylanadi:<ref name="synthesis">{{cite journal \| display-authors=1 \| last1=Wallerstein \| first1=G. \| last2=Iben Jr. \| first2=I. \| last3=Parker \| first3=P. \| last4=Boesgaard \| first4=A. M. \| last5=Hale \| first5=G. M. \| last6=Champagne \| first6=A. E. \| last7=Barnes \| first7=C. A. \| last8=KM-dppeler \| first8=F. \| last9=Smith \| first9=V. V. \| last10=Hoffman \| first10=R. D. \| last11=Timmes \| first11=F. X. \| last12=Sneden \| first12=C. \| last13=Boyd \| first13=R. N. \| last14=Meyer \| first14=B. S. \| last15=Lambert \| first15=D. L. \| title=Synthesis of the elements in stars: forty years of progress \| journal=Reviews of Modern Physics \| year=1999 \| volume=69 \| issue=4 \| pages=995–1084 \| url=http://authors.library.caltech.edu/10255/1/WALrmp97.pdf\| format=PDF \| accessdate=2006-08-04 \| doi=10.1103/RevModPhys.69.995 \| bibcode=1997RvMP...69..995W}}</ref> :4[[Vodorod-1\|<sup>1</sup>H]] → 2[[deyteriy\|<sup>2</sup>H]] + 2[[pozitron\|e<sup>+</sup>]] + 2[[neytrino\|ν<sub>e</sub>]] (4.,0 M[[elektronvolt\|eV]] + 1.0 MeV) :2<sup>1</sup>H + 2<sup>2</sup>H → 2[[Geliy-3\|<sup>3</sup>He]] + 2[[foton\|γ]] (5.,5 MeV) :2<sup>3</sup>He → [[Geliy-4\|<sup>4</sup>He]] + 2<sup>1</sup>H (12.,9 MeV) Bu reaksiyalar quyidagi reaksiyaga olib keladi: :4<sup>1</sup>H → <sup>4</sup>He + 2e<sup>+</sup> + 2γ + 2ν<sub>e</sub> (26.,7 MeV) bu yerda e<sup>+</sup> — [[pozitron]], γ — gamma nurlanish fotoni, ν<sub>e</sub> — [[neytrino]], H va He — mos ravishda vodorod va geliy izotoplari. Bu reaksiya natijasida millionlab elektron volt energiya chiqadi (eV juda kichik energiya miqdori, shuning uchun bu energiya katta emas). Biroq bir vaqtda bunday reaksiyalarning juda ulkan miqdori sodir boʻlgani uchun yulduz nurlanishi kuchli boʻladi. Qator 911: Massivroq yulduzlarda geliy [[kataliz\|katalizatori]] uglerod boʻlgan [[CNO-sikl\|uglerod-azot-kislorod siklida]] ajralib chiqadi.<ref name="synthesis" /> Massasi 0,5 va 10 Quyosh massasi oraligʻida, yadrosi 100 million kelvinda boʻlgan evolutsiyalangan yulduzlarda geliy [[berilliy]] ishtirokidagi [[uchlamchi alfa jarayoni]]da uglerodga aylanishi mumkin:<ref name="synthesis" /> In evolved stars with cores at 100 million kelvin and masses between 0.5 and 10 solar masses, helium can be transformed into carbon in the [[triple-alpha process]] that uses the intermediate element [[beryllium]]:<ref name="synthesis" /> :<sup>4</sup>He + <sup>4</sup>He + 92 keV → [[~~Isotopes of beryllium~~Berilliy\|<sup>8</sup>Be]] :<sup>4</sup>He + <sup>8</sup>Be + 67 keV → <sup>12</sup>C :<sup>12</sup>C → [[~~Carbon~~Uglerod-12\|<sup>12</sup>C]] + γ + 7.,4 MeV Natijaviy reaksiya quyidagicha: ~~For an overall reaction of:~~ :3<sup>4</sup>He → <sup>12</sup>C + γ + 7.,2 MeV In massive stars, heavier elements can also be burned in a contracting core through the [[neon burning process]] and [[oxygen burning process]]. The final stage in the stellar nucleosynthesis process is the [[silicon burning process]] that results in the production of the stable isotope iron-56. Fusion can not proceed any further except through an [[endothermic]] process, and so further energy can only be produced through gravitational collapse.<ref name="synthesis" />

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