СЕПАРАБЕЛИЗОВАННОЕ ВЗАИМОДЕЙСТВИЕ СКИРМА И

¨¸Ó³ ¢ —Ÿ. 2010. ’. 7, º 2(158). ‘. 193Ä199
”ˆ‡ˆŠ ‹…Œ…’›• —‘’ˆ– ˆ ’Œƒ Ÿ„. ’…ˆŸ
‘……‹ˆ‡‚… ‚‡ˆŒ„…‰‘’‚ˆ…
‘ŠˆŒ ˆ •Š’…ˆ‘’ˆŠˆ ƒˆƒ’‘Šƒ
„ˆ‹œƒ …‡‘
. . ·¸¥´Ó¥¢1 , A. . ‘¥¢¥·Ǫ̃´2
¡Ñ¥¤¨´¥´´Ò° ¨´¸É¨ÉÊÉ Ö¤¥·´ÒÌ ¨¸¸²¥¤μ¢ ´¨°, „Ê¡´ ˆ¸¸²¥¤μ¢ ´ Éμδμ¸ÉÓ ¨¸±²ÕÎ¥´¨Ö ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö ¢ · ¸¶·¥¤¥²¥´¨¨ ¸¨²Ò E1-¶¥·¥Ìμ¤μ¢ ¢
¶·¨¡²¨¦¥´¨¨ ¸²ÊÎ °´ÒÌ Ë § ¸ ¸¥¶ · ¡¥²¨§μ¢ ´´Ò³¨ ¸¨² ³¨ ‘±¨·³ .
Accuracy of the elimination of the spurious state from the E1-transition strength distribution is
studied within the random phase approximation with separabelized Skyrme forces.
PACS: 21.60.Jz, 24.30.Cz, 27.50.+e, 27.60.+j, 27.80.+w
‚‚…„…ˆ…
‚ ¶μ¸²¥¤´¨¥ £μ¤Ò ¶μÖ¢¨²¨¸Ó ´μ¢Ò¥ Ô±¸¶¥·¨³¥´É ²Ó´Ò¥ ¤ ´´Ò¥ [1Ä4] μ ¶¨£³¨-·¥§μ´ ´¸ Ì ¢ ´¥°É·μ´μ¨§¡ÒÉμδÒÌ Ö¤· Ì. ´¨ ¸É¨³Ê²¨·ÊÕÉ · §¢¨É¨¥ É¥μ·¥É¨Î¥¸±¨Ì ¨¸¸²¥¤μ¢ ´¨°. ¤´¨³ ¨§ μ¸´μ¢´ÒÌ ¶μ¤Ìμ¤μ¢ ¶·¨ 춨¸ ´¨¨ ¢¨¡· Í¨μ´´ÒÌ ¢μ§¡Ê¦¤¥´¨° Ö¢²Ö¥É¸Ö ¶·¨¡²¨¦¥´¨¥ ¸²ÊÎ °´ÒÌ Ë § (‘”). “봃 ´£ ·³μ´¨Î´μ¸É¨ ¢¨¡· Í¨μ´´ÒÌ ¸μ¸ÉμÖ´¨° ¢¥¤¥É ± ¶μÖ¢²¥´¨Õ ¸¢Ö§¨ ³¥¦¤Ê μ¤´μËμ´μ´´Ò³¨ ¨ ¡μ²¥¥ ¸²μ¦´Ò³¨ ±μ´Ë¨£Ê· ֳͨ¨. ˆ¸¶μ²Ó§μ¢ ´¨¥ ¶·μ¸ÉÒÌ ¸¥¶ · ¡¥²Ó´ÒÌ ¸¨² ¢ · ³± Ì ±¢ §¨Î ¸É¨Î´μ-Ëμ´μ´´μ°
³μ¤¥²¨ (Š”Œ) [5] ¶μ§¢μ²Ö¥É ʸ¶¥Ï´μ 춨¸Ò¢ ÉÓ ³´μ£¨¥ ¸¢μ°¸É¢ ¸É ¡¨²Ó´ÒÌ Ö¤¥·. ¤´ ±μ ¢ · ³± Ì Š”Œ ¨³¥ÕÉ¸Ö É·Ê¤´μ¸É¨ ¶·¨ ¨¸¸²¥¤μ¢ ´¨¨ Ö¤¥·, ʤ ²¥´´ÒÌ μÉ ²¨´¨¨
β-¸É ¡¨²Ó´μ¸É¨, ¨§-§ ´¥μ¡Ì줨³μ¸É¨ Ô±¸É· ¶μ²Öͨ¨ ¶ · ³¥É·μ¢ £ ³¨²ÓÉμ´¨ ´ ¢ ¶²μÌμ
