text:
Isotopes of erbium

Naturally occurring erbium (68Er) is composed of six stable isotopes, with 166Er being the most abundant (33.503% natural abundance). Thirty-nine radioisotopes have been characterized with between 74 and 112 neutrons, or 142 to 180 nucleons, with the most stable being 169Er with a half-life of 9.4 days, 172Er with a half-life of 49.3 hours, 160Er with a half-life of 28.58 hours, 165Er with a half-life of 10.36 hours, and 171Er with a half-life of 7.516 hours. All of the remaining radioactive isotopes have half-lives that are less than 3.5 hours, and the majority of these have half-lives that are less than 4 minutes. This element also has numerous meta states, with the most stable being 167mEr (t1/2 2.269 seconds).

The isotopes of erbium range in atomic weight from 141.9723 u (142Er) to 179.9644 u (180Er). The primary decay mode before the most abundant stable isotope, 166Er, is electron capture, and the primary mode after is beta decay. The primary decay products before 166Er are holmium isotopes, and the primary products after are thulium isotopes. All isotopes of erbium are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed.

List of isotopes

 * 142Er
 * style="text-align:right" | 68
 * style="text-align:right" | 74
 * 141.97002(54)#
 * 10# μs
 * p
 * 141Ho
 * 0+
 * rowspan=2| 143Er
 * style="text-align:right" rowspan=2| 68
 * style="text-align:right" rowspan=2| 75
 * rowspan=2| 142.96655(43)#
 * rowspan=2| 200# ms
 * β+
 * 143Ho
 * rowspan=2|9/2−#
 * rowspan=2|
 * rowspan=2|
 * β+, p
 * 142Dy
 * 144Er
 * style="text-align:right" | 68
 * style="text-align:right" | 76
 * 143.96070(21)#
 * 400# ms [>200 ns]
 * β+
 * 144Ho
 * 0+
 * rowspan=2| 145Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 77
 * rowspan=2| 144.95787(22)#
 * rowspan=2| 900(200) ms
 * β+
 * 145Ho
 * rowspan=2|1/2+#
 * rowspan=2|
 * rowspan=2|
 * β+, p (rare)
 * 144Dy
 * rowspan=3 style="text-indent:1em" | 145mEr
 * rowspan=3 colspan="3" style="text-indent:2em" | 205(4)# keV
 * rowspan=3| 1.0(3) s
 * β+
 * 145Ho
 * rowspan=3| (11/2-)
 * rowspan=3|
 * rowspan=3|
 * IT (rare)
 * 145Er
 * β+, p (rare)
 * 144Dy
 * rowspan=2|146Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 78
 * rowspan=2|145.952418(7)
 * rowspan=2|1.7(6) s
 * β+
 * 146Ho
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β+, p (rare)
 * 145Dy
 * rowspan=2|147Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 79
 * rowspan=2|146.94996(4)#
 * rowspan=2|3.2(1.2) s
 * β+
 * 147Ho
 * rowspan=2|(1/2+)
 * rowspan=2|
 * rowspan=2|
 * β+, p (rare)
 * 146Dy
 * rowspan=2 style="text-indent:1em" | 147mEr
 * rowspan=2 colspan="3" style="text-indent:2em" | 100(50)# keV
 * rowspan=2| 1.6(2) s
 * β+
 * 147Ho
 * rowspan=2| (11/2−)
 * rowspan=2|
 * rowspan=2|
 * β+, p (rare)
 * 146Dy
 * rowspan=2|148Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 80
 * rowspan=2|147.944735(11)#
 * rowspan=2|4.6(2) s
 * β+ (99.85%)
 * 148Ho
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β+, p (.15%)
 * 147Dy
 * style="text-indent:1em" | 148mEr
 * colspan="3" style="text-indent:2em" | 2.9132(4) MeV
 * 13(3) μs
 * IT
 * 148Er
 * (10+)
 * rowspan=2|149Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 81
 * rowspan=2|148.94231(3)
 * rowspan=2|4(2) s
 * β+ (92.8%)
 * 149Ho
 * rowspan=2|(1/2+)
 * rowspan=2|
 * rowspan=2|
 * β+, p (7.2%)
 * 148Dy
 * rowspan=3 style="text-indent:1em" | 149m1Er
 * rowspan=3 colspan="3" style="text-indent:2em" | 741.8(2) keV
 * rowspan=3|8.9(2) s
 * β+ (96.5%)
 * 149Ho
 * rowspan=3|(11/2−)
 * rowspan=3|
 * rowspan=3|
 * IT (3.5%)
 * 149Er
 * β+, p (.18%)
 * 148Dy
 * style="text-indent:1em" | 149m2Er
 * colspan="3" style="text-indent:2em" | 2.6111(3) MeV
 * 0.61(8) μs
 * IT
 * 149Er
 * (19/2+)
 * style="text-indent:1em" | 149m3Er
 * colspan="3" style="text-indent:2em" | 3.302(7) MeV
 * 4.8(1) μs
 * IT
 * 149Er
 * (27/2−)
 * 150Er
 * style="text-align:right" | 68
 * style="text-align:right" | 82
 * 149.937916(18)
 * 18.5(7) s
 * β+
 * 150Ho
 * 0+
 * style="text-indent:1em" | 150mEr
 * colspan="3" style="text-indent:2em" | 2.7965(5) MeV
 * 2.55(10) μs
 * IT
 * 150Er
 * 10+
 * 151Er
 * style="text-align:right" | 68
 * style="text-align:right" | 83
 * 150.937449(18)
 * 23.5(20) s
 * β+
 * 151Ho
 * (7/2−)
 * rowspan=2 style="text-indent:1em" | 151m1Er
 * rowspan=2 colspan="3" style="text-indent:2em" | 2.5860(5) MeV
 * rowspan=2|580(20) ms
 * IT (95.3%)
 * 151Er
 * rowspan=2|(27/2−)
 * rowspan=2|
 * rowspan=2|
 * β+ (4.7%)
 * 151Ho
 * style="text-indent:1em" | 151m2Er
 * colspan="3" style="text-indent:2em" | 10.2866(10) MeV
 * 0.42(5) μs
 * IT
 * 151Er
 * (65/2-, 61/2+)
 * rowspan=2|152Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 84
 * rowspan=2|151.935050(9)
 * rowspan=2|10.3(1) s
 * α (90%)
 * 148Dy
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β+ (10%)
 * 152Ho
 * rowspan=2|153Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 85
 * rowspan=2|152.935086(10)
 * rowspan=2|37.1(2) s
 * α (53%)
 * 149Dy
 * rowspan=2|7/2(−)
 * rowspan=2|
 * rowspan=2|
 * β+ (47%)
 * 153Ho
 * style="text-indent:1em" | 153m1Er
 * colspan="3" style="text-indent:2em" | 2.7982(10) MeV
 * 373(9) ns
 * IT
 * 153Er
 * (27/2-)
 * style="text-indent:1em" | 153m2Er
 * colspan="3" style="text-indent:2em" | 5.2481(10) MeV
 * 248(32) ns
 * IT
 * 153Er
 * (41/2-)
 * rowspan=2|154Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 86
 * rowspan=2|153.932791(5)
 * rowspan=2|3.73(9) min
 * β+ (99.53%)
 * 154Ho
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * α (.47%)
 * 150Dy
 * rowspan=2|155Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 87
 * rowspan=2|154.933216(7)
 * rowspan=2|5.3(3) min
 * β+ (99.978%)
 * 155Ho
 * rowspan=2|7/2−
 * rowspan=2|
 * rowspan=2|
 * α (.022%)
 * 151Dy
 * rowspan=2| 156Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 88
 * rowspan=2| 155.931066(26)
 * rowspan=2| 19.5(10) min
 * β+
 * 156Ho
 * rowspan=2| 0+
 * rowspan=2|
 * rowspan=2|
 * α (1.2%)
 * 152Dy
 * 157Er
 * style="text-align:right" | 68
 * style="text-align:right" | 89
 * 156.931923(28)
 * 18.65(10) min
 * β+
 * 157Ho
 * 3/2−
 * style="text-indent:1em" | 157mEr
 * colspan="3" style="text-indent:2em" | 155.4(3) keV
 * 76(6) ms
 * IT
 * 157Er
 * (9/2+)
 * 158Er
 * style="text-align:right" | 68
 * style="text-align:right" | 90
 * 157.929893(27)
 * 2.29(6) h
 * EC
 * 158Ho
 * 0+
 * 159Er
 * style="text-align:right" | 68
 * style="text-align:right" | 91
 * 158.930691(4)
 * 36(1) min
 * β+
 * 159Ho
 * 3/2−
 * style="text-indent:1em" | 159m1Er
 * colspan="3" style="text-indent:2em" | 182.602(24) keV
 * 337(14) ns
 * IT
 * 159Er
 * 9/2+
 * style="text-indent:1em" | 159m2Er
 * colspan="3" style="text-indent:2em" | 429.05(3) keV
 * 590(60) ns
 * IT
 * 159Er
 * 11/2−
 * 160Er
 * style="text-align:right" | 68
 * style="text-align:right" | 92
 * 159.929077(26)
 * 28.58(9) h
 * EC
 * 160Ho
 * 0+
 * 161Er
 * style="text-align:right" | 68
 * style="text-align:right" | 93
 * 160.930004(9)
 * 3.21(3) h
 * β+
 * 161Ho
 * 3/2−
 * style="text-indent:1em" | 161mEr
 * colspan="3" style="text-indent:2em" | 396.44(4) keV
 * 7.5(7) μs
 * IT
 * 161Er
 * 11/2−
 * 162Er
 * style="text-align:right" | 68
 * style="text-align:right" | 94
 * 161. 9287873(8)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 0.00139(5)
 * style="text-indent:1em" | 162mEr
