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Magicheskie yadra

- atomnye yadra, soderzhashie t.n. magicheskoe chislo (2, 8, 20, 28, 50, 82, 126) protonov (r) ili neitronov (p). Takimi yadrami yavl., napr.: $_2^4$Ne(2p, 2n), $_8^{16}$0(8r, 8n), $_{20}^{40}$Ca (20p, 20n), $_{32}^{60}$Ni (28p), $_{50}^{88}$Cr (50n), $_{70}^{120}$Sn (50p), $_{82}^{138}$Ba (82n), $_{126}^{208}$Pb (82r, 126n). V atomnom yadre neitrony i protony mogut obrazovyvat' zapolnennye obolochki (sm. Urovni energii), analogichnye elektronnym obolochkam inertnyh gazov. Magich. chisla sootvetstvuyut chislam protonov ili neitronov, zapolnyayushih eti obolochki. Sredi M. ya. naibolee vydelyayutsya yadra, u k-ryh zapolneny kak protonnye, tak i neitronnye obolochki (4He, 16O, 40Sa, 208R'). Takie yadra naz. dvazhdy magicheskimi. M. ya., i osobenno dvazhdy magicheskie, obladayut povyshennoi ustoichivost'yu, maloi veroyatnost'yu $\alpha$-raspada, maloi effektivnost'yu neitronnogo zahvata. M. ya. bolee rasprostraneny vo Vselennoi po sravneniyu s yadrami, soderzhashimi drugoe blizkoe chislo nuklonov (sm. Rasprostranennost' elementov).

(D.A. Frank-Kameneckii)


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Publikacii s klyuchevymi slovami: magicheskie yadra - magicheskie chisla - atomnoe yadro
Publikacii so slovami: magicheskie yadra - magicheskie chisla - atomnoe yadro
Karta smyslovyh svyazei dlya termina MAGIChESKIE YaDRA
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