¨§ÊÎ¥´´ÊÕ μ¡² ¸ÉÓ. μ ÔÉμ° ¶·¨Î¨´¥ ¡μ²¥¥ ¶·¥¤¶μÎɨɥ²Ó´Ò³¨ Ö¢²ÖÕÉ¸Ö ¸ ³μ¸μ£² ¸μ¢ ´´Ò¥ ³¨±·μ¸±μ¶¨Î¥¸±¨¥ ¶μ¤Ìμ¤Ò, ¨¸¶μ²Ó§ÊÕШ¥ ¤²Ö · ¸Î¥Éμ¢ ¸·¥¤´¥£μ ¶μ²Ö ¨ μ¸É Éμδμ£μ ¢§ ¨³μ¤¥°¸É¢¨Ö μ¤´¨ ¨ É¥ ¦¥ ÔËË¥±É¨¢´Ò¥ ´Ê±²μ´-´Ê±²μ´´Ò¥ ¸¨²Ò [6]. ‘²¥¤Ê¥É
μɳ¥É¨ÉÓ, ÎÉμ ¢ÒΨ¸²¥´¨Ö ¸ É ±¨³¨ ¸¨² ³¨ £·μ³μ§¤±¨, μ¸μ¡¥´´μ ¤²Ö Ö¤¥· ¸ ´¥§ ³±´ÊÉÒ³¨ μ¡μ²μα ³¨. ‚ Éμ ¦¥ ¢·¥³Ö ¢ÒΨ¸²¥´¨Ö ¸ ¶·μ¸ÉÒ³¨ ¸¥¶ · ¡¥²¨§μ¢ ´´Ò³¨ ¸¨² ³¨
Î ¸Éμ ¤ ÕÉ ¡²¨§±¨¥ ·¥§Ê²ÓÉ ÉÒ. ‚ · ¡μÉ Ì [7Ä10] μ¡Ñ¥¤¨´¥´Ò ¤μ¸Éμ¨´¸É¢ Š”Œ ¨ ¸ ³μ¸μ£² ¸μ¢ ´´ÒÌ ³μ¤¥²¥° ¸ ¸¨² ³¨ ‘±¨·³ . ‚ · ³± Ì É ±μ£μ ¶μ¤Ìμ¤ Ê¤ ²μ¸Ó 춨¸ ÉÓ
1 E-mail:
2 E-mail:
arsenev@theor.jinr.ru
sever@theor.jinr.ru
194 ·¸¥´Ó¥¢ . ., ‘¥¢¥·Ǫ̃´ A. .
¨ ¸¢μ°¸É¢ ´¨§±μ²¥¦ Ð¨Ì ¸μ¸ÉμÖ´¨°, ¨ Ì · ±É¥·¨¸É¨±¨ £¨£ ´É¸±¨Ì ³Ê²Óɨ¶μ²Ó´ÒÌ ·¥§μ´ ´¸μ¢ ¢ ¸Ë¥·¨Î¥¸±¨Ì Ö¤· Ì [7Ä12].
·¥¤¸É ¢²Ö¥É¸Ö ¶μ²¥§´Ò³ ¶·¨³¥´¨ÉÓ ÔÉμÉ ¶μ¤Ìμ¤ ± ¨¸¸²¥¤μ¢ ´¨Õ ¸¢μ°¸É¢ ¶¨£³¨·¥§μ´ ´¸μ¢. ¤´μ° ¨§ ¶·μ¡²¥³, ±μÉμ·ÊÕ ´¥μ¡Ì줨³μ ·¥Ï¨ÉÓ, Ö¢²Ö¥É¸Ö ¶·μ¡²¥³ ¨¸±²ÕÎ¥´¨Ö ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö, É ± ± ± μ´μ ³μ¦¥É ¸ÊÐ¥¸É¢¥´´μ ¨¸± §¨ÉÓ Ì · ±É¥·¨¸É¨±¨
¶¨£³¨-·¥§μ´ ´¸ . ‚ ´ ¸ÉμÖÐ¥° · ¡μÉ¥ ³Ò ´ ²¨§¨·Ê¥³ Éμδμ¸ÉÓ ¨¸±²ÕÎ¥´¨Ö ¤ÊÌμ¢μ£μ
¸μ¸ÉμÖ´¨Ö ¢ · ¸¶·¥¤¥²¥´¨¨ ¸¨²Ò E1-¶¥·¥Ìμ¤μ¢ ¢ μ¡² ¸É¨ ¶¨£³¨-·¥§μ´ ´¸μ¢ ± ± ¢ ¤¢ ¦¤Ò ³ £¨Î¥¸±¨Ì Ö¤· Ì, É ± ¨ ¢ Ö¤· Ì ¸ ´¥§ ³±´ÊÉÒ³¨ μ¡μ²μα ³¨. ¸Î¥ÉÒ ¢Ò¶μ²´¥´Ò
¢ μ¤´μËμ´μ´´μ³ ¶·¨¡²¨¦¥´¨¨. ‚ ± Î¥¸É¢¥ ¶·¨³¥· ¨¸¸²¥¤μ¢ ´Ò Ô´¥·£¨¨ ¨ ¢¥²¨Î¨´Ò
B(E1) ¤¨¶μ²Ó´ÒÌ ¸μ¸ÉμÖ´¨° ¢ 100,124,130,132 Sn ¨ 208 Pb.