 * colspan="3" style="text-indent:2em" | 2.02601(13) MeV
 * 88(16) ns
 * IT
 * 162Er
 * (7-)
 * 163Er
 * style="text-align:right" | 68
 * style="text-align:right" | 95
 * 162.930040(5)
 * 75.0(4) min
 * β+
 * 163Ho
 * 5/2−
 * style="text-indent:1em" | 163mEr
 * colspan="3" style="text-indent:2em" | 445.5(6) keV
 * 580(100) ns
 * IT
 * 163Er
 * (11/2−)
 * 164Er
 * style="text-align:right" | 68
 * style="text-align:right" | 96
 * 163.9292077(8)
 * colspan=3 align=center|Observationally Stable '''
 * 0+
 * 0.01601(3)
 * 165Er
 * style="text-align:right" | 68
 * style="text-align:right" | 97
 * 164.9307335(10)
 * 10.36(4) h
 * EC
 * 165Ho
 * 5/2−
 * style="text-indent:1em" | 165m1Er
 * colspan="3" style="text-indent:2em" | 551.3(6) keV
 * 250(30)ns
 * IT
 * 165Er
 * 11/2-
 * style="text-indent:1em" | 165m2Er
 * colspan="3" style="text-indent:2em" | 1.8230(6) MeV
 * 370(40)ns
 * IT
 * 165Er
 * (19/2)
 * 166Er
 * style="text-align:right" | 68
 * style="text-align:right" | 98
 * 165.9303011(4)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 0.33503(36)
 * 167Er
 * style="text-align:right" | 68
 * style="text-align:right" | 99
 * 166.9320562(3)
 * colspan=3 align=center|Observationally Stable
 * 7/2+
 * 0.22869(9)
 * style="text-indent:1em" | 167mEr
 * colspan="3" style="text-indent:2em" | 207.801(5) keV
 * 2.269(6) s
 * IT
 * 167Er
 * 1/2−
 * 168Er
 * style="text-align:right" | 68
 * style="text-align:right" | 100
 * 167.93237828(28)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 0.26978(18)
 * style="text-indent:1em" | 168mEr
 * colspan="3" style="text-indent:2em" | 1.0940383(16) MeV
 * 109.0(7) ns
 * IT
 * 168Er
 * 4-
 * 169Er
 * style="text-align:right" | 68
 * style="text-align:right" | 101
 * 168.9345984(3)
 * 9.392(18) d
 * β−
 * 169Tm
 * 1/2−
 * style="text-indent:1em" | 169m1Er
 * colspan="3" style="text-indent:2em" | 92.05(10) keV
 * 285(20) ns
 * IT
 * 169Er
 * (5/2-)
 * style="text-indent:1em" | 169m2Er
 * colspan="3" style="text-indent:2em" | 243.69(17) keV
 * 200(10) ns
 * IT
 * 169Er
 * 7/2+
 * 170Er
 * style="text-align:right" | 68
 * style="text-align:right" | 102
 * 169.9354719(15)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 0.14910(36)
 * 171Er
 * style="text-align:right" | 68
 * style="text-align:right" | 103
 * 170.93803746(15)
 * 7.516(2) h
 * β−
 * 171Tm
 * 5/2−
 * style="text-indent:1em" | 171mEr
 * colspan="3" style="text-indent:2em" | 198.61(9) keV|
 * 210(10) ns
 * IT
 * 171Er
 * 1/2−
 * 172Er
 * style="text-align:right" | 68
 * style="text-align:right" | 104
 * 171.939363(4)
 * 49.3(5) h
 * β−
 * 172Tm
 * 0+
 * style="text-indent:1em" | 172mEr
 * colspan="3" style="text-indent:2em" | 1.5009(3) MeV
 * 579(62) ns
 * IT
 * 172Er
 * (6+)
 * 173Er
 * style="text-align:right" | 68
 * style="text-align:right" | 105
 * 172.94240(21)#
 * 1.434(17) min
 * β−
 * 173Tm
 * (7/2−)
 * 174Er
 * style="text-align:right" | 68
 * style="text-align:right" | 106
 * 173.94423(32)#
 * 3.2(2) min
 * β−
 * 174Tm
 * 0+
 * style="text-indent:1em" | 174mEr
 * colspan="3" style="text-indent:2em" | 1.1115(7) MeV
 * 3.9(3) s
 * IT
 * 174Er
 * 8-
 * 175Er
 * style="text-align:right" | 68
 * style="text-align:right" | 107
 * 174.94777(43)#
 * 1.2(3) min
 * β−
 * 175Tm
 * 9/2+#
 * 176Er
 * style="text-align:right" | 68
 * style="text-align:right" | 108
 * 175.94994(43)#
 * 12# s (>300 ns)
 * β−
 * 176Tm
 * 0+
 * 177Er
 * style="text-align:right" | 68
 * style="text-align:right" | 109
 * 176.95399(54)#
 * 8# s (>300 ns)
 * β−
 * 177Tm
 * 1/2−#
 * 178Er
 * style="text-align:right" | 68
 * style="text-align:right" | 110
 * 177.95678(64)#
 * 4# s (>300 ns)
 * β−
 * 178Tm
 * 0+
 * rowspan=2| 179Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 111
 * rowspan=2| 178.96127(54)#
 * rowspan=2| 3# s (>550 ns)
 * β−
 * 179Tm
 * rowspan=2| 3/2−#
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 178Tm
 * rowspan=2| 180Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 112
 * rowspan=2| 179.96438(54)#
 * rowspan=2| 2# s (>550 ns)
 * β−
 * 180Tm
 * rowspan=2| 0+
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 179Tm
 * 169Tm
 * 1/2−
 * style="text-indent:1em" | 169m1Er
 * colspan="3" style="text-indent:2em" | 92.05(10) keV
 * 285(20) ns
 * IT
 * 169Er
 * (5/2-)
 * style="text-indent:1em" | 169m2Er
 * colspan="3" style="text-indent:2em" | 243.69(17) keV
 * 200(10) ns
 * IT
 * 169Er
 * 7/2+
 * 170Er
 * style="text-align:right" | 68
 * style="text-align:right" | 102
 * 169.9354719(15)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 0.14910(36)
 * 171Er
 * style="text-align:right" | 68
 * style="text-align:right" | 103
 * 170.93803746(15)
 * 7.516(2) h
 * β−
 * 171Tm
 * 5/2−
 * style="text-indent:1em" | 171mEr
 * colspan="3" style="text-indent:2em" | 198.61(9) keV|
 * 210(10) ns
 * IT
 * 171Er
 * 1/2−
 * 172Er
 * style="text-align:right" | 68
 * style="text-align:right" | 104
 * 171.939363(4)
 * 49.3(5) h
 * β−
 * 172Tm
 * 0+
 * style="text-indent:1em" | 172mEr
 * colspan="3" style="text-indent:2em" | 1.5009(3) MeV
 * 579(62) ns
 * IT
 * 172Er
 * (6+)
 * 173Er
 * style="text-align:right" | 68
 * style="text-align:right" | 105
 * 172.94240(21)#
 * 1.434(17) min
 * β−
 * 173Tm
 * (7/2−)
 * 174Er
 * style="text-align:right" | 68
 * style="text-align:right" | 106
 * 173.94423(32)#
 * 3.2(2) min
 * β−
 * 174Tm
 * 0+
 * style="text-indent:1em" | 174mEr
 * colspan="3" style="text-indent:2em" | 1.1115(7) MeV
 * 3.9(3) s
 * IT
 * 174Er
 * 8-
 * 175Er
 * style="text-align:right" | 68
 * style="text-align:right" | 107
 * 174.94777(43)#
 * 1.2(3) min
 * β−
 * 175Tm
 * 9/2+#
 * 176Er
 * style="text-align:right" | 68
 * style="text-align:right" | 108
 * 175.94994(43)#
 * 12# s (>300 ns)
 * β−
 * 176Tm
 * 0+
 * 177Er
 * style="text-align:right" | 68
 * style="text-align:right" | 109
 * 176.95399(54)#
 * 8# s (>300 ns)
 * β−
 * 177Tm
 * 1/2−#
 * 178Er
 * style="text-align:right" | 68
 * style="text-align:right" | 110
 * 177.95678(64)#
 * 4# s (>300 ns)
 * β−
 * 178Tm
 * 0+
 * rowspan=2| 179Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 111
 * rowspan=2| 178.96127(54)#
 * rowspan=2| 3# s (>550 ns)
 * β−
 * 179Tm
 * rowspan=2| 3/2−#
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 178Tm
 * rowspan=2| 180Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 112
 * rowspan=2| 179.96438(54)#
 * rowspan=2| 2# s (>550 ns)
 * β−
 * 180Tm
 * rowspan=2| 0+
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 179Tm
 * style="text-align:right" | 68
 * style="text-align:right" | 109
 * 176.95399(54)#
 * 8# s (>300 ns)
 * β−
 * 177Tm
 * 1/2−#
 * 178Er
 * style="text-align:right" | 68
 * style="text-align:right" | 110
 * 177.95678(64)#
 * 4# s (>300 ns)
 * β−
 * 178Tm
 * 0+
 * rowspan=2| 179Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 111
 * rowspan=2| 178.96127(54)#
 * rowspan=2| 3# s (>550 ns)
 * β−
 * 179Tm
 * rowspan=2| 3/2−#
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 178Tm
 * rowspan=2| 180Er
 * rowspan=2 style="text-align:right" | 68
 * rowspan=2 style="text-align:right" | 112
 * rowspan=2| 179.96438(54)#
 * rowspan=2| 2# s (>550 ns)
 * β−
 * 180Tm
 * rowspan=2| 0+
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 179Tm
 * rowspan=2| 2# s (>550 ns)
 * β−
 * 180Tm
 * rowspan=2| 0+
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 179Tm
 * 179Tm

