Isotopes of berkelium

Berkelium (97Bk) is an artificial element, and thus a standard atomic weight cannot be given. Like all artificial elements, it has no stable isotopes. The first isotope to be synthesized was 243Bk in 1949. There are twenty known radioisotopes, from 233Bk and 233Bk to 253Bk (except 235Bk and 237Bk), and six nuclear isomers. The longest-lived isotope is 247Bk with a half-life of 1,380 years.

List of isotopes

 * rowspan=2|233Bk
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2 style="text-align:right" | 136
 * rowspan=2|233.05665(25)#
 * rowspan=2|40(30) s
 * α
 * 229Am
 * rowspan=2|3/2-#
 * β+?
 * 233Cm
 * rowspan=3|234Bk
 * rowspan=3 style="text-align:right" | 97
 * rowspan=3 style="text-align:right" | 137
 * rowspan=3|234.05732(16)#
 * rowspan=3|20(5) s
 * α (>80%)
 * 230Am
 * rowspan=3|3-#
 * β+ (<20%)
 * 234Cm
 * β+, SF?
 * (various)
 * rowspan=3|236Bk
 * rowspan=3 style="text-align:right" | 97
 * rowspan=3 style="text-align:right" | 139
 * rowspan=3|236.05748(39)#
 * rowspan=3|26(10) s
 * β+ (99.96%)
 * 236Cm
 * rowspan=2|4+#
 * β+, SF (0.04%)
 * (various)
 * α?
 * 232Am
 * rowspan=3|238Bk
 * rowspan=3 style="text-align:right" | 97
 * rowspan=3 style="text-align:right" | 141
 * rowspan=3|238.05820(28)#
 * rowspan=3|2.40(8) min
 * β+ (99.95%)
 * 238Cm
 * rowspan=3| 1#
 * β+, SF (0.048%)
 * (various)
 * α?
 * 234Am
 * rowspan=3|239Bk
 * rowspan=3 style="text-align:right" | 97
 * rowspan=3 style="text-align:right" | 142
 * rowspan=3|239.05824(22)#
 * rowspan=3|100# s
 * β+
 * 239Cm
 * rowspan=3|(7/2+)
 * α?
 * 235Am
 * SF?
 * (various)
 * rowspan=3|240Bk
 * rowspan=3 style="text-align:right" | 97
 * rowspan=3 style="text-align:right" | 143
 * rowspan=3|240.05976(16)#
 * rowspan=3|4.8(8) min
 * β+?
 * 240Cm
 * rowspan=3|7−#
 * β+, SF (0.0020%)
 * (various)
 * α?
 * 236Am
 * rowspan=2|241Bk
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2 style="text-align:right" | 144
 * rowspan=2|241.06010(18)#
 * rowspan=2|4.6(4) min
 * β+?
 * 241Cm
 * rowspan=2|(7/2+)
 * α?
 * 237Am
 * rowspan=3|242Bk
 * rowspan=3 style="text-align:right" | 97
 * rowspan=3 style="text-align:right" | 145
 * rowspan=3|242.06198(22)#
 * rowspan=3|7.0(13) min
 * β+
 * 242Cm
 * rowspan=3|3+#
 * β+, SF (<3×10−5%)
 * (various)
 * α?
 * 238Am
 * rowspan=2 style="text-indent:1em" | 242mBk
 * rowspan=2 colspan="3" style="text-indent:2em" | 2000(200)# keV
 * rowspan=2|600(100) ns
 * SF
 * (various)
 * rowspan=2|
 * IT?
 * 242Bk
 * rowspan=2|243Bk
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2 style="text-align:right" | 146
 * rowspan=2|243.0630059(49)
 * rowspan=2|4.6(2) h
 * β+ (99.85%)
 * 243Cm
 * rowspan=2|3/2−
 * α (.15%)
 * 239Am
 * rowspan=2|244Bk
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2 style="text-align:right" | 147
 * rowspan=2|244.065179(15)
 * rowspan=2|5.02(3) h
 * β+?
 * 244Cm
 * rowspan=2|4−
 * α (0.006%)
 * 240Am
 * rowspan=2 style="text-indent:1em" | 244mBk
 * rowspan=2 colspan="3" style="text-indent:2em" | 1500(500)# keV
 * rowspan=2|820(60) ns
 * SF
 * (various)
 * rowspan=2|
 * IT?
 * 244Bk
 * rowspan=2|245Bk
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2 style="text-align:right" | 148
 * rowspan=2|245.0663598(19)