1. Œ…’„
„¥É ²Ó´μ¥ ¨§²μ¦¥´¨¥ ´ Ï¥£μ ¶μ¤Ìμ¤ ³μ¦´μ ´ °É¨ ¢ · ¡μÉ Ì [7, 8, 10]. ‘·¥¤´¥¥
¶μ²¥ μ¶·¥¤¥²Ö¥É¸Ö ¶ÊÉ¥³ ·¥Ï¥´¨Ö Ê· ¢´¥´¨° • ·É·¨Ä”μ± (•”) ¸ ¸¨² ³¨ ‘±¨·³ . ‘¶ ·¨¢ ´¨¥ É· ±ÉÊ¥É¸Ö ¢ ¶·¨¡²¨¦¥´¨¨ ·¤¨´ Ċʶ¥· Ę·¨ËË¥· (Š˜). ¤´μÎ ¸É¨Î´Ò° ±μ´É¨´Êʳ ÊΨÉÒ¢ ¥É¸Ö ¶·¨ ¶μ³μШ ¤¨ £μ´ ²¨§ ͨ¨ £ ³¨²ÓÉμ´¨ ´ •” ´ ¡ §¨¸¥
¸μ¡¸É¢¥´´ÒÌ ËÊ´±Í¨° £ ·³μ´¨Î¥¸±μ£μ μ¸Í¨²²ÖÉμ· [13]. ¸É ÉμÎ´μ¥ ¢§ ¨³μ¤¥°¸É¢¨¥ ¢
Î ¸É¨Î´μ-¤Ò·μÎ´μ³ ± ´ ²¥ ¨ ± ´ ²¥ Î ¸É¨Í ÄÎ ¸É¨Í ³μ¦´μ ¶μ²ÊΨÉÓ ± ± ¢Éμ·Ò¥ ¶·μ¨§¢μ¤´Ò¥ ËÊ´±Í¨μ´ ² ¶²μÉ´μ¸É¨ Ô´¥·£¨¨ ¶μ ´μ·³ ²Ó´μ° ¨ ¶ ·´μ° ¶²μÉ´μ¸É¨ ´Ê±²μ´μ¢
¸μμÉ¢¥É¸É¢¥´´μ. ŒÒ ¶·¥¤¸É ¢²Ö¥³ Î ¸É¨Î´μ-¤Ò·μÎ´μ¥ ¢§ ¨³μ¤¥°¸É¢¨¥ ‘±¨·³ ¢ Ëμ·³¥
¸¨² ‹ ´¤ ÊÄŒ¨£¤ ² ¨ ¸μÌ· ´Ö¥³ Éμ²Ó±μ β¥´Ò ¸ l = 0. ‚Ò· ¦¥´¨Ö ¤²Ö F0 , G0 , F0 , G0
¶·¨¢¥¤¥´Ò ¢ · ¡μÉ¥ [14]. Œ É·¨Î´Ò¥ Ô²¥³¥´ÉÒ μ¸É Éμδμ£μ ¢§ ¨³μ¤¥°¸É¢¨Ö ³μ£ÊÉ ¡ÒÉÓ
§ ¶¨¸ ´Ò ¢ ¢¨¤¥ N ¸¥¶ · ¡¥²Ó´ÒÌ Î²¥´μ¢ [7, 8, 10].
ŒÒ · ¡μÉ ¥³ ¢ ‘”, μ¸´μ¢´μ¥ ¸μ¸ÉμÖ´¨¥ Ö¢²Ö¥É¸Ö Ëμ´μ´´Ò³ ¢ ±ÊÊ³μ³ |0. ‚μ§¡Ê¦¤¥´´Ò¥ μ¤´μËμ´μ´´Ò¥ ¸μ¸ÉμÖ´¨Ö £¥´¥·¨·ÊÕÉ¸Ö ¤¥°¸É¢¨¥³ 춥· Éμ· ·μ¦¤¥´¨Ö Ëμ´μ´μ¢ ´ ¢ ±Êʳ |i = Q+
λμi |0. „¨ £μ´ ²¨§μ¢ ¢ £ ³¨²ÓÉμ´¨ ´ ¢ ¶·μ¸É· ´¸É¢¥ μ¤´μËμ´μ´´ÒÌ ¸μ¸ÉμÖ´¨° |i, ³μ¦´μ ¶μ²ÊΨÉÓ ¸¨¸É¥³Ê ²¨´¥°´ÒÌ Ê· ¢´¥´¨°, ·¥Ï¨¢ ±μÉμ·ÊÕ
´ °¤¥³ §´ Î¥´¨Ö Ô´¥·£¨¨ ¨ Ëμ´μ´´Ò¥ ³¶²¨ÉÊ¤Ò ¢μ§¡Ê¦¤¥´´ÒÌ ¸μ¸ÉμÖ´¨°. ‘¥¶ · ¡¥²Ó´Ò° ¢¨¤ μ¸É Éμδμ£μ ¢§ ¨³μ¤¥°¸É¢¨Ö ¶μ§¢μ²Ö¥É ¸¢¥¸É¨ ¸¨¸É¥³Ê ²¨´¥°´ÒÌ Ê· ¢´¥´¨° ±
¸¥±Ê²Ö·´μ³Ê Ê· ¢´¥´¨Õ. ·¨ ÔÉμ³ ´¥μ¡Ì줨³μ ¢ÒΨ¸²¨ÉÓ μ¶·¥¤¥²¨É¥²Ó ³ É·¨ÍÒ, · §³¥·´μ¸ÉÓ ±μÉμ·μ° ´¥ § ¢¨¸¨É μÉ ±μ´Ë¨£Ê· Í¨μ´´μ£μ ¶·μ¸É· ´¸É¢ [7, 8, 10]. ɳ¥É¨³,
ÎÉμ ¢ Š”Œ [5, 15] ÔÉμ ¸¥±Ê²Ö·´μ¥ Ê· ¢´¥´¨¥ ¨³¥¥É É ±μ° ¦¥ ¢¨¤, ´μ ¢ ¶·¥¤¸É ¢²¥´´μ³
¶μ¤Ì줥 μ¤´μÎ ¸É¨Î´Ò° ¸¶¥±É· ¨ ¶ · ³¥É·Ò Î ¸É¨Î´μ-¤Ò·μδμ£μ ¢§ ¨³μ¤¥°¸É¢¨Ö · ¸¸Î¨ÉÒ¢ ÕÉ¸Ö ¸ ¸¨² ³¨ ‘±¨·³ . „²Ö Ê봃 ¸²μ¦´ÒÌ ±μ´Ë¨£Ê· ͨ° ¢μ²´μ¢Ò¥ ËÊ´±Í¨¨
¢μ§¡Ê¦¤¥´´ÒÌ ¸μ¸ÉμÖ´¨° § ¶¨¸Ò¢ ÕÉ¸Ö ¢ ¢¨¤¥ ¸Ê¶¥·¶μ§¨Í¨¨ β¥´μ¢ ¸ · §²¨Î´Ò³ Ψ¸²μ³
Ëμ´μ´´ÒÌ μ¶¥· Éμ·μ¢, ¨ ¸μμÉ¢¥É¸É¢ÊÕШ¥ Ê· ¢´¥´¨Ö ¶·¨¢¥¤¥´Ò ¢ · ¡μÉ¥ [9].