title: Isotopes of erbium


text:
Isotopes of holmium

Natural holmium (67Ho) contains one observationally stable isotope, 165Ho. The below table lists 36 isotopes spanning 140Ho through 175Ho as well as 33 nuclear isomers. Among the known synthetic radioactive isotopes; the most stable one is 163Ho, with a half-life of 4,570 years. All other radioisotopes have half-lives not greater than 1.117 days in their ground states (although the metastable 166m1Ho has a half-life of about 1,200 years), and most have half-lives under 3 hours.

List of isotopes

 * 140Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 73
 * 139.96854(54)#
 * 6(3) ms
 * 8+#
 * 141Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 74
 * 140.96310(54)#
 * 4.1(3) ms
 * (7/2−)
 * style="text-indent:1em" | 141mHo
 * colspan="3" style="text-indent:2em" | 66(2) keV
 * 6.4(8) μs
 * (1/2+)
 * rowspan=2|142Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 75
 * rowspan=2|141.95977(54)#
 * rowspan=2|400(100) ms
 * β+
 * 142Dy
 * rowspan=2|(6 to 9)
 * rowspan=2|
 * p
 * 141Dy
 * 143Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 76
 * 142.95461(43)#
 * 300# ms [>200 ns]
 * β+
 * 143Dy
 * 11/2−#
 * rowspan=2|144Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 77
 * rowspan=2|143.95148(32)#
 * rowspan=2|0.7(1) s
 * β+
 * 144Dy
 * rowspan=2|
 * rowspan=2|
 * β+, p
 * 143Tb
 * 145Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 78
 * 144.94720(32)#
 * 2.4(1) s
 * β+
 * 145Dy
 * (11/2−)
 * style="text-indent:1em" | 145mHo
 * colspan="3" style="text-indent:2em" | 100(100)# keV
 * 100# ms
 * 5/2+#
 * rowspan=2|146Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 79
 * rowspan=2|145.94464(21)#
 * rowspan=2|3.6(3) s
 * β+
 * 146Dy
 * rowspan=2|(10+)
 * rowspan=2|
 * β+, p (rare)
 * 145Tb
 * rowspan=2|147Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 80
 * rowspan=2|146.94006(3)
 * rowspan=2|5.8(4) s
 * β+
 * 147Dy
 * rowspan=2|(11/2−)
 * rowspan=2|
 * β+, p (rare)
 * 146Tb
 * 148Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 81
 * 147.93772(14)
 * 2.2(11) s
 * β+
 * 148Dy
 * (1+)
 * rowspan=2 style="text-indent:1em" | 148m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 400(100)# keV
 * rowspan=2|9.49(12) s
 * β+ (99.92%)
 * 148Dy
 * rowspan=2|(6)−
 * rowspan=2|
 * β+, p (.08%)
 * 147Tb
 * style="text-indent:1em" | 148m2Ho
 * colspan="3" style="text-indent:2em" | 690(100)# keV
 * 2.35(4) ms
 * (10+)
 * 149Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 82
 * 148.933775(20)
 * 21.1(2) s
 * β+
 * 149Dy
 * (11/2−)
 * style="text-indent:1em" | 149m1Ho
 * colspan="3" style="text-indent:2em" | 48.80(20) keV
 * 56(3) s
 * β+
 * 149Dy
 * (1/2+)
 * style="text-indent:1em" | 149m2Ho
 * colspan="3" style="text-indent:2em" | 7200(350) keV
 * >=100 ns
 * 150Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 83
 * 149.933496(15)
 * 76.8(18) s
 * β+
 * 150Dy
 * 2−
 * style="text-indent:1em" | 150m1Ho
 * colspan="3" style="text-indent:2em" | −10(50) keV
 * 23.3(3) s
 * β+
 * 150Dy
 * (9)+
 * style="text-indent:1em" | 150m2Ho
 * colspan="3" style="text-indent:2em" | ~8000 keV
 * 751 ns
 * rowspan=2|151Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 84
 * rowspan=2|150.931688(13)
 * rowspan=2|35.2(1) s
 * β+ (78%)
 * 151Dy
 * rowspan=2|11/2(−)
 * rowspan=2|
 * α (22%)
 * 147Tb
 * rowspan=2 style="text-indent:1em" | 151mHo
 * rowspan=2 colspan="3" style="text-indent:2em" | 41.0(2) keV
 * rowspan=2|47.2(10) s
 * α (77%)
 * 147Tb
 * rowspan=2|1/2(+)
 * rowspan=2|
 * β+ (22%)
 * 151Dy
 * rowspan=2|152Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 85
 * rowspan=2|151.931714(15)
 * rowspan=2|161.8(3) s
 * β+ (88%)
 * 152Dy
 * rowspan=2|2−
 * rowspan=2|
 * α (12%)
 * 148Tb
 * style="text-indent:1em" | 152m1Ho
 * colspan="3" style="text-indent:2em" | 160(1) keV
 * 50.0(4) s
 * 9+
 * style="text-indent:1em" | 152m2Ho
 * colspan="3" style="text-indent:2em" | 3019.59(19) keV
 * 8.4(3) μs
 * 19−
 * rowspan=2|153Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 86
 * rowspan=2|152.930199(6)
 * rowspan=2|2.01(3) min
 * β+ (99.94%)
 * 153Dy
 * rowspan=2|11/2−
 * rowspan=2|
 * α (.05%)
 * 149Tb
 * rowspan=2 style="text-indent:1em" | 153m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 68.7(3) keV
 * rowspan=2|9.3(5) min
 * β+ (99.82%)
 * 153Dy
 * rowspan=2|1/2+
 * rowspan=2|
 * α (.18%)
 * 149Tb
 * style="text-indent:1em" | 153m2Ho
 * colspan="3" style="text-indent:2em" | 2772 keV
 * 229(2) ns
 * (31/2+)
 * rowspan=2|154Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 87
 * rowspan=2|153.930602(9)
 * rowspan=2|11.76(19) min
 * β+ (99.98%)
 * 154Dy
 * rowspan=2|2−
 * rowspan=2|
 * α (.02%)
 * 150Tb
 * rowspan=3 style="text-indent:1em" | 154mHo
 * rowspan=3 colspan="3" style="text-indent:2em" | 238(30) keV
 * rowspan=3|3.10(14) min
 * β+ (99.99%)
 * 154Dy
 * rowspan=3|8+
 * rowspan=3|
 * α (.001%)
 * 150Tb
 * IT (rare)
 * 154Ho
 * 155Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 88
 * 154.929103(19)
 * 48(1) min
 * β+
 * 155Dy
 * 5/2+
 * style="text-indent:1em" | 155mHo
 * colspan="3" style="text-indent:2em" | 141.97(11) keV
 * 880(80) μs
 * 11/2−
 * 156Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 89
 * 155.92984(5)
 * 56(1) min
 * β+
 * 156Dy
 * 4−
 * rowspan=2 style="text-indent:1em" | 156m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 100(50)# keV
 * rowspan=2|7.8(3) min
 * β+
 * 156Dy
 * rowspan=2|(9+)
 * rowspan=2|
 * IT
 * 156Ho
 * style="text-indent:1em" | 156m2Ho
 * colspan="3" style="text-indent:2em" | 52.4(5) keV
 * 9.5(15) s
 * 1−
 * 157Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 90
 * 156.928256(26)
 * 12.6(2) min
 * β+
 * 157Dy
 * 7/2−
 * rowspan=2|158Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 91
 * rowspan=2|157.928941(29)
 * rowspan=2|11.3(4) min
 * β+ (93%)
 * 158Dy
 * rowspan=2|5+
 * rowspan=2|
 * α (7%)
 * 154Tb
 * rowspan=2 style="text-indent:1em" | 158m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 67.200(10) keV
 * rowspan=2|28(2) min
 * IT (81%)
 * 158Ho
 * rowspan=2|2−
 * rowspan=2|
 * β+ (19%)
 * 158Dy
 * style="text-indent:1em" | 158m2Ho
 * colspan="3" style="text-indent:2em" | 180(70)# keV
 * 21.3(23) min
 * (9+)
 * 159Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 92
 * 158.927712(4)
 * 33.05(11) min
 * β+
 * 159Dy
 * 7/2−
 * style="text-indent:1em" | 159mHo
 * colspan="3" style="text-indent:2em" | 205.91(5) keV
 * 8.30(8) s
 * IT
 * 159Ho
 * 1/2+
 * 160Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 93
 * 159.928729(16)
 * 25.6(3) min
 * β+
 * 160Dy
 * 5+
 * rowspan=2 style="text-indent:1em" | 160m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 59.98(3) keV
 * rowspan=2|5.02(5) h
 * IT (65%)
 * 160Ho
 * rowspan=2|2−
 * rowspan=2|
 * β+ (35%)
 * 160Dy
 * style="text-indent:1em" | 160m2Ho
 * colspan="3" style="text-indent:2em" | 197(16) keV
 * 3 s
 * (9+)
 * 161Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 94
 * 160.927855(3)
 * 2.48(5) h
 * EC
 * 161Dy
 * 7/2−
 * style="text-indent:1em" | 161mHo
 * colspan="3" style="text-indent:2em" | 211.16(3) keV
 * 6.76(7) s
 * IT
 * 161Ho
 * 1/2+
 * 162Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 95
 * 161.929096(4)
 * 15.0(10) min
 * β+
 * 162Dy
 * 1+
 * rowspan=2 style="text-indent:1em" | 162mHo
 * rowspan=2 colspan="3" style="text-indent:2em" | 106(7) keV
 * rowspan=2|67.0(7) min
 * IT (62%)
 * 162Ho
 * rowspan=2|6−
 * rowspan=2|
 * β+ (38%)
 * 162Dy
 * 163Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 96
 * 162.9287339(27)
 * 4570(25) y
 * EC
 * 163Dy
 * 7/2−
 * style="text-indent:1em" | 163mHo
 * colspan="3" style="text-indent:2em" | 297.88(7) keV
 * 1.09(3) s
 * IT
 * 163Ho
 * 1/2+
 * rowspan=2|164Ho
 * rowspan=2 style="text-align:right" | 67
 * rowspan=2 style="text-align:right" | 97
 * rowspan=2|163.9302335(30)
 * rowspan=2|29(1) min
 * EC (60%)
 * 164Dy
 * rowspan=2|1+
 * rowspan=2|
 * β− (40%)
 * 164Er
 * style="text-indent:1em" | 164mHo
 * colspan="3" style="text-indent:2em" | 139.77(8) keV
 * 38.0(10) min [37.5(+15−5) min]
 * IT
 * 164Ho
 * 6−
 * 165Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 98
 * 164.9303221(27)
 * colspan=3 align=center|Observationally Stable
 * 7/2−
 * 1.0000
 * 166Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 99
 * 165.9322842(27)
 * 26.83(2) h
 * β−
 * 166Er
 * 0−
 * style="text-indent:1em" | 166m1Ho
 * colspan="3" style="text-indent:2em" | 5.985(18) keV
 * 1200(180) y
 * β−
 * 166Er
 * (7)−
 * style="text-indent:1em" | 166m2Ho
 * colspan="3" style="text-indent:2em" | 190.9052(20) keV
 * 185(15) μs
 * 3+
 * 167Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 100
 * 166.933133(6)
 * 3.003(18) h
 * β−
 * 167Er
 * 7/2−
 * style="text-indent:1em" | 167mHo
 * colspan="3" style="text-indent:2em" | 259.34(11) keV
 * 6.0(10) μs
 * 3/2+
 * 168Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 101
 * 167.93552(3)
 * 2.99(7) min
 * β−
 * 168Er
 * 3+
 * rowspan=2 style="text-indent:1em" | 168m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 59(1) keV
 * rowspan=2|132(4) s
 * IT (99.5%)
 * 168Ho
 * rowspan=2|(6+)
 * rowspan=2|
 * β− (.5%)
 * 168Er
 * style="text-indent:1em" | 168m2Ho
 * colspan="3" style="text-indent:2em" | 143.4(2) keV
 * >4 μs
 * (1)−
 * style="text-indent:1em" | 168m3Ho
 * colspan="3" style="text-indent:2em" | 192.6(2) keV
 * 108(11) ns
 * 1+
 * 169Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 102
 * 168.936872(22)
 * 4.72(10) min
 * β−
 * 169Er
 * 7/2−
 * 170Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 103
 * 169.93962(5)
 * 2.76(5) min
 * β−
 * 170Er
 * 6+#
 * style="text-indent:1em" | 170mHo
 * colspan="3" style="text-indent:2em" | 120(70) keV
 * 43(2) s
 * β−
 * 170Er
 * (1+)
 * 171Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 104
 * 170.94147(64)
 * 53(2) s
 * β−
 * 171Er
 * 7/2−#
 * 172Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 105
 * 171.94482(43)#
 * 25(3) s
 * β−
 * 172Er
 * 173Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 106
 * 172.94729(43)#
 * 10# s
 * β−
 * 173Er
 * 7/2−#
 * 174Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 107
 * 173.95115(54)#
 * 8# s
 * 175Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 108
 * 174.95405(64)#
 * 5# s
 * 7/2−#
 * EC (60%)
 * 164Dy
 * rowspan=2|1+
 * rowspan=2|
 * β− (40%)
 * 164Er
 * style="text-indent:1em" | 164mHo
 * colspan="3" style="text-indent:2em" | 139.77(8) keV
 * 38.0(10) min [37.5(+15−5) min]
 * IT
 * 164Ho
 * 6−
 * 165Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 98
 * 164.9303221(27)
 * colspan=3 align=center|Observationally Stable
 * 7/2−
 * 1.0000
 * 166Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 99
 * 165.9322842(27)
 * 26.83(2) h
 * β−
 * 166Er
 * 0−
 * style="text-indent:1em" | 166m1Ho
 * colspan="3" style="text-indent:2em" | 5.985(18) keV
 * 1200(180) y
 * β−
 * 166Er
 * (7)−
 * style="text-indent:1em" | 166m2Ho
 * colspan="3" style="text-indent:2em" | 190.9052(20) keV
 * 185(15) μs
 * 3+
 * 167Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 100
 * 166.933133(6)
 * 3.003(18) h
 * β−
 * 167Er
 * 7/2−
 * style="text-indent:1em" | 167mHo
 * colspan="3" style="text-indent:2em" | 259.34(11) keV
 * 6.0(10) μs
 * 3/2+
 * 168Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 101
 * 167.93552(3)
 * 2.99(7) min
 * β−
 * 168Er
 * 3+
 * rowspan=2 style="text-indent:1em" | 168m1Ho
 * rowspan=2 colspan="3" style="text-indent:2em" | 59(1) keV
 * rowspan=2|132(4) s
 * IT (99.5%)
 * 168Ho
 * rowspan=2|(6+)
 * rowspan=2|
 * β− (.5%)
 * 168Er
 * style="text-indent:1em" | 168m2Ho
 * colspan="3" style="text-indent:2em" | 143.4(2) keV
 * >4 μs
 * (1)−
 * style="text-indent:1em" | 168m3Ho
 * colspan="3" style="text-indent:2em" | 192.6(2) keV
 * 108(11) ns
 * 1+
 * 169Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 102
 * 168.936872(22)
 * 4.72(10) min
 * β−
 * 169Er
 * 7/2−
 * 170Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 103
 * 169.93962(5)
 * 2.76(5) min
 * β−
 * 170Er
 * 6+#
 * style="text-indent:1em" | 170mHo
 * colspan="3" style="text-indent:2em" | 120(70) keV
 * 43(2) s
 * β−
 * 170Er
 * (1+)
 * 171Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 104
 * 170.94147(64)
 * 53(2) s
 * β−
 * 171Er
 * 7/2−#
 * 172Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 105
 * 171.94482(43)#
 * 25(3) s
 * β−
 * 172Er
 * 173Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 106
 * 172.94729(43)#
 * 10# s
 * β−
 * 173Er
 * 7/2−#
 * 174Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 107
 * 173.95115(54)#
 * 8# s
 * 175Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 108
 * 174.95405(64)#
 * 5# s
 * 7/2−#
 * (1+)
 * 171Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 104
 * 170.94147(64)
 * 53(2) s
 * β−
 * 171Er
 * 7/2−#
 * 172Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 105
 * 171.94482(43)#
 * 25(3) s
 * β−
 * 172Er
 * 173Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 106
 * 172.94729(43)#
 * 10# s
 * β−
 * 173Er
 * 7/2−#
 * 174Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 107
 * 173.95115(54)#
 * 8# s
 * 175Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 108
 * 174.95405(64)#
 * 5# s
 * 7/2−#
 * style="text-align:right" | 107
 * 173.95115(54)#
 * 8# s
 * 175Ho
 * style="text-align:right" | 67
 * style="text-align:right" | 108
 * 174.95405(64)#
 * 5# s
 * 7/2−#
 * style="text-align:right" | 67
 * style="text-align:right" | 108
 * 174.95405(64)#
 * 5# s
 * 7/2−#
 * 7/2−#
 * 7/2−#

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Isotopes of holmium


text:
Talk:Tidewater Railway

Untitled
A lot of this is almost exactly copied in William N. Page!

William Page was its president. So, what is the point of this comment? Constructive suggestions appreciated. Vaoverland 10:34, August 24, 2005 (UTC)

 * I have drastically shortened this article, and suggested reader refer to another Wikipedia article, Building the Virginian Railway, which contains same information as deleted portion. Vaoverland 04:33, 5 October 2005 (UTC)

title: Talk:Tidewater Railway


text:
24 Hours of Zolder

The 24 Hours of Zolder (24 uur van Zolder in Dutch) is a yearly sports car and touring car endurance race held at Circuit Zolder in Belgium.

