Isotopes of Neptunium (Z=93)

Click on an isotope to get more information about its decay
Isotope Half-life Spin Parity Decay Mode(s) or Abundance
225Np 6 ms %A=?
226Np 35 ms %A=100
227Np 0.51 s %A=100, %EC+%B+ ~ 0.05
228Np 61.4 s %EC=60 7, %A=40 7, %ECSF=0.020 9
229Np 4.0 m %A > 50, %EC < 50
230Np 4.6 m %EC+%B+ < 97, %A > 3
231Np 48.8 m (5/2) %EC=98 1, %A=2 1
232Np 14.7 m (4+) %EC+%B+=100
233Np 36.2 m (5/2+) %EC=100, %A < 0.001
234Np 4.4 d(0+) %EC+%B+=100
235Np 396.1 d 5/2+ %EC=99.99740 13, %A=0.00260 13
236Np 1.54e5 y(6-) %EC=87.3 5, %B-=12.5 5, %A=0.16 4
236m1Np 22.5 h 1 %EC=52 1, %B-=48 1
237Np 2.144e+6 y 5/2+ %A=100, %SF < 2E-10
237m1Np 45 ns
238Np 2.117 d 2+ %B-=100
238m1Np 112 ns
239Np 2.3565 d 5/2+ %B-=100
240Np 61.9 m(5+) %B-=100
240m1Np 7.22 m1(+) %B-=99.89 3, %IT=0.11 3
241Np 13.9 m (5/2+) %B-=100
242Np 5.5 m(6) %B-=100
242m1Np 2.2 m(1+) %B-=100
243Np 1.8 m(5/2-) %B-=100
244Np 2.29 m(7-) %B-=100
Isotope Explorer Nuclear Structure and Decay Data
8th Edition of the Table of Isotopes
Isotopes Project Home Page
Lawrence Berkeley National Laboratory
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