‚ ¸¨²Ê Éμ£μ, ÎÉμ ¸ ³μ¸μ£² ¸μ¢ ´¨¥ ¢ ´ Ï¥³ ¶μ¤Ì줥 ´ ·ÊÏ¥´μ ¨§-§ ¶·¨¡²¨¦¥´´μ£μ
Ê봃 ¸±μ·μ¸É´ÒÌ Î²¥´μ¢ Î ¸É¨Î´μ-¤Ò·μδμ£μ ¢§ ¨³μ¤¥°¸É¢¨Ö, ´¥μ¡Ì줨³μ ¨¸±²ÕΨÉÓ
¤ÊÌμ¢μ¥ ¸μ¸ÉμÖ´¨¥, μ¡Ê¸²μ¢²¥´´μ¥ ¤¢¨¦¥´¨¥³ Ö¤· ± ± Í¥²μ£μ. ·¨³¥¸Ó ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö ³μ¦¥É ¶·¨¸ÊÉ¸É¢μ¢ ÉÓ ± ± ±μ³¶μ´¥´É ¢ ± ¦¤μ° ¨§ ¢μ²´μ¢ÒÌ ËÊ´±Í¨° ¢μ§¡Ê¦¤¥´´ÒÌ
¸μ¸ÉμÖ´¨°. ‚ ¶·¥¤¸É ¢²¥´´μ³ ¶μ¤Ì줥 [8, 11] ¤²Ö ¨§ÊÎ¥´¨Ö ¸¢μ°¸É¢ £¨£ ´É¸±¨Ì ¤¨¶μ²Ó´ÒÌ ·¥§μ´ ´¸μ¢ (ƒ„) ¡Ò² ¶·¨³¥´¥´ Ìμ·μÏμ ¨§¢¥¸É´Ò° ³¥Éμ¤ ¢μ¸¸É ´μ¢²¥´¨Ö É· ´¸²ÖÍ¨μ´´μ° ¨´¢ ·¨ ´É´μ¸É¨, ±μÉμ·Ò° § ±²ÕÎ ¥É¸Ö ¢ ¢¢¥¤¥´¨¨ ÔËË¥±É¨¢´ÒÌ ´¥°É·μ´´μ£μ
Z
N
eneff = − e ¨ ¶·μÉμ´´μ£μ epeff = e § ·Ö¤μ¢ [16]. ·¨¢¥¤¥´´ Ö ¢¥·μÖÉ´μ¸ÉÓ Ô²¥±É·¨Î¥A
A
‘¥¶ · ¡¥²¨§μ¢ ´´μ¥ ¢§ ¨³μ¤¥°¸É¢¨¥ ‘±¨·³ 195
¸±μ£μ ¤¨¶μ²Ó´μ£μ ¶¥·¥Ìμ¤ ¨³¥¥É ¢¨¤
2
n
p
−
n
p
→
1
)
=
i
|
M̂
|
0
+
e
i
|
M̂
|
0
B(E1; 0+
e
,
gs
eff
i
eff
£¤¥ M̂ n =
N
i
ri Y1μ (r̂i ), M̂ p =
Z
(1)
ri Y1μ (r̂i ).