The race was initially held in 1977, and has run every year except for 1988. In 1989 a GT car won for the first time, and the following year the race joined the calendar of the BBL Cup, which became the Carglass Cup in 1992. The 24 Hours became part of the Belcar championship in 1997 (for a few years named Belgian GT Championship, since 2010 named Belcar Endurance Championship), continuing to be the series' yearly endurance event.

title: 24 Hours of Zolder


text:
John Maloney (U.S. politician)

John F. Maloney (sometimes spelled Malony) (died 1918) was an Alaskan lawyer, businessman, and politician, including the first Mayor of Juneau, Alaska from 1905 to 1906. He came to Juneau in 1885, and by 1900 owned part the Porcupine Trading Company, after the 1898 Porcupine Gold Rush, along with Jack Dalton and Ed Hanley.

Maloney is best known for being one of the founders of the Alaska Electric Light & Power (AEL&P), an important Juneau business since 1893. He was also affiliated with the Treadwell Gold Mine, representing the mine's company in legal issues. Maloney was the president of AEL&P from 1905 until his death.

title: John Maloney (U.S. politician)


text:
User:Dmafackler

/Installing MediaWiki on Solaris 9

title: User:Dmafackler


text:
Isotopes of dysprosium

Naturally occurring dysprosium (66Dy) is composed of 7 stable isotopes, 156Dy, 158Dy, 160Dy, 161Dy, 162Dy, 163Dy and 164Dy, with 164Dy being the most abundant (28.18% natural abundance). Twenty-nine radioisotopes have been characterized, with the most stable being 154Dy with a half-life of 1.4 million years, 159Dy with a half-life of 144.4 days, and 166Dy with a half-life of 81.6 hours. All of the remaining radioactive isotopes have half-lives that are less than 10 hours, and the majority of these have half-lives that are less than 30 seconds. This element also has 12 meta states, with the most stable being 165mDy (half-life 1.257 minutes), 147mDy (half-life 55.7 seconds) and 145mDy (half-life 13.6 seconds).

The primary decay mode before the most abundant stable isotope, 164Dy, is electron capture, and the primary mode after is beta decay. The primary decay products before 164Dy are terbium isotopes, and the primary products after are holmium isotopes. Dysprosium is the heaviest element to have isotopes that are predicted to be stable rather than observationally stable isotopes that are predicted to be radioactive.

List of isotopes

 * 138Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 72
 * 137.96249(64)#
 * 200# ms
 * 0+
 * 139Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 73
 * 138.95954(54)#
 * 600(200) ms
 * 7/2+#
 * 140Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 74
 * 139.95401(54)#
 * 700# ms
 * β+
 * 140Tb
 * 0+
 * style="text-indent:1em" | 140mDy
 * colspan="3" style="text-indent:2em" | 2166.1(5) keV
 * 7.0(5) μs
 * (8−)
 * rowspan=2|141Dy
 * rowspan=2 style="text-align:right" | 66
 * rowspan=2 style="text-align:right" | 75
 * rowspan=2|140.95135(32)#
 * rowspan=2|0.9(2) s
 * β+
 * 141Tb
 * rowspan=2|(9/2−)
 * rowspan=2|
 * rowspan=2|
 * β+, p (rare)
 * 140Gd
 * rowspan=3|142Dy
 * rowspan=3 style="text-align:right" | 66
 * rowspan=3 style="text-align:right" | 76
 * rowspan=3|141.94637(39)#
 * rowspan=3|2.3(3) s
 * β+ (90(4)%)
 * rowspan=2|142Tb
 * rowspan=3|0+
 * rowspan=3|
 * rowspan=3|
 * EC (10(4)%)
 * β+, p (.06%)
 * 141Gd
 * rowspan=2|143Dy
 * rowspan=2 style="text-align:right" | 66
 * rowspan=2 style="text-align:right" | 77
 * rowspan=2|142.94383(21)#
 * rowspan=2|5.6(10) s
 * β+
 * 143Tb
 * rowspan=2|(1/2+)
 * rowspan=2|
 * rowspan=2|
 * β+, p (rare)
 * 142Gd
 * style="text-indent:1em" | 143mDy
 * colspan="3" style="text-indent:2em" | 310.7(6) keV
 * 3.0(3) s
 * (11/2−)
 * rowspan=2|144Dy
 * rowspan=2 style="text-align:right" | 66
 * rowspan=2 style="text-align:right" | 78
 * rowspan=2|143.93925(3)
 * rowspan=2|9.1(4) s
 * β+
 * 144Tb
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β+, p (rare)
 * 143Gd
 * rowspan=2|145Dy
 * rowspan=2 style="text-align:right" | 66
 * rowspan=2 style="text-align:right" | 79
 * rowspan=2|144.93743(5)
 * rowspan=2|9.5(10) s
 * β+
 * 145Tb
 * rowspan=2|(1/2+)
 * rowspan=2|
 * rowspan=2|
 * β+, p (rare)
 * 144Gd
 * style="text-indent:1em" | 145mDy
 * colspan="3" style="text-indent:2em" | 118.2(2) keV
 * 14.1(7) s
 * β+
 * 145Tb
 * (11/2−)
 * 146Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 80
 * 145.932845(29)
 * 33.2(7) s
 * β+
 * 146Tb
 * 0+
 * style="text-indent:1em" | 146mDy
 * colspan="3" style="text-indent:2em" | 2935.7(6) keV
 * 150(20) ms
 * IT
 * 146Dy
 * (10+)#
 * rowspan=2|147Dy
 * rowspan=2 style="text-align:right" | 66
 * rowspan=2 style="text-align:right" | 81
 * rowspan=2|146.931092(21)
 * rowspan=2|40(10) s
 * β+ (99.95%)
 * 147Tb
 * rowspan=2|1/2+
 * rowspan=2|
 * rowspan=2|
 * β+, p (.05%)
 * 146Tb
 * rowspan=2 style="text-indent:1em" | 147m1Dy
 * rowspan=2 colspan="3" style="text-indent:2em" | 750.5(4) keV
 * rowspan=2|55(1) s
 * β+ (65%)
 * 147Tb
 * rowspan=2|11/2−
 * rowspan=2|
 * rowspan=2|
 * IT (35%)
 * 147Dy
 * style="text-indent:1em" | 147m2Dy
 * colspan="3" style="text-indent:2em" | 3407.2(8) keV
 * 0.40(1) μs
 * (27/2−)
 * 148Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 82
 * 147.927150(11)
 * 3.3(2) min
 * β+
 * 148Tb
 * 0+
 * 149Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 83
 * 148.927305(9)
 * 4.20(14) min
 * β+
 * 149Tb
 * 7/2(−)
 * rowspan=2 style="text-indent:1em" | 149mDy
 * rowspan=2 colspan="3" style="text-indent:2em" | 2661.1(4) keV
 * rowspan=2|490(15) ms
 * IT (99.3%)
 * 149Dy
 * rowspan=2|(27/2−)
 * rowspan=2|
 * rowspan=2|
 * β+ (.7%)
 * 149Tb
 * rowspan=2|150Dy
 * rowspan=2 style="text-align:right" | 66
 * rowspan=2 style="text-align:right" | 84
 * rowspan=2|149.925585(5)
 * rowspan=2|7.17(5) min
 * β+ (64%)
 * 150Tb
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * α (36%)
 * 146Gd
 * rowspan=2|151Dy
 * rowspan=2 style="text-align:right" | 66
 * rowspan=2 style="text-align:right" | 85
 * rowspan=2|150.926185(4)
 * rowspan=2|17.9(3) min
 * β+ (94.4%)
 * 151Tb
 * rowspan=2|7/2(−)
 * rowspan=2|
 * rowspan=2|
 * α (5.6%)
 * 147Gd
 * rowspan=2|152Dy
 * rowspan=2 style="text-align:right" | 66
 * rowspan=2 style="text-align:right" | 86
 * rowspan=2|151.924718(6)
 * rowspan=2|2.38(2) h
 * EC (99.9%)
 * 152Tb
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * α (.1%)
 * 148Gd
 * rowspan=2|153Dy
 * rowspan=2 style="text-align:right" | 66
 * rowspan=2 style="text-align:right" | 87
 * rowspan=2|152.925765(5)
 * rowspan=2|6.4(1) h
 * β+ (99.99%)
 * 153Tb
 * rowspan=2|7/2(−)
 * rowspan=2|
 * rowspan=2|
 * α (.00939%)
 * 149Gd
 * 154Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 88
 * 153.924424(8)
 * 1.40(8)×106 y
 * α
 * 150Gd
 * 0+
 * 155Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 89
 * 154.925754(13)
 * 9.9(2) h
 * β+
 * 155Tb
 * 3/2−
 * style="text-indent:1em" | 155mDy
 * colspan="3" style="text-indent:2em" | 234.33(3) keV
 * 6(1) μs
 * 11/2−
 * 156Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 90
 * 155.924283(7)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 5.6(3)×10−4
 * 157Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 91
 * 156.925466(7)
 * 8.14(4) h
 * β+
 * 157Tb
 * 3/2−
 * style="text-indent:1em" | 157m1Dy
 * colspan="3" style="text-indent:2em" | 161.99(3) keV
 * 1.3(2) μs
 * 9/2+
 * style="text-indent:1em" | 157m2Dy
 * colspan="3" style="text-indent:2em" | 199.38(7) keV
 * 21.6(16) ms
 * IT
 * 157Dy
 * 11/2−
 * 158Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 92
 * 157.924409(4)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 9.5(3)×10−4
 * 159Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 93
 * 158.9257392(29)
 * 144.4(2) d
 * EC
 * 159Tb
 * 3/2−
 * style="text-indent:1em" | 159mDy
 * colspan="3" style="text-indent:2em" | 352.77(14) keV
 * 122(3) μs
 * 11/2−
 * 160Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 94
 * 159.9251975(27)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 0.02329(18)
 * 161Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 95
 * 160.9269334(27)
 * colspan=3 align=center|Observationally Stable
 * 5/2+
 * 0.18889(42)
 * 162Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 96
 * 161.9267984(27)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 0.25475(36)
 * 163Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 97
 * 162.9287312(27)
 * colspan=3 align=center|Stable
 * 5/2−
 * 0.24896(42)
 * 164Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 98
 * 163.9291748(27)
 * colspan=3 align=center|Stable
 * 0+
 * 0.28260(54)
 * 165Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 99
 * 164.9317033(27)
 * 2.334(1) h
 * β−
 * 165Ho
 * 7/2+
 * rowspan=2 style="text-indent:1em" | 165mDy
 * rowspan=2 colspan="3" style="text-indent:2em" | 108.160(3) keV
 * rowspan=2|1.257(6) min
 * IT (97.76%)
 * 165Dy
 * rowspan=2|1/2−
 * rowspan=2|
 * rowspan=2|
 * β− (2.24%)
 * 165Ho
 * 166Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 100
 * 165.9328067(28)
 * 81.6(1) h
 * β−
 * 166Ho
 * 0+
 * 167Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 101
 * 166.93566(6)
 * 6.20(8) min
 * β−
 * 167Ho
 * (1/2−)
 * 168Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 102
 * 167.93713(15)
 * 8.7(3) min
 * β−
 * 168Ho
 * 0+
 * 169Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 103
 * 168.94031(32)
 * 39(8) s
 * β−
 * 169Ho
 * (5/2−)
 * 170Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 104
 * 169.94239(21)#
 * 30# s
 * β−
 * 170Ho
 * 0+
 * 171Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 105
 * 170.94620(32)#
 * 6# s
 * β−
 * 171Ho
 * 7/2−#
 * 172Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 106
 * 171.94876(43)#
 * 3# s
 * β−
 * 172Ho
 * 0+
 * 173Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 107
 * 172.95300(54)#
 * 2# s
 * β−
 * 173Ho
 * 9/2+#
 * 5/2+
 * 0.18889(42)
 * 162Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 96
 * 161.9267984(27)
 * colspan=3 align=center|Observationally Stable
 * 0+
 * 0.25475(36)
 * 163Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 97
 * 162.9287312(27)
 * colspan=3 align=center|Stable
 * 5/2−
 * 0.24896(42)
 * 164Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 98
 * 163.9291748(27)
 * colspan=3 align=center|Stable
 * 0+
 * 0.28260(54)
 * 165Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 99
 * 164.9317033(27)
 * 2.334(1) h
 * β−
 * 165Ho
 * 7/2+
 * rowspan=2 style="text-indent:1em" | 165mDy
 * rowspan=2 colspan="3" style="text-indent:2em" | 108.160(3) keV
 * rowspan=2|1.257(6) min
 * IT (97.76%)
 * 165Dy
 * rowspan=2|1/2−
 * rowspan=2|
 * rowspan=2|
 * β− (2.24%)
 * 165Ho
 * 166Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 100
 * 165.9328067(28)
 * 81.6(1) h
 * β−
 * 166Ho
 * 0+
 * 167Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 101
 * 166.93566(6)
 * 6.20(8) min
 * β−
 * 167Ho
 * (1/2−)
 * 168Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 102
 * 167.93713(15)
 * 8.7(3) min
 * β−
 * 168Ho
 * 0+
 * 169Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 103
 * 168.94031(32)
 * 39(8) s
 * β−
 * 169Ho
 * (5/2−)
 * 170Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 104
 * 169.94239(21)#
 * 30# s
 * β−
 * 170Ho
 * 0+
 * 171Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 105
 * 170.94620(32)#
 * 6# s
 * β−
 * 171Ho
 * 7/2−#
 * 172Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 106
 * 171.94876(43)#
 * 3# s
 * β−
 * 172Ho
 * 0+
 * 173Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 107
 * 172.95300(54)#
 * 2# s
 * β−
 * 173Ho
 * 9/2+#
 * 0+
 * 171Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 105
 * 170.94620(32)#
 * 6# s
 * β−
 * 171Ho
 * 7/2−#
 * 172Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 106
 * 171.94876(43)#
 * 3# s
 * β−
 * 172Ho
 * 0+
 * 173Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 107
 * 172.95300(54)#
 * 2# s
 * β−
 * 173Ho
 * 9/2+#
 * 173Dy
 * style="text-align:right" | 66
 * style="text-align:right" | 107
 * 172.95300(54)#
 * 2# s
 * β−
 * 173Ho
 * 9/2+#
 * 9/2+#

 * Geologically exceptional samples are found associated with the Oklo natural nuclear fission reactor, in which the isotopic composition lies outside the reported range. The uncertainty in the atomic mass may exceed the stated value for such specimens.