 * rowspan=2|4.95(3) d
 * EC (99.88%)
 * 245Cm
 * rowspan=2|3/2−
 * α (.12%)
 * 241Am
 * rowspan=2|246Bk
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2 style="text-align:right" | 149
 * rowspan=2|246.068671(64)
 * rowspan=2|1.80(2) d
 * β+
 * 246Cm
 * rowspan=2|2(−)
 * α?
 * 242Am
 * rowspan=2|247Bk
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2 style="text-align:right" | 150
 * rowspan=2|247.0703059(56)
 * rowspan=2|1.38(25)×103 y
 * α
 * 243Am
 * rowspan=2|3/2−
 * SF?
 * (various)
 * rowspan=2|248Bk
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2 style="text-align:right" | 151
 * rowspan=2|248.073142(54)
 * rowspan=2|>9 y
 * α?
 * 244Am
 * rowspan=2|6+#
 * EC?
 * 248Cm
 * rowspan=3 style="text-indent:1em" | 248mBk
 * rowspan=3 colspan="3" style="text-indent:2em" | −20(50) keV
 * rowspan=3| 23.7(2) h
 * β− (70%)
 * 248Cf
 * rowspan=3| 1(−)
 * EC (30%)
 * 248Cm
 * α?
 * 244Am
 * rowspan=3|249Bk
 * rowspan=3 style="text-align:right" | 97
 * rowspan=3 style="text-align:right" | 152
 * rowspan=3|249.0749831(13)
 * rowspan=3|327.2(3) d
 * β−
 * 249Cf
 * rowspan=3|7/2+
 * α (.00145%)
 * 245Am
 * SF (4.7×10−8%)
 * (various)
 * style="text-indent:1em" | 249mBk
 * colspan="3" style="text-indent:2em" | 8.777(14) keV
 * 300 μs
 * IT
 * 249Bk
 * 3/2−
 * 250Bk
 * style="text-align:right" | 97
 * style="text-align:right" | 153
 * 250.0783172(31)
 * 3.212(5) h
 * β−
 * 250Cf
 * 2−
 * style="text-indent:1em" | 250m1Bk
 * colspan="3" style="text-indent:2em" | 35.59(10) keV
 * 29(1) μs
 * IT
 * 250Bk
 * 4+
 * style="text-indent:1em" | 250m2Bk
 * colspan="3" style="text-indent:2em" | 85.6(16) keV
 * 213(8) μs
 * IT
 * 250Bk
 * 7+
 * 251Bk
 * style="text-align:right" | 97
 * style="text-align:right" | 154
 * 251.080761(12)
 * 55.6(11) min
 * β−
 * 251Cf
 * (3/2−)
 * style="text-indent:1em" | 251mBk
 * colspan="3" style="text-indent:2em" | 35.5(13) keV
 * 58(4) μs
 * IT
 * 251Bk
 * (7/2+)
 * rowspan=2|252Bk
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2 style="text-align:right" | 155
 * rowspan=2|252.08431(22)#
 * rowspan=2|1.8(5) min
 * β−?
 * 252Cf
 * rowspan=2|
 * α?
 * 248Am
 * 253Bk
 * style="text-align:right" | 97
 * style="text-align:right" | 156
 * 253.08688(39)#
 * 60# min
 * β−?
 * 253Cf
 * 3/2-#
 * 250Cf
 * 2−
 * style="text-indent:1em" | 250m1Bk
 * colspan="3" style="text-indent:2em" | 35.59(10) keV
 * 29(1) μs
 * IT
 * 250Bk
 * 4+
 * style="text-indent:1em" | 250m2Bk
 * colspan="3" style="text-indent:2em" | 85.6(16) keV
 * 213(8) μs
 * IT
 * 250Bk
 * 7+
 * 251Bk
 * style="text-align:right" | 97
 * style="text-align:right" | 154
 * 251.080761(12)
 * 55.6(11) min
 * β−
 * 251Cf
 * (3/2−)
 * style="text-indent:1em" | 251mBk
 * colspan="3" style="text-indent:2em" | 35.5(13) keV
 * 58(4) μs
 * IT
 * 251Bk
 * (7/2+)
 * rowspan=2|252Bk
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2 style="text-align:right" | 155
 * rowspan=2|252.08431(22)#
 * rowspan=2|1.8(5) min
 * β−?
 * 252Cf
 * rowspan=2|
 * α?
 * 248Am
 * 253Bk
 * style="text-align:right" | 97
 * style="text-align:right" | 156
 * 253.08688(39)#
 * 60# min
 * β−?
 * 253Cf
 * 3/2-#
 * style="text-align:right" | 97
 * style="text-align:right" | 156
 * 253.08688(39)#
 * 60# min
 * β−?
 * 253Cf
 * 3/2-#