i
·¨³¥´¨³ ²¨ ÔÉμÉ ³¥Éμ¤ ¤²Ö ¨¸¸²¥¤μ¢ ´¨Ö ´¨§±μÔ´¥·£¥É¨Î¥¸±μ° μ¡² ¸É¨ · ¸¶·¥¤¥²¥´¨Ö ¸¨²Ò E1-¶¥·¥Ìμ¤μ¢? É¢¥ÉÊ ´ ÔÉμÉ ¢μ¶·μ¸ ¨ ¶μ¸¢ÖÐ¥´ ¤ ´´ Ö · ¡μÉ . ŒÒ ¢μ¸¶μ²Ó§Ê¥³¸Ö ¶·μÍ¥¤Ê·μ° μ·Éμ£μ´ ²¨§ ͨ¨ ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö ¢¸¥³ ˨§¨Î¥¸±¨³ ¸μ¸ÉμÖ´¨Ö³ [17, 18]. ‚μ²´μ¢ÊÕ ËÊ´±Í¨Õ ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö, μÉ¢¥Î ÕÐ¥£μ ¤¢¨¦¥´¨Õ Í¥´É· ³ ¸¸, ¶·¥¤¸É ¢¨³ ¢ ¢¨¤¥
| s = ŝ | 0,
(2)
£¤¥ ŝ = M̂ p + M̂ n . Œμ¦´μ ¶μ¸É·μ¨ÉÓ ¡ §¨¸, ±μÉμ·Ò° μ·Éμ£μ´ ²¥´ ¤ÊÌμ¢μ³Ê ¸μ¸ÉμÖ´¨Õ:
| ı̃ = Ni (| i − αi | s) ,
(3)
£¤¥ Ni Å ´μ·³¨·μ¢μδҰ ±μÔË˨ͨ¥´É, αi ´ Ì줨³ ¨§ ʸ²μ¢¨Ö
ı̃ | s = 0.
(4)
‹¥£±μ ¶μ± § ÉÓ, ÎÉμ ¶·¨¢¥¤¥´´ Ö ¢¥·μÖÉ´μ¸ÉÓ ¶¥·¥Ìμ¤ ³¥¦¤Ê μ¸´μ¢´Ò³ ¨ ¢μ§¡Ê¦¤¥´´Ò³
¸μ¸ÉμÖ´¨Ö³¨ | ı̃ · ¢´ 2
−
p
i |M̂ | 0 ,
B(E1; 0+
→
1
)
=
Z
(5)
e
gs
i
ii
i
Zii = Ni
δii
s | i i | s
−
s | s
.
(6)
2. …‡“‹œ’’› ‘—…’‚
‚ ± Î¥¸É¢¥ ¶·¨³¥· · ¸¸³μÉ·¨³ · ¸¶·¥¤¥²¥´¨¥ ¶·¨¢¥¤¥´´ÒÌ ¢¥·μÖÉ´μ¸É¥° E1-¶¥·¥Ìμ¤μ¢ ¢ 100,124,130,132 Sn ¨ 208 Pb. ‚ · ¸Î¥É Ì ¨¸¶μ²Ó§μ¢ ² ¸Ó ¶ · ³¥É·¨§ ꬅ ¸¨² ‘±¨·³ SLy4 [19]. ¤´¨³ ¨§ ʸ²μ¢¨° ¶·¨ ¢Ò¡μ·¥ ¶ · ³¥É·μ¢ SLy4 ¡Ò²μ 춨¸ ´¨¥ ¸¢μ°¸É¢ ´¥°É·μ´´μ° ³ É¥·¨¨, ¶μÔÉμ³Ê ÔÉ ¶ · ³¥É·¨§ Í¨Ö É ± ¶μ¶Ê²Ö·´ ¤²Ö 춨¸ ´¨Ö ¸¢μ°¸É¢ Ö¤¥· ¸
¨§¡ÒÉ±μ³ ´¥°É·μ´μ¢. ·´Ò¥ ±μ··¥²Öͨ¨ ÊΨÉÒ¢ ²¨¸Ó ¢ ¶·¨¡²¨¦¥´¨¨ Š˜. · ³¥É·Ò
±μ´¸É ´É´μ£μ ¸¶ ·¨¢ É¥²Ó´μ£μ ¢§ ¨³μ¤¥°¸É¢¨Ö ˨±¸¨·μ¢ ²¨¸Ó É ±, ÎÉμ¡Ò ¢μ¸¶·μ¨§¢¥¸É¨
Ô±¸¶¥·¨³¥´É ²Ó´Ò¥ §´ Î¥´¨Ö · §´μ¸É¨ ³ ¸¸ ¸μ¸¥¤´¨Ì Ö¤¥· [20]. ŒÒ ¶·¥´¥¡·¥£²¨ μ¸É Éμδҳ ¢§ ¨³μ¤¥°¸É¢¨¥³ ¢ ± ´ ²¥ Î ¸É¨Í ÄÎ ¸É¨Í , É ± ± ± ¥£μ ¢²¨Ö´¨¥ ´ · ¸¶·¥¤¥²¥´¨¥
¸¨²Ò E1-¶¥·¥Ìμ¤μ¢ ³ ²μ.
δ¥³ μ¡¸Ê¦¤¥´¨¥ ¸ 208 Pb. E1-¸¨²μ¢ Ö ËÊ´±Í¨Ö ¶μ± § ´ ´ ·¨¸. 1,
−
b(E1; ω) =
B(E1; 0+
(7)
gs → 1i )ρ(ω − E1− ).
i
i
196 ·¸¥´Ó¥¢ . ., ‘¥¢¥·Ǫ̃´ A. .
·¨ ʸ·¥¤´¥´¨¨ ¡· ² ¸Ó ²μ·¥´Í¥¢¸± Ö ËÊ´±Í¨Ö ¸ ¶ · ³¥É·μ³ · §³ §±¨ Δ = 1 ŒÔ‚ [5].
