Thursday, January 12, 2017

nuclear physics - Why some nuclei with "magic" numbers of neutrons have a half-life less than their neighbor isotopes?


It's easy to find the "magic" numbers of neutrons on the diagrams of alpha-decay energy: 82, 126, 152, 162. Such "magic" nuclei should be more stable than their neighbors.




But why some nuclei with "magic" numbers of neutrons have a half-life less than their neighbor isotopes with odd numbers of neutrons?


Examples for "magic" number 126:


A half-life of "magic" Po-210 is 138 days, whereas a half-life of neighbor isotope Po-209 is 102 years.


A half-life of "magic" Ra-214 is 2.46 sec, whereas a half-life of neighbor isotope Ra-213 is 2.74 min.


Examples for "magic" number 152:


A half-life of "magic" Cm-248 is 348 thousand years, whereas a half-life of neighbor isotope Cm-247 is 16 million years!


A half-life of "magic" Cf-250 is 13 years, whereas a half-life of neighbor isotope Cf-249 is 351 years.


P.S. Source of the diagrams data




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