Dysprosium-165
The radioactive isotope 165Dy, with a half-life of 2.334 hours, has radiopharmaceutical uses in radiation synovectomy of the knee. It had been previously performed with colloidal-sized particles containing longer-lived isotopes such as 198Au and 90Y. The major problem with the usage of those isotopes was radiation leakage out of the knee. 165Dy, with its shorter half-life and thus shorter period of potential radiation leakage, is more suitable for the procedure.

title: Isotopes of dysprosium


text:
Isotopes of terbium

Naturally occurring terbium (65Tb) is composed of one stable isotope, 159Tb. Thirty-seven radioisotopes have been characterized, with the most stable being 158Tb with a half-life of 180 years, 157Tb with a half-life of 71 years, and 160Tb with a half-life of 72.3 days. All of the remaining radioactive isotopes have half-lives that are less than 6.907 days, and the majority of these have half-lives that are less than 24 seconds. This element also has 27 meta states, with the most stable being 156m1Tb (t1/2 = 24.4 hours), 154m2Tb (t1/2 = 22.7 hours) and 154m1Tb (t1/2 = 9.4 hours).

The primary decay mode before the most abundant stable isotope, 159Tb, is electron capture, and the primary mode behind is beta decay. The primary decay products before 159Tb are element Gd (gadolinium) isotopes, and the primary products after 159Tb are element Dy (dysprosium) isotopes.

List of isotopes

 * 135Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 70
 * 0.94(+33−22) ms
 * (7/2−)
 * 136Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 71
 * 135.96138(64)#
 * 0.2# s
 * 137Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 72
 * 136.95598(64)#
 * 600# ms
 * 11/2−#
 * rowspan=2|138Tb
 * rowspan=2 style="text-align:right" | 65
 * rowspan=2 style="text-align:right" | 73
 * rowspan=2|137.95316(43)#
 * rowspan=2|800# ms [>200 ns]
 * β+
 * 138Gd
 * rowspan=2|
 * rowspan=2|
 * p
 * 137Gd
 * 139Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 74
 * 138.94829(32)#
 * 1.6(2) s
 * β+
 * 139Gd
 * 11/2−#
 * rowspan=2|140Tb
 * rowspan=2 style="text-align:right" | 65
 * rowspan=2 style="text-align:right" | 75
 * rowspan=2|139.94581(86)
 * rowspan=2|2.4(2) s
 * β+ (99.74%)
 * 140Gd
 * rowspan=2|5
 * rowspan=2|
 * β+, p (.26%)
 * 139Eu
 * 141Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 76
 * 140.94145(11)
 * 3.5(2) s
 * β+
 * 141Gd
 * (5/2−)
 * style="text-indent:1em" | 141mTb
 * colspan="3" style="text-indent:2em" | 0(200)# keV
 * 7.9(6) s
 * β+
 * 141Gd
 * 11/2−#
 * rowspan=3|142Tb
 * rowspan=3 style="text-align:right" | 65
 * rowspan=3 style="text-align:right" | 77
 * rowspan=3|141.93874(32)#
 * rowspan=3|597(17) ms
 * β+ (96.8(4)%)
 * rowspan=2|142Gd
 * rowspan=3|1+
 * rowspan=3|
 * EC (3.2(4)%)
 * β+, p
 * 141Eu
 * rowspan=2 style="text-indent:1em" | 142m1Tb
 * rowspan=2 colspan="3" style="text-indent:2em" | 280.2(10) keV
 * rowspan=2|303(17) ms
 * IT (99.5%)
 * 142Tb
 * rowspan=2|(5−)
 * rowspan=2|
 * β+ (.5%)
 * 142Gd
 * style="text-indent:1em" | 142m2Tb
 * colspan="3" style="text-indent:2em" | 621.4(11) keV
 * 15(4) μs
 * 143Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 78
 * 142.93512(6)
 * 12(1) s
 * β+
 * 143Gd
 * (11/2−)
 * style="text-indent:1em" | 143mTb
 * colspan="3" style="text-indent:2em" | 0(100)# keV
 * <21 s
 * β+
 * 143Gd
 * 5/2+#
 * rowspan=2|144Tb
 * rowspan=2 style="text-align:right" | 65
 * rowspan=2 style="text-align:right" | 79
 * rowspan=2|143.93305(3)
 * rowspan=2|~1 s
 * β+
 * 144Gd
 * rowspan=2|1+
 * rowspan=2|
 * β+, p (rare)
 * 143Eu
 * rowspan=3 style="text-indent:1em" | 144m1Tb
 * rowspan=3 colspan="3" style="text-indent:2em" | 396.9(5) keV
 * rowspan=3|4.25(15) s
 * IT (66%)
 * 144Tb
 * rowspan=3|(6−)
 * rowspan=3|
 * β+ (34%)
 * 144Gd
 * β+, p (<1%)
 * 143Eu
 * style="text-indent:1em" | 144m2Tb
 * colspan="3" style="text-indent:2em" | 476.2(5) keV
 * 2.8(3) μs
 * (8−)
 * style="text-indent:1em" | 144m3Tb
 * colspan="3" style="text-indent:2em" | 517.1(5) keV
 * 670(60) ns
 * (9+)
 * style="text-indent:1em" | 144m4Tb
 * colspan="3" style="text-indent:2em" | 544.5(6) keV
 * <300 ns
 * (10+)
 * 145Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 80
 * 144.92927(6)
 * 20# min
 * β+
 * 145Gd
 * (3/2+)
 * style="text-indent:1em" | 145mTb
 * colspan="3" style="text-indent:2em" | 0(100)# keV
 * 30.9(7) s
 * β+
 * 145Gd
 * (11/2−)
 * 146Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 81
 * 145.92725(5)
 * 8(4) s
 * β+
 * 146Gd
 * 1+
 * style="text-indent:1em" | 146m1Tb
 * colspan="3" style="text-indent:2em" | 150(100)# keV
 * 24.1(5) s
 * β+
 * 146Gd
 * 5−
 * style="text-indent:1em" | 146m2Tb
 * colspan="3" style="text-indent:2em" | 930(100)# keV
 * 1.18(2) ms
 * (10+)
 * 147Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 82
 * 146.924045(13)
 * 1.64(3) h
 * β+
 * 147Gd
 * 1/2+#
 * style="text-indent:1em" | 147mTb
 * colspan="3" style="text-indent:2em" | 50.6(9) keV
 * 1.87(5) min
 * β+
 * 147Gd
 * (11/2)−
 * 148Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 83
 * 147.924272(15)
 * 60(1) min
 * β+
 * 148Gd
 * 2−
 * style="text-indent:1em" | 148m1Tb
 * colspan="3" style="text-indent:2em" | 90.1(3) keV
 * 2.20(5) min
 * β+
 * 148Gd
 * (9)+
 * style="text-indent:1em" | 148m2Tb
 * colspan="3" style="text-indent:2em" | 8618.6(10) keV
 * 1.310(7) μs
 * (27+)
 * rowspan=2|149Tb
 * rowspan=2 style="text-align:right" | 65
 * rowspan=2 style="text-align:right" | 84
 * rowspan=2|148.923246(5)
 * rowspan=2|4.118(25) h
 * β+ (83.3%)
 * 149Gd
 * rowspan=2|1/2+
 * rowspan=2|
 * α (16.7%)
 * 145Eu
 * rowspan=2 style="text-indent:1em" | 149mTb
 * rowspan=2 colspan="3" style="text-indent:2em" | 35.78(13) keV
 * rowspan=2|4.16(4) min
 * β+ (99.97%)
 * 149Gd
 * rowspan=2|11/2−
 * rowspan=2|
 * α (.022%)
 * 145Eu
 * rowspan=2|150Tb
 * rowspan=2 style="text-align:right" | 65
 * rowspan=2 style="text-align:right" | 85
 * rowspan=2|149.923660(8)
 * rowspan=2|3.48(16) h
 * β+ (99.95%)
 * 150Gd
 * rowspan=2|(2−)
 * rowspan=2|
 * α (.05%)
 * 146Eu
 * rowspan=2 style="text-indent:1em" | 150mTb
 * rowspan=2 colspan="3" style="text-indent:2em" | 457(29) keV
 * rowspan=2|5.8(2) min
 * β+
 * 150Gd
 * rowspan=2|9+
 * rowspan=2|
 * IT (rare)
 * 150Tb
 * rowspan=2|151Tb
 * rowspan=2 style="text-align:right" | 65
 * rowspan=2 style="text-align:right" | 86
 * rowspan=2|150.923103(5)
 * rowspan=2|17.609(1) h
 * β+ (99.99%)
 * 151Gd
 * rowspan=2|1/2(+)
 * rowspan=2|
 * α (.0095%)
 * 147Eu
 * rowspan=2 style="text-indent:1em" | 151mTb
 * rowspan=2 colspan="3" style="text-indent:2em" | 99.54(6) keV
 * rowspan=2|25(3) s
 * IT (93.8%)
 * 151Tb
 * rowspan=2|(11/2−)
 * rowspan=2|
 * β+ (6.2%)
 * 151Gd
 * rowspan=2|152Tb
 * rowspan=2 style="text-align:right" | 65
 * rowspan=2 style="text-align:right" | 87
 * rowspan=2|151.92407(4)
 * rowspan=2|17.8784(95) h
 * β+
 * 152Gd
 * rowspan=2|2−
 * rowspan=2|
 * α (7×10−7%)
 * 148Eu
 * style="text-indent:1em" | 152m1Tb
 * colspan="3" style="text-indent:2em" | 342.15(16) keV
 * 0.96 μs
 * 5−
 * rowspan=2 style="text-indent:1em" | 152m2Tb
 * rowspan=2 colspan="3" style="text-indent:2em" | 501.74(19) keV
 * rowspan=2|4.2(1) min
 * IT (78.8%)
 * 152Tb
 * rowspan=2|8+
 * rowspan=2|
 * β+ (21.2%)
 * 152Gd
 * 153Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 88
 * 152.923435(5)
 * 2.34(1) d
 * β+
 * 153Gd
 * 5/2+
 * style="text-indent:1em" | 153mTb
 * colspan="3" style="text-indent:2em" | 163.175(5) keV
 * 186(4) μs
 * 11/2−
 * rowspan=2|154Tb
 * rowspan=2 style="text-align:right" | 65
 * rowspan=2 style="text-align:right" | 89
 * rowspan=2|153.92468(5)
 * rowspan=2|21.5(4) h
 * β+ (99.9%)
 * 154Gd
 * rowspan=2|0(+#)
 * rowspan=2|
 * β− (.1%)
 * 154Dy
 * rowspan=3 style="text-indent:1em" | 154m1Tb
 * rowspan=3 colspan="3" style="text-indent:2em" | 12(7) keV
 * rowspan=3|9.4(4) h
 * β+ (78.2%)
 * 154Gd
 * rowspan=3|3−
 * rowspan=3|
 * IT (21.8%)
 * 154Tb
 * β− (.1%)
 * 154Dy
 * style="text-indent:1em" | 154m2Tb
 * colspan="3" style="text-indent:2em" | 200(150)# keV
 * 22.7(5) h
 * 7−
 * style="text-indent:1em" | 154m3Tb
 * colspan="3" style="text-indent:2em" | 0+Z keV
 * 513(42) ns
 * 155Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 90
 * 154.923505(13)
 * 5.32(6) d
 * EC
 * 155Gd
 * 3/2+
 * rowspan=2|156Tb
 * rowspan=2 style="text-align:right" | 65
 * rowspan=2 style="text-align:right" | 91
 * rowspan=2|155.924747(5)
 * rowspan=2|5.35(10) d
 * β+
 * 156Gd
 * rowspan=2|3−
 * rowspan=2|
 * β− (rare)
 * 156Dy
 * style="text-indent:1em" | 156m1Tb
 * colspan="3" style="text-indent:2em" | 54(3) keV
 * 24.4(10) h
 * IT
 * 156Tb
 * (7−)
 * style="text-indent:1em" | 156m2Tb
 * colspan="3" style="text-indent:2em" | 88.4(2) keV
 * 5.3(2) h
 * (0+)
 * 157Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 92
 * 156.9240246(27)
 * 71(7) y
 * EC
 * 157Gd
 * 3/2+
 * rowspan=2|158Tb
 * rowspan=2 style="text-align:right" | 65
 * rowspan=2 style="text-align:right" | 93
 * rowspan=2|157.9254131(28)
 * rowspan=2|180(11) y
 * β+ (83.4%)
 * 158Gd
 * rowspan=2|3−
 * rowspan=2|
 * β− (16.6%)
 * 158Dy
 * rowspan=3 style="text-indent:1em" | 158m1Tb
 * rowspan=3 colspan="3" style="text-indent:2em" | 110.3(12) keV
 * rowspan=3|10.70(17) s
 * IT (99.39%)
 * 158Tb
 * rowspan=3|0−
 * rowspan=3|
 * β− (.6%)
 * 158Dy
 * β+ (.01%)
 * 158Gd
 * style="text-indent:1em" | 158m2Tb
 * colspan="3" style="text-indent:2em" | 388.37(15) keV
 * 0.40(4) ms
 * 7−
 * 159Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 94
 * 158.9253468(27)
 * colspan=3 align=center|Stable
 * 3/2+
 * 1.0000
 * 160Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 95
 * 159.9271676(27)
 * 72.3(2) d
 * β−
 * 160Dy
 * 3−
 * 161Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 96
 * 160.9275699(28)
 * 6.906(19) d
 * β−
 * 161Dy
 * 3/2+
 * 162Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 97
 * 161.92949(4)
 * 7.60(15) min
 * β−
 * 162Dy
 * 1−
 * 163Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 98
 * 162.930648(5)
 * 19.5(3) min
 * β−
 * 163Dy
 * 3/2+
 * 164Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 99
 * 163.93335(11)
 * 3.0(1) min
 * β−
 * 164Dy
 * (5+)
 * 165Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 100
 * 164.93488(21)#
 * 2.11(10) min
 * β−
 * 165mDy
 * 3/2+#
 * 166Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 101
 * 165.93799(11)
 * 25.6(22) s
 * β−
 * 166Dy
 * 167Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 102
 * 166.94005(43)#
 * 19.4(27) s
 * β−
 * 167Dy
 * 3/2+#
 * 168Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 103
 * 167.94364(54)#
 * 8.2(13) s
 * β−
 * 168Dy
 * 4−#
 * 169Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 104
 * 168.94622(64)#
 * 5.13(32) s
 * β−
 * 169Dy
 * 3/2+#
 * 170Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 105
 * 169.95025(75)#
 * 960(78) ms
 * β−
 * 170Dy
 * 171Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 106
 * 170.95330(86)#
 * 1.23(10) s
 * β−
 * 171Dy
 * 3/2+#
 * 172Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 107
 * 760(190) ms
 * β−
 * 172Dy
 * 6+#
 * rowspan=2 style="text-align:right" | 93
 * rowspan=2|157.9254131(28)
 * rowspan=2|180(11) y
 * β+ (83.4%)
 * 158Gd
 * rowspan=2|3−
 * rowspan=2|
 * β− (16.6%)
 * 158Dy
 * rowspan=3 style="text-indent:1em" | 158m1Tb
 * rowspan=3 colspan="3" style="text-indent:2em" | 110.3(12) keV
 * rowspan=3|10.70(17) s
 * IT (99.39%)
 * 158Tb
 * rowspan=3|0−
 * rowspan=3|
 * β− (.6%)
 * 158Dy
 * β+ (.01%)
 * 158Gd
 * style="text-indent:1em" | 158m2Tb
 * colspan="3" style="text-indent:2em" | 388.37(15) keV
 * 0.40(4) ms
 * 7−
 * 159Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 94
 * 158.9253468(27)
 * colspan=3 align=center|Stable
 * 3/2+
 * 1.0000
 * 160Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 95
 * 159.9271676(27)
 * 72.3(2) d
 * β−
 * 160Dy
 * 3−
 * 161Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 96
 * 160.9275699(28)
 * 6.906(19) d
 * β−
 * 161Dy
 * 3/2+
 * 162Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 97
 * 161.92949(4)
 * 7.60(15) min
 * β−
 * 162Dy
 * 1−
 * 163Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 98
 * 162.930648(5)
 * 19.5(3) min
 * β−
 * 163Dy
 * 3/2+
 * 164Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 99
 * 163.93335(11)
 * 3.0(1) min
 * β−
 * 164Dy
 * (5+)
 * 165Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 100
 * 164.93488(21)#
 * 2.11(10) min
 * β−
 * 165mDy
 * 3/2+#
 * 166Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 101
 * 165.93799(11)
 * 25.6(22) s
 * β−
 * 166Dy
 * 167Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 102
 * 166.94005(43)#
 * 19.4(27) s
 * β−
 * 167Dy
 * 3/2+#
 * 168Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 103
 * 167.94364(54)#
 * 8.2(13) s
 * β−
 * 168Dy
 * 4−#
 * 169Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 104
 * 168.94622(64)#
 * 5.13(32) s
 * β−
 * 169Dy
 * 3/2+#
 * 170Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 105
 * 169.95025(75)#
 * 960(78) ms
 * β−
 * 170Dy
 * 171Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 106
 * 170.95330(86)#
 * 1.23(10) s
 * β−
 * 171Dy
 * 3/2+#
 * 172Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 107
 * 760(190) ms
 * β−
 * 172Dy
 * 6+#
 * style="text-align:right" | 65
 * style="text-align:right" | 104
 * 168.94622(64)#
 * 5.13(32) s
 * β−
 * 169Dy
 * 3/2+#
 * 170Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 105
 * 169.95025(75)#
 * 960(78) ms
 * β−
 * 170Dy
 * 171Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 106
 * 170.95330(86)#
 * 1.23(10) s
 * β−
 * 171Dy
 * 3/2+#
 * 172Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 107
 * 760(190) ms
 * β−
 * 172Dy
 * 6+#
 * 172Tb
 * style="text-align:right" | 65
 * style="text-align:right" | 107
 * 760(190) ms
 * β−
 * 172Dy
 * 6+#
 * 6+#