¸¸Î¨É ´´Ò¥ Ô´¥·£¨¨ Í¥´É·μ¨¤μ¢ ƒ„
−
E1− B(E1; 0+
gs → 1i )
i
Ec = i −
B(E1; 0+
gs → 1i )
(8)
i
¨ Ô±¸¶¥·¨³¥´É ²Ó´Ò¥ ¤ ´´Ò¥ [2, 21] ¶·¨¢¥¤¥´Ò ¢ É ¡²¨Í¥. ¥§Ê²ÓÉ ÉÒ · ¸Î¥Éμ¢ ¸ ÊÎ¥Éμ³
μ·Éμ£μ´ ²¨§ ͨ¨ (3) ¶μ± § ´Ò ¸¶²μÏ´Ò³¨ ²¨´¨Ö³¨ ´ ·¨¸Ê´± Ì (±μ²μ´± I ¢ É ¡²¨Í¥),
· ¸Î¥Éμ¢ ¸ ÔËË¥±É¨¢´Ò³¨ § ·Ö¤ ³¨ (1) Å ¶Ê´±É¨·´Ò³¨ ²¨´¨Ö³¨ (±μ²μ´± II ¢ É ¡²¨Í¥).
˜É·¨Ìμ¢Ò¥ ²¨´¨¨ (±μ²μ´± III ¢ É ¡²¨Í¥) ¸μμÉ¢¥É¸É¢ÊÕÉ · ¸Î¥É ³ ¶μ Ëμ·³Ê²¥
2
−
p
|
M̂
B(E1; 0+
→
1
)
=
|
0
ei
,
gs
i
(9)
±μ£¤ ¤ÊÌμ¢μ¥ ¸μ¸ÉμÖ´¨¥ ´¥ ¨¸±²ÕÎ¥´μ. Š ± ¢¨¤´μ ¨§ ·¨¸. 1, ¢μ¸¸É ´μ¢²¥´¨¥ É· ´¸²ÖÍ¨μ´´μ° ¨´¢ ·¨ ´É´μ¸É¨ ¶·¨¢μ¤¨É ± § ³¥É´μ³Ê ¶¥·¥· ¸¶·¥¤¥²¥´¨Õ ¤¨¶μ²Ó´μ° ¸¨²Ò. Éμ
¸± §Ò¢ ¥É¸Ö ¤ ¦¥ ´ ¨´É¥£· ²Ó´ÒÌ Ì · ±É¥·¨¸É¨± Ì (¸³. É ¡²¨ÍÊ). ˆ§ ·¨¸. 1 ³μ¦´μ § ±²ÕΨÉÓ, ÎÉμ ·¥§Ê²ÓÉ ÉÒ · ¸Î¥Éμ¢ ¸ ÔËË¥±É¨¢´Ò³¨ § ·Ö¤ ³¨ μÎ¥´Ó ¡²¨§±¨ ± ·¥§Ê²ÓÉ É ³,
¶μ²ÊÎ¥´´Ò³ ¸ ÊÎ¥Éμ³ μ·Éμ£μ´ ²¨§ ͨ¨ (3). ‚¨¤´μ, ÎÉμ ±μ··¥±É´Ò° Ê봃 ¤¢¨¦¥´¨Ö Í¥´É· ³ ¸¸ ¸ÊÐ¥¸É¢¥´ ¤²Ö ¶· ¢¨²Ó´μ£μ 춨¸ ´¨Ö ´¨§±μÔ´¥·£¥É¨Î¥¸±μ° μ¡² ¸É¨. ‚ ¨´É¥·¢ ²¥
Ô´¥·£¨°
μ·Éμ£μ´ ²¨§ ͨ¨ (3) (¸ ÔËË¥±É¨¢´Ò³¨
§ ·Ö¤ ³¨)
¤μ 9 ŒÔ‚ ´ Ï2· ¸Î¥É2 ¸ ÊÎ¥Éμ³
B(E1) =
¤ ¥É
B(E1) =2,2 e · ˳ (1,9 e2 · ˳2 ), · ¸Î¥É ¶μ Ëμ·³Ê²¥ (9) Å
0,4 e2 · ˳2 . ɳ¥É¨³, ÎÉμ ¢ · ³± Ì Š”Œ ʤ ¥É¸Ö 춨¸ ÉÓ Ì · ±É¥·¨¸É¨±¨ ƒ„ ¨ ¸¢μ°¸É¢ ¶¨£³¨-·¥§μ´ ´¸ ¢ 208 Pb ¸ ÊÎ¥Éμ³ ¢²¨Ö´¨Ö ¤¢ÊÌ- ¨ É·¥ÌËμ´μ´´ÒÌ ±μ´Ë¨£Ê· ͨ° [22].
¨¸. 1. E1-¸¨²μ¢ Ö ËÊ´±Í¨Ö ¤²Ö 208 Pb. ‘¶²μÏ´ Ö ²¨´¨Ö Å · ¸Î¥É, ÊΨÉÒ¢ ÕШ° μ·Éμ£μ´ ²¨§ Í¨Õ ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö ¢¸¥³ ˨§¨Î¥¸±¨³ ¸μ¸ÉμÖ´¨Ö³; ÏÉ·¨Ìμ¢ Ö Å · ¸Î¥É ¡¥§ μ·Éμ£μ´ ²¨§ ͨ¨;
¶Ê´±É¨·´ Ö Å · ¸Î¥É ¸ ÔËË¥±É¨¢´Ò³¨ § ·Ö¤ ³¨.
