|
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.: Ne(2p, 2n), 0(8r, 8n), Ca (20p, 20n), Ni (28p), Cr (50n), Sn (50p), Ba (82n), 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 -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)
D. A. Frank-Kameneckii, "Fizika Kosmosa", 1986
Glossarii Astronet.ru
L | R | A | B | V | G | D | E | Zh | Z | I | ' | K | L | M | N | O | P | R | S | T | U | F | H | C | Ch | Sh | Sh | E | Yu | Ya
Publikacii s klyuchevymi slovami:
magicheskie yadra - magicheskie chisla - atomnoe yadro
Publikacii so slovami: magicheskie yadra - magicheskie chisla - atomnoe yadro | |
Sm. takzhe:
|