title: Isotopes of terbium


text:
Isotopes of gadolinium

Naturally occurring gadolinium (64Gd) is composed of 6 stable isotopes, 154Gd, 155Gd, 156Gd, 157Gd, 158Gd and 160Gd, and 1 radioisotope, 152Gd, with 158Gd being the most abundant (24.84% natural abundance). The predicted double beta decay of 160Gd has never been observed; only a lower limit on its half-life of more than 1.3×1021 years has been set experimentally.

Thirty-three radioisotopes have been characterized, with the most stable being alpha-decaying 152Gd (naturally occurring) with a half-life of 1.08×1014 years, and 150Gd with a half-life of 1.79×106 years. All of the remaining radioactive isotopes have half-lives less than 100 years, the majority of these having half-lives less than 24.6 seconds. Gadolinium isotopes have 10 metastable isomers, with the most stable being 143mGd (t1/2 = 110 seconds), 145mGd (t1/2 = 85 seconds) and 141mGd (t1/2 = 24.5 seconds).

The primary decay mode at atomic weights lower than the most abundant stable isotope, 158Gd, is electron capture, and the primary mode at higher atomic weights is beta decay. The primary decay products for isotopes lighter than 158Gd are isotopes of europium and the primary products of heavier isotopes are isotopes of terbium.