‚¥¸μ¢ Ö ËÊ´±Í¨Ö Å ²μ·¥´Í¥¢¸± Ö ËÊ´±Í¨Ö ¸ ¶ · ³¥É·μ³ ʸ·¥¤´¥´¨Ö Δ = 1 ŒÔ‚
¨¸. 2. ’μ ¦¥, ÎÉμ ¨ ´ ·¨¸. 1, ¤²Ö
132
Sn
‘¥¶ · ¡¥²¨§μ¢ ´´μ¥ ¢§ ¨³μ¤¥°¸É¢¨¥ ‘±¨·³ 197
‡´ Î¥´¨Ö Ô´¥·£¨¨ ƒ„ (¸³. ¶μ¤·μ¡´μ¸É¨ ¢ É¥±¸É¥)
Ec , ŒÔ‚
Ÿ¤·μ
100
Sn
Sn
130
Sn
132
Sn
208
Pb
124
I
’¥μ·¨Ö
II
III
17,5
17,0
16,5
16,0
14,3
17,5
16,9
16,4
16,0
14,3
17,2
16,7
16,0
15,7
14,0
±¸¶¥·¨³¥´É
15,2
15,9
16,1
13,4
¡¸Ê¤¨³ · ¸¶·¥¤¥²¥´¨¥ ¸¨²Ò ¤¨¶μ²Ó´ÒÌ ¢μ§¡Ê¦¤¥´¨° ¢ ´¥°É·μ´μ¨§¡ÒÉμÎ´μ³ Ö¤·¥
Sn. ‘¢μ°¸É¢ ¤¨¶μ²Ó´ÒÌ ¢μ§¡Ê¦¤¥´¨° ¢ 132 Sn ¨´É¥´¸¨¢´μ ¨§ÊÎ ²¨¸Ó ± ± Ô±¸¶¥·¨³¥´É ²Ó´μ [2, 3], É ± ¨ É¥μ·¥É¨Î¥¸±¨ [12, 23Ä25]. ˆ§ É ¡²¨ÍÒ ¢¨¤´μ, ÎÉμ ´ Ï · ¸Î¥É Ô´¥·£¨¨
ƒ„ ¸μ£² ¸Ê¥É¸Ö ¸ Ô±¸¶¥·¨³¥´É ²Ó´Ò³¨ ¤ ´´Ò³¨ [2]. ±¸¶¥·¨³¥´É ²Ó´μ ¶¨£³¨-·¥§μ´ ´¸
μ¡´ ·Ê¦¥´ ¶·¨ Ô´¥·£¨¨ 9,8 ŒÔ‚ [2], ÎÉμ ¡²¨§±μ ± ·¥§Ê²ÓÉ É ³ ´ Ï¨Ì · ¸Î¥Éμ¢ (·¨¸. 2).
¨¸. 2 ´ £²Ö¤´μ ¤¥³μ´¸É·¨·Ê¥É, ÎÉμ ¢ · ¸Î¥É Ì ‘” ¸ ´ ·ÊÏ¥´´μ° É· ´¸²ÖÍ¨μ´´μ° ¨´¢ ·¨ ´É´μ¸ÉÓÕ ¤ÊÌμ¢μ¥ ¸μ¸ÉμÖ´¨¥ ¶·¨¸ÊÉ¸É¢Ê¥É ¢ ¢μ²´μ¢ÒÌ ËÊ´±Í¨ÖÌ ¢μ§¡Ê¦¤¥´´ÒÌ ¸μ¸ÉμÖ´¨°, ¨ ¢¢¥¤¥´¨¥ ÔËË¥±É¨¢´ÒÌ § ·Ö¤μ¢ ¶μ§¢μ²Ö¥É ¨¸±²ÕΨÉÓ ¤ÊÌμ¢μ¥ ¸μ¸ÉμÖ´¨¥ ¢ μ¡² ¸É¨
´¨§±¨Ì Ô´¥·£¨°. μ¤É¢¥·¦¤ ÕÉ ÔÉμÉ ¢Ò¢μ¤ ¨ ¨´É¥£· ²Ó´Ò¥
Ì · ±É¥·¨¸É¨±¨. ‚ ¨´É¥·¢ ²¥
Ô´¥·£¨° ¤μ 11 ŒÔ‚ ¨´É¥£· ²Ó´ Ö ¤¨¶μ²Ó´ Ö ¸¨² ( B(E1)) · ¢´ 0,3 e2 · ˳2 , ¥¸²¨ ´¥
ʤ ²¥´ ¶·¨³¥¸Ó ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö. ¸Î¥ÉÒ ¸ ÊÎ¥Éμ³ μ·Éμ£μ´ ²¨§ ͨ¨ (3), ¸ ÔËË¥±É¨¢´Ò³¨ § ·Ö¤ ³¨ ¤ ÕÉ ¨´É¥£· ²Ó´ÊÕ ¤¨¶μ²Ó´ÊÕ ¸¨²Ê 1,5 ¨ 1,2 e2 · ˳2 ¸μμÉ¢¥É¸É¢¥´´μ.