List of isotopes

 * rowspan=2|135Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 71
 * rowspan=2|134.95250(43)#
 * rowspan=2|1.1(2) s
 * β+ (98%)
 * 135Eu
 * rowspan=2|(5/2+)
 * rowspan=2|
 * rowspan=2|
 * β+, p (98%)
 * 134Sm
 * rowspan=2|136Gd
 * rowspan=2 tyle="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 72
 * rowspan=2|135.94730(32)#
 * rowspan=2|1# s [>200 ns]
 * β+?
 * 136Eu
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β+, p?
 * 135Sm
 * rowspan=2|137Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 73
 * rowspan=2|136.94502(32)#
 * rowspan=2|2.2(2) s
 * β+
 * 137Eu
 * rowspan=2|(7/2)+#
 * rowspan=2|
 * rowspan=2|
 * β+, p?
 * 136Sm
 * 138Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 74
 * 137.94025(22)#
 * 4.7(9) s
 * β+
 * 138Eu
 * 0+
 * style="text-indent:1em" | 138mGd
 * colspan="3" style="text-indent:2em" | 2232.6(11) keV
 * 6.2(0.2) μs
 * IT
 * 138Gd
 * (8−)
 * rowspan=2|139Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 75
 * rowspan=2|138.93813(21)#
 * rowspan=2|5.7(3) s
 * β+
 * 139Eu
 * rowspan=2|9/2−#
 * rowspan=2|
 * rowspan=2|
 * β+, p?
 * 138Sm
 * rowspan=2 style="text-indent:1em" | 139mGd
 * rowspan=2 colspan="3" style="text-indent:2em" | 250(150)# keV
 * rowspan=2|4.8(9) s
 * β+
 * 139Eu
 * rowspan=2|1/2+#
 * rowspan=2|
 * rowspan=2|
 * β+, p?
 * 138Sm
 * rowspan=2|140Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 76
 * rowspan=2|139.933674(30)
 * rowspan=2|15.8(4) s
 * β+ (67(8)%)
 * rowspan=2|140Eu
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * EC (33(8)%)
 * rowspan=2|141Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 77
 * rowspan=2|140.932126(21)
 * rowspan=2|14(4) s
 * β+ (99.97%)
 * 141Eu
 * rowspan=2|(1/2+)
 * rowspan=2|
 * rowspan=2|
 * β+, p (0.03%)
 * 140Sm
 * rowspan=2 style="text-indent:1em" | 141mGd
 * rowspan=2 colspan="3" style="text-indent:2em" | 377.76(9) keV
 * rowspan=2|24.5(5) s
 * β+ (89%)
 * 141Eu
 * rowspan=2|(11/2−)
 * rowspan=2|
 * rowspan=2|
 * IT (11%)
 * 141Gd
 * rowspan=2|142Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 78
 * rowspan=2|141.928116(30)
 * rowspan=2|70.2(6) s
 * EC (52(5)%)
 * rowspan=2|142Eu
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β+ (48(5)%)
 * rowspan=3|143Gd
 * rowspan=3 style="text-align:right" | 64
 * rowspan=3 style="text-align:right" | 79
 * rowspan=3|142.92675(22)
 * rowspan=3|39(2) s
 * β+
 * 143Eu
 * rowspan=3|1/2+
 * rowspan=3|
 * rowspan=3|
 * β+, p?
 * 142Sm
 * β+, α?
 * 139Pm
 * rowspan=3 style="text-indent:1em" | 143mGd
 * rowspan=3 colspan="3" style="text-indent:2em" | 152.6(5) keV
 * rowspan=3|110.0(14) s
 * β+
 * 143Eu
 * rowspan=3|11/2−
 * rowspan=3|
 * rowspan=3|
 * β+, p?
 * 142Sm
 * β+, α?
 * 139Pm
 * 144Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 80
 * 143.922963(30)
 * 4.47(6) min
 * β+
 * 144Eu
 * 0+
 * style="text-indent:1em" | 144mGd
 * colspan="3" style="text-indent:2em" | 3433.1(5) keV
 * 145(30) ns
 * IT
 * 144Gd
 * (10+)
 * 145Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 81
 * 144.921710(21)
 * 23.0(4) min
 * β+
 * 145Eu
 * 1/2+
 * rowspan=2 style="text-indent:1em" | 145mGd
 * rowspan=2 colspan="3" style="text-indent:2em" | 749.1(2) keV
 * rowspan=2|85(3) s
 * IT (94.3%)
 * 145Gd
 * rowspan=2|11/2−
 * rowspan=2|
 * rowspan=2|
 * β+ (5.7%)
 * 145Eu
 * 146Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 82
 * 145.9183185(44)
 * 48.27(10) d
 * EC
 * 146Eu
 * 0+
 * 147Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 83
 * 146.9191010(20)
 * 38.06(12) h
 * β+
 * 147Eu
 * 7/2−
 * style="text-indent:1em" | 147mGd
 * colspan="3" style="text-indent:2em" | 8587.8(5) keV
 * 510(20) ns
 * IT
 * 147Gd
 * 49/2+
 * 148Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 84
 * 147.9181214(16)
 * 86.9(39) y
 * α
 * 144Sm
 * 0+
 * rowspan=2|149Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 85
 * rowspan=2|148.9193477(36)
 * rowspan=2|9.28(10) d
 * β+
 * 149Eu
 * rowspan=2|7/2−
 * rowspan=2|
 * rowspan=2|
 * α (4.3×10−4%)
 * 145Sm
 * 150Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 86
 * 149.9186639(65)
 * 1.79(8)×106 y
 * α
 * 146Sm
 * 0+
 * rowspan=2|151Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 87
 * rowspan=2|150.9203549(32)
 * rowspan=2|123.9(10) d
 * EC
 * 151Eu
 * rowspan=2|7/2−
 * rowspan=2|
 * rowspan=2|
 * α (1.1×10−6%)
 * 147Sm
 * 152Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 88
 * 151.9197984(11)
 * 1.08(8)×1014 y
 * α
 * 148Sm
 * 0+
 * 0.0020(1)
 * 153Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 89
 * 152.9217569(11)
 * 240.6(7) d
 * EC
 * 153Eu
 * 3/2−
 * style="text-indent:1em" | 153m1Gd
 * colspan="3" style="text-indent:2em" | 95.1737(8) keV
 * 3.5(4) μs
 * IT
 * 153Gd
 * 9/2+
 * style="text-indent:1em" | 153m2Gd
 * colspan="3" style="text-indent:2em" | 171.188(4) keV
 * 76.0(14) μs
 * IT
 * 153Gd
 * (11/2−)
 * 154Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 90
 * 153.9208730(11)
 * colspan="3" style="text-align:center;"|Observationally Stable
 * 0+
 * 0.0218(2)
 * 155Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 91
 * 154.9226294(11)
 * colspan="3" style="text-align:center;"|Observationally Stable
 * 3/2−
 * 0.1480(9)
 * style="text-indent:1em" | 155mGd
 * colspan="3" style="text-indent:2em" | 121.10(19) keV
 * 31.97(27) ms
 * IT
 * 155Gd
 * 11/2−
 * 156Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 92
 * 155.9221301(11)
 * colspan="3" style="text-align:center;"|Stable
 * 0+
 * 0.2047(3)
 * style="text-indent:1em" | 156mGd
 * colspan="3" style="text-indent:2em" | 2137.60(5) keV
 * 1.3(1) μs
 * IT
 * 156Gd
 * 7-
 * 157Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 93
 * 156.9239674(10)
 * colspan="3" style="text-align:center;"|Stable
 * 3/2−
 * 0.1565(4)
 * style="text-indent:1em" | 157m1Gd
 * colspan="3" style="text-indent:2em" | 63.916(5) keV
 * 460(40) ns
 * IT
 * 157Gd
 * 5/2+
 * style="text-indent:1em" | 157m2Gd
 * colspan="3" style="text-indent:2em" | 426.539(23) keV
 * 18.5(23) μs
 * IT
 * 157Gd
 * 11/2−
 * 158Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 94
 * 157.9241112(10)
 * colspan="3" style="text-align:center;"|Stable
 * 0+
 * 0.2484(8)
 * 159Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 95
 * 158.9263958(11)
 * 18.479(4) h
 * β−
 * 159Tb
 * 3/2−
 * 160Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 96
 * 159.9270612(12)
 * colspan="3" style="text-align:center;"|Observationally Stable
 * 0+
 * 0.2186(3)
 * 161Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 97
 * 160.9296763(16)
 * 3.646(3) min
 * β−
 * 161Tb
 * 5/2−
 * 162Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 98
 * 161.9309918(43)
 * 8.4(2) min
 * β−
 * 162Tb
 * 0+
 * 163Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 99
 * 162.93409664(86)
 * 68(3) s
 * β−
 * 163Tb
 * 7/2+
 * rowspan=2 style="text-indent:1em" | 163mGd
 * rowspan=2 colspan="3" style="text-indent:2em" | 138.22(20) keV
 * rowspan=2|23.5(10) s
 * IT?
 * 163Gd
 * rowspan=2|1/2−
 * rowspan=2|
 * rowspan=2|
 * β−
 * 163Tb
 * 164Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 100
 * 163.9359162(11)
 * 45(3) s
 * β−
 * 164Tb
 * 0+
 * style="text-indent:1em" | 164mGd
 * colspan="3" style="text-indent:2em" | 1095.8(4) keV
 * 589(18) ns
 * IT
 * 164Gd
 * (4−)
 * 165Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 101
 * 164.9393171(14)
 * 11.6(10) s
 * β−
 * 165Tb
 * 1/2−#
 * 166Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 102
 * 165.9416304(17)
 * 5.1(8) s
 * β−
 * 166Tb
 * 0+
 * style="text-indent:1em" | 166mGd
 * colspan="3" style="text-indent:2em" | 1601.5(11) keV
 * 950(60) ns
 * IT
 * 166Gd
 * (6−)
 * 167Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 103
 * 166.9454900(56)
 * 4.2(3) s
 * β−
 * 167Tb
 * 5/2−#
 * 168Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 104
 * 167.94831(32)#
 * 3.03(16) s
 * β−
 * 168Tb
 * 0+
 * rowspan=2|169Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 105
 * rowspan=2|168.95288(43)#
 * rowspan=2|750(210) ms
 * β−
 * 169Tb
 * rowspan=2|7/2−#
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<0.7%)
 * 168Tb
 * rowspan=2|170Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 106
 * rowspan=2|169.95615(54)#
 * rowspan=2|$675 ms$
 * β−
 * 170Tb
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<3%)
 * 169Tb
 * rowspan=2|171Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 107
 * rowspan=2|170.96113(54)#
 * rowspan=2|$392 ms$
 * β−
 * 171Tb
 * rowspan=2|9/2+#
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<10%)
 * 170Tb
 * rowspan=2|172Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 108
 * rowspan=2|171.96461(32)#
 * rowspan=2|$163 ms$
 * β−
 * 172Tb
 * rowspan=2|0+#
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<50%)
 * 171Tb
 * IT?
 * 163Gd
 * rowspan=2|1/2−
 * rowspan=2|
 * rowspan=2|
 * β−
 * 163Tb
 * 164Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 100
 * 163.9359162(11)
 * 45(3) s
 * β−
 * 164Tb
 * 0+
 * style="text-indent:1em" | 164mGd
 * colspan="3" style="text-indent:2em" | 1095.8(4) keV
 * 589(18) ns
 * IT
 * 164Gd
 * (4−)
 * 165Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 101
 * 164.9393171(14)
 * 11.6(10) s
 * β−
 * 165Tb
 * 1/2−#
 * 166Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 102
 * 165.9416304(17)
 * 5.1(8) s
 * β−
 * 166Tb
 * 0+
 * style="text-indent:1em" | 166mGd
 * colspan="3" style="text-indent:2em" | 1601.5(11) keV
 * 950(60) ns
 * IT
 * 166Gd
 * (6−)
 * 167Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 103
 * 166.9454900(56)
 * 4.2(3) s
 * β−
 * 167Tb
 * 5/2−#
 * 168Gd
 * style="text-align:right" | 64
 * style="text-align:right" | 104
 * 167.94831(32)#
 * 3.03(16) s
 * β−
 * 168Tb
 * 0+
 * rowspan=2|169Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 105
 * rowspan=2|168.95288(43)#
 * rowspan=2|750(210) ms
 * β−
 * 169Tb
 * rowspan=2|7/2−#
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<0.7%)
 * 168Tb
 * rowspan=2|170Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 106
 * rowspan=2|169.95615(54)#
 * rowspan=2|$86.9 year$
 * β−
 * 170Tb
 * rowspan=2|0+
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<3%)
 * 169Tb
 * rowspan=2|171Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 107
 * rowspan=2|170.96113(54)#
 * rowspan=2|$240.4 day$
 * β−
 * 171Tb
 * rowspan=2|9/2+#
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<10%)
 * 170Tb
 * rowspan=2|172Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 108
 * rowspan=2|171.96461(32)#
 * rowspan=2|⇭⇭⇭
 * β−
 * 172Tb
 * rowspan=2|0+#
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<50%)
 * 171Tb
 * β−, n? (<3%)
 * 169Tb
 * rowspan=2|171Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 107
 * rowspan=2|170.96113(54)#
 * rowspan=2|⇭⇭⇭
 * β−
 * 171Tb
 * rowspan=2|9/2+#
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<10%)
 * 170Tb
 * rowspan=2|172Gd
 * rowspan=2 style="text-align:right" | 64
 * rowspan=2 style="text-align:right" | 108
 * rowspan=2|171.96461(32)#
 * rowspan=2|⇭⇭⇭
 * β−
 * 172Tb
 * rowspan=2|0+#
 * rowspan=2|
 * rowspan=2|
 * β−, n? (<50%)
 * 171Tb
 * rowspan=2|
 * β−, n? (<50%)
 * 171Tb
 * 171Tb

Gadolinium-148
With a half-life of ⇭⇭⇭ via alpha decay alone, gadolinium-148 would be ideal for radioisotope thermoelectric generators. However, gadolinium-148 cannot be economically synthesized in sufficient quantities to power a RTG.

Gadolinium-153
Gadolinium-153 has a half-life of ⇭⇭⇭ and emits gamma radiation with strong peaks at 41 keV and 102 keV. It is used as a gamma ray source for X-ray absorptiometry and fluorescence, for bone density gauges for osteoporosis screening, and for radiometric profiling in the Lixiscope portable x-ray imaging system, also known as the Lixi Profiler. In nuclear medicine, it serves to calibrate the equipment needed like single-photon emission computed tomography systems (SPECT) to make x-rays. It ensures that the machines work correctly to produce images of radioisotope distribution inside the patient. This isotope is produced in a nuclear reactor from europium or enriched gadolinium. It can also detect the loss of calcium in the hip and back bones, allowing the ability to diagnose osteoporosis.

title: Isotopes of gadolinium


text:
Isotopes of europium

Naturally occurring europium (63Eu) is composed of two isotopes, 151Eu and 153Eu, with 153Eu being the most abundant (52.2% natural abundance). While 153Eu is observationally stable (theoretically can undergo alpha decay with half-life over 5.5×1017 years), 151Eu was found in 2007 to be unstable and undergo alpha decay. The half-life is measured to be (4.62 ± 0.95(stat.) ± 0.68(syst.)) × 1018 years which corresponds to 1 alpha decay per two minutes in every kilogram of natural europium. Besides the natural radioisotope 151Eu, 36 artificial radioisotopes have been characterized, with the most stable being 150Eu with a half-life of 36.9 years, 152Eu with a half-life of 13.516 years, 154Eu with a half-life of 8.593 years, and 155Eu with a half-life of 4.7612 years. The majority of the remaining radioactive isotopes, which range from 130Eu to 170Eu, have half-lives that are less than 12.2 seconds. This element also has 18 metastable isomers, with the most stable being 150mEu (t1/2 12.8 hours), 152m1Eu (t1/2 9.3116 hours) and 152m5Eu (t1/2 96 minutes). The primary decay mode before the most abundant stable isotope, 153Eu, is electron capture, and the primary mode after is beta decay. The primary decay products before 153Eu are isotopes of samarium and the primary products after are isotopes of gadolinium.

List of isotopes

 * 130Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 67
 * 129.96357(54)#
 * 1.1(5) ms [0.9(+5−3) ms]
 * 2+#
 * 131Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 68
 * 130.95775(43)#
 * 17.8(19) ms
 * 3/2+
 * rowspan=2|132Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 69
 * rowspan=2|131.95437(43)#
 * rowspan=2|100# ms
 * β+
 * 132Sm
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * p
 * 131Sm
 * 133Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 70
 * 132.94924(32)#
 * 200# ms
 * β+
 * 133Sm
 * 11/2−#
 * rowspan=2|134Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 71
 * rowspan=2|133.94651(21)#
 * rowspan=2|0.5(2) s
 * β+
 * 134Sm
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β+, p (rare)
 * 133Pm
 * rowspan=2|135Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 72
 * rowspan=2|134.94182(32)#
 * rowspan=2|1.5(2) s
 * β+
 * 135Sm
 * rowspan=2|11/2−#
 * rowspan=2|
 * rowspan=2|
 * β+, p
 * 134Pm
 * rowspan=2|136Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 73
 * rowspan=2|135.93960(21)#
 * rowspan=2|3.3(3) s
 * β+ (99.91%)
 * 136Sm
 * rowspan=2|(7+)
 * rowspan=2|
 * rowspan=2|
 * β+, p (.09%)
 * 135Pm
 * rowspan=2 style="text-indent:1em" | 136mEu
 * rowspan=2 colspan="3" style="text-indent:2em" | 0(500)# keV
 * rowspan=2|3.8(3) s
 * β+ (99.91%)
 * 136Sm
 * rowspan=2|(3+)
 * rowspan=2|
 * rowspan=2|
 * β+, p (.09%)
 * 135Pm
 * 137Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 74
 * 136.93557(21)#
 * 8.4(5) s
 * β+
 * 137Sm
 * 11/2−#
 * 138Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 75
 * 137.93371(3)
 * 12.1(6) s
 * β+
 * 138Sm
 * (6−)
 * 139Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 76
 * 138.929792(14)
 * 17.9(6) s
 * β+
 * 139Sm
 * (11/2)−
 * rowspan=2|140Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 77
 * rowspan=2|139.92809(6)
 * rowspan=2|1.51(2) s
 * β+ (95.1(7)%)
 * rowspan=2|140Sm
 * rowspan=2|1+
 * rowspan=2|
 * rowspan=2|
 * EC (4.9(7)%)
 * rowspan=2 style="text-indent:1em" | 140mEu
 * rowspan=2 colspan="3" style="text-indent:2em" | 210(15) keV
 * rowspan=2|125(2) ms
 * IT (99%)
 * 140Eu
 * rowspan=2|5−#
 * rowspan=2|
 * rowspan=2|
 * β+(1%)
 * 140Sm
 * 141Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 78
 * 140.924931(14)
 * 40.7(7) s
 * β+
 * 141Sm
 * 5/2+
 * rowspan=2 style="text-indent:1em" | 141mEu
 * rowspan=2 colspan="3" style="text-indent:2em" | 96.45(7) keV
 * rowspan=2|2.7(3) s
 * IT (86%)
 * 141Eu
 * rowspan=2|11/2−
 * rowspan=2|
 * rowspan=2|
 * β+ (14%)
 * 141Sm
 * rowspan=2|142Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 79
 * rowspan=2|141.92343(3)
 * rowspan=2|2.36(10) s
 * β+ (89.9(16)%)
 * rowspan=2|142Sm
 * rowspan=2|1+
 * rowspan=2|
 * rowspan=2|
 * EC (11.1(16)%)
 * style="text-indent:1em" | 142mEu
 * colspan="3" style="text-indent:2em" | 460(30) keV
 * 1.223(8) min
 * β+
 * 142Sm
 * 8−
 * 143Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 80
 * 142.920298(12)
 * 2.59(2) min
 * β+
 * 143Sm
 * 5/2+
 * style="text-indent:1em" | 143mEu
 * colspan="3" style="text-indent:2em" | 389.51(4) keV
 * 50.0(5) μs
 * 11/2−
 * 144Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 81
 * 143.918817(12)
 * 10.2(1) s
 * β+
 * 144Sm
 * 1+
 * style="text-indent:1em" | 144mEu
 * colspan="3" style="text-indent:2em" | 1127.6(6) keV
 * 1.0(1) μs
 * (8−)
 * 145Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 82
 * 144.916265(4)
 * 5.93(4) d
 * β+
 * 145Sm
 * 5/2+
 * style="text-indent:1em" | 145mEu
 * colspan="3" style="text-indent:2em" | 716.0(3) keV
 * 490 ns
 * 11/2−
 * 146Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 83
 * 145.917206(7)
 * 4.61(3) d
 * β+
 * 146Sm
 * 4−
 * style="text-indent:1em" | 146mEu
 * colspan="3" style="text-indent:2em" | 666.37(16) keV
 * 235(3) μs
 * 9+
 * rowspan=2|147Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 84
 * rowspan=2|146.916746(3)
 * rowspan=2|24.1(6) d
 * β+ (99.99%)
 * 147Sm
 * rowspan=2|5/2+
 * rowspan=2|
 * rowspan=2|
 * α (.0022%)
 * 143Pm
 * rowspan=2|148Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 85
 * rowspan=2|147.918086(11)
 * rowspan=2|54.5(5) d
 * β+ (100%)
 * 148Sm
 * rowspan=2|5−
 * rowspan=2|
 * rowspan=2|
 * α (9.39×10−7%)
 * 144Pm
 * 149Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 86
 * 148.917931(5)
 * 93.1(4) d
 * EC
 * 149Sm
 * 5/2+
 * 150Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 87
 * 149.919702(7)
 * 36.9(9) y
 * β+
 * 150Sm
 * 5(−)
 * rowspan=3 style="text-indent:1em" | 150mEu
 * rowspan=3 colspan="3" style="text-indent:2em" | 42.1(5) keV
 * rowspan=3|12.8(1) h
 * β− (89%)
 * 150Gd
 * rowspan=3|0−
 * rowspan=3|
 * rowspan=3|
 * β+ (11%)
 * 150Sm
 * IT (5×10−8%)
 * 150Eu
 * 151Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 88
 * 150.9198502(26)
 * 4.62×1018 y
 * α
 * 147Pm
 * 5/2+
 * 0.4781(6)
 * style="text-indent:1em" | 151mEu
 * colspan="3" style="text-indent:2em" | 196.245(10) keV
 * 58.9(5) μs
 * 11/2−
 * rowspan=3|152Eu
 * rowspan=3 style="text-align:right" | 63
 * rowspan=3 style="text-align:right" | 89
 * rowspan=3|151.9217445(26)
 * rowspan=3|13.537(6) y
 * EC (72.09%)
 * 152Sm
 * rowspan=3|3−
 * rowspan=3|
 * rowspan=3|
 * β− (27.9%)
 * 152Gd
 * β+ (0.027%)
 * 152Sm
 * rowspan=2 style="text-indent:1em" | 152m1Eu
 * rowspan=2 colspan="3" style="text-indent:2em" | 45.5998(4) keV
 * rowspan=2|9.3116(13) h
 * β− (72%)
 * 152Gd
 * rowspan=2|0−
 * rowspan=2|
 * rowspan=2|
 * β+ (28%)
 * 152Sm
 * style="text-indent:1em" | 152m2Eu
 * colspan="3" style="text-indent:2em" | 65.2969(4) keV
 * 0.94(8) μs
 * 1−
 * style="text-indent:1em" | 152m3Eu
 * colspan="3" style="text-indent:2em" | 78.2331(4) keV
 * 165(10) ns
 * 1+
 * style="text-indent:1em" | 152m4Eu
 * colspan="3" style="text-indent:2em" | 89.8496(4) keV
 * 384(10) ns
 * 4+
 * style="text-indent:1em" | 152m5Eu
 * colspan="3" style="text-indent:2em" | 147.86(10) keV
 * 96(1) min
 * 8−
 * 153Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 90
 * 152.9212303(26)
 * colspan=3 align=center|Observationally Stable
 * 5/2+
 * 0.5219(6)
 * rowspan=2|154Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 91
 * rowspan=2|153.9229792(26)
 * rowspan=2|8.593(4) y
 * β− (99.98%)
 * 154Gd
 * rowspan=2|3−
 * rowspan=2|
 * rowspan=2|
 * EC (.02%)
 * 154Sm
 * style="text-indent:1em" | 154m1Eu
 * colspan="3" style="text-indent:2em" | 68.1702(4) keV
 * 2.2(1) μs
 * IT
 * 154Eu
 * 2+
 * style="text-indent:1em" | 154m2Eu
 * colspan="3" style="text-indent:2em" | 145.3(3) keV
 * 46.3(4) min
 * IT
 * 154Eu
 * (8−)
 * 155Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 92
 * 154.9228933(27)
 * 4.7611(13) y
 * β−
 * 155Gd
 * 5/2+
 * 156Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 93
 * 155.924752(6)
 * 15.19(8) d
 * β−
 * 156Gd
 * 0+
 * 157Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 94
 * 156.925424(6)
 * 15.18(3) h
 * β−
 * 157Gd
 * 5/2+
 * 158Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 95
 * 157.92785(8)
 * 45.9(2) min
 * β−
 * 158Gd
 * (1−)
 * 159Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 96
 * 158.929089(8)
 * 18.1(1) min
 * β−
 * 159Gd
 * 5/2+
 * 160Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 97
 * 159.93197(22)#
 * 38(4) s
 * β−
 * 160Gd
 * 1(−)
 * 161Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 98
 * 160.93368(32)#
 * 26(3) s
 * β−
 * 161Gd
 * 5/2+#
 * 162Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 99
 * 161.93704(32)#
 * 10.6(10) s
 * β−
 * 162Gd
 * 163Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 100
 * 162.93921(54)#
 * 7.7(4) s
 * β−
 * 163Gd
 * 5/2+#
 * style="text-indent:1em" | 163mEu
 * colspan="3" style="text-indent:2em" | 964.5(10) keV
 * 911(24) ns
 * (13/2−)
 * 164Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 101
 * 163.94299(64)#
 * 4.16(19) s
 * β−
 * 164Gd
 * 165Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 102
 * 164.94572(75)#
 * β−
 * 165Gd
 * 5/2+#
 * rowspan=2|166Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 103
 * rowspan=2|165.94997(86)#
 * rowspan=2|$5.5 years$
 * β− (99.37%)
 * 166Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n (0.63%)
 * 165Gd
 * rowspan=2|167Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 104
 * rowspan=2|166.95321(86)#
 * rowspan=2|$2.163 s$
 * β− (98.05%)
 * 167Gd
 * rowspan=2|5/2+#
 * rowspan=2|
 * rowspan=2|
 * β−, n (1.95%)
 * 166Gd
 * rowspan=2|168Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 105
 * rowspan=2|
 * rowspan=2|$1.277 s$
 * β− (96.05%)
 * 168Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n (3.95%)
 * 167Gd
 * rowspan=2|169Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 106
 * rowspan=2|
 * rowspan=2|$852 s$
 * β− (85.38%)
 * 169Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n (14.62%)
 * 168Gd
 * rowspan=2|170Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 107
 * rowspan=2|
 * rowspan=2|$440 s$
 * β−
 * 170Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 169Gd
 * 155.924752(6)
 * 15.19(8) d
 * β−
 * 156Gd
 * 0+
 * 157Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 94
 * 156.925424(6)
 * 15.18(3) h
 * β−
 * 157Gd
 * 5/2+
 * 158Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 95
 * 157.92785(8)
 * 45.9(2) min
 * β−
 * 158Gd
 * (1−)
 * 159Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 96
 * 158.929089(8)
 * 18.1(1) min
 * β−
 * 159Gd
 * 5/2+
 * 160Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 97
 * 159.93197(22)#
 * 38(4) s
 * β−
 * 160Gd
 * 1(−)
 * 161Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 98
 * 160.93368(32)#
 * 26(3) s
 * β−
 * 161Gd
 * 5/2+#
 * 162Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 99
 * 161.93704(32)#
 * 10.6(10) s
 * β−
 * 162Gd
 * 163Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 100
 * 162.93921(54)#
 * 7.7(4) s
 * β−
 * 163Gd
 * 5/2+#
 * style="text-indent:1em" | 163mEu
 * colspan="3" style="text-indent:2em" | 964.5(10) keV
 * 911(24) ns
 * (13/2−)
 * 164Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 101
 * 163.94299(64)#
 * 4.16(19) s
 * β−
 * 164Gd
 * 165Eu
 * style="text-align:right" | 63
 * style="text-align:right" | 102
 * 164.94572(75)#
 * β−
 * 165Gd
 * 5/2+#
 * rowspan=2|166Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 103
 * rowspan=2|165.94997(86)#
 * rowspan=2|$389 s$
 * β− (99.37%)
 * 166Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n (0.63%)
 * 165Gd
 * rowspan=2|167Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 104
 * rowspan=2