132
¨¸. 3. ’μ ¦¥, ÎÉμ ¨ ´ ·¨¸. 1, ¤²Ö
130
Sn
¨¸. 4. ’μ ¦¥, ÎÉμ ¨ ´ ·¨¸. 1, ¤²Ö
124
Sn
Š É ±μ³Ê ¦¥ ¢Ò¢μ¤Ê ³μ¦´μ ¶·¨°É¨ ¶·¨ ¨§ÊÎ¥´¨¨ Ö¤¥·, ʤ ²¥´´ÒÌ μÉ § ¶μ²´¥´´ÒÌ
μ¡μ²μÎ¥±. ·¨¸. 3 ¨ 4 ¶·¨¢¥¤¥´Ò E1-¸¨²μ¢Ò¥ ËÊ´±Í¨¨ ¤²Ö 130 Sn ¨ 124 Sn ¸μμÉ¢¥É¸É¢¥´´μ. ɳ¥É¨³, ÎÉμ ¤²Ö 130 Sn ¨¸±²ÕÎ¥´¨¥ ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö ¶·¨¢μ¤¨É ± ¶μÖ¢²¥´¨Õ
¶μ¤¸É·Ê±ÉÊ· ¢ · °μ´¥ 9,6 ŒÔ‚. ±¸¶¥·¨³¥´É ¤ ¥É §´ Î¥´¨¥ Ô´¥·£¨¨ ¶¨£³¨-·¥§μ´ ´¸ ¢
130
Sn 10,1 ŒÔ‚ [2]. ¸¸³μÉ·¨³ E1-¸¨²μ¢ÊÕ ËÊ´±Í¨Õ ¤²Ö ¶·μÉμ´μ¨§¡ÒÉμδμ£μ Ö¤· 198 ·¸¥´Ó¥¢ . ., ‘¥¢¥·Ǫ̃´ A. .
¨¸. 5. ’μ ¦¥, ÎÉμ ¨ ´ ·¨¸. 1, ¤²Ö
100
Sn
100
Sn (·¨¸. 5). …¸²¨ ´¥ ¨¸±²ÕÎ ÉÓ ¢²¨Ö´¨¥ ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö, ¸¨²μ¢ Ö ËÊ´±Í¨Ö ¡Ê¤¥É
¨³¥ÉÓ Ö·±¨° ¶¨± ¢ ´¨§±μÔ´¥·£¥É¨Î¥¸±μ³ Ì¢μ¸É¥ ƒ„ ¶·¨ Ô´¥·£¨¨ 12,5 ŒÔ‚. Šμ··¥±É´Ò°
Ê봃 ¤¢¨¦¥´¨Ö Í¥´É· ³ ¸¸ § ³¥É´μ ʳ¥´ÓÏ ¥É ÔÉμÉ ¶¨±. ’ ±¨³ μ¡· §μ³, ¨¸±²ÕÎ¥´¨¥
¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö ¢ ¦´μ É ±¦¥ ¤²Ö ¶·μÉμ´μ¨§¡ÒÉμδÒÌ Ö¤¥·.
‡Š‹—…ˆ…
‚ · ³± Ì ¶·¨¡²¨¦¥´¨Ö ¸²ÊÎ °´ÒÌ Ë § ¸ ¸¥¶ · ¡¥²¨§μ¢ ´´Ò³¨ ¸¨² ³¨ ‘±¨·³ ¨¸¸²¥¤μ¢ ´Ò · ¸¶·¥¤¥²¥´¨Ö ¸¨²Ò E1-¶¥·¥Ìμ¤μ¢ ¤²Ö 100,124,130,132 Sn ¨ 208 Pb. ¸¸Î¨É ´´Ò¥
Ô´¥·£¨¨ ƒ„ Ìμ·μÏμ ¸μ£² ¸ÊÕÉ¸Ö ¸ ¨³¥ÕШ³¨¸Ö Ô±¸¶¥·¨³¥´É ²Ó´Ò³¨ ¤ ´´Ò³¨. Œ¥Éμ¤
¨¸±²ÕÎ¥´¨Ö ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö ¸ ¶μ³μÐÓÕ ¢¢¥¤¥´¨Ö ÔËË¥±É¨¢´ÒÌ § ·Ö¤μ¢ ¨ μ·Éμ£μ´ ²¨§ ꬅ ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö ¢¸¥³ ˨§¨Î¥¸±¨³ ¸μ¸ÉμÖ´¨Ö³ ¤ ¥É μÎ¥´Ó ¡²¨§±¨¥ ·¥§Ê²ÓÉ ÉÒ.
ˆ¸±²ÕÎ¥´¨¥ ¤ÊÌμ¢μ£μ ¸μ¸ÉμÖ´¨Ö ¢ ¦´μ ¤²Ö 춨¸ ´¨Ö ¤¨¶μ²Ó´ÒÌ ¢μ§¡Ê¦¤¥´¨° ¢ ´¨§±μÔ´¥·£¥É¨Î¥¸±μ° μ¡² ¸É¨. ‚ ´ ¸ÉμÖÐ¥¥ ¢·¥³Ö ¨¸¸²¥¤Ê¥É¸Ö ¢²¨Ö´¨¥ ±μ³¶μ´¥´É ¤ÊÌμ¢μ£μ
¸μ¸ÉμÖ´¨Ö ´ ´£ ·³μ´¨Î¥¸±¨¥ ÔËË¥±ÉÒ.
¢Éμ·Ò ¢Ò· ¦ ÕÉ £²Ê¡μ±ÊÕ ¡² £μ¤ ·´μ¸ÉÓ ¶·μË¥¸¸μ·Ê ‚. ‚. ‚μ·μ´μ¢Ê § ¶μ²¥§´Ò¥
μ¡¸Ê¦¤¥´¨Ö.
‘ˆ‘Š ‹ˆ’…’“›
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μ²ÊÎ¥´μ 25 ³ ·É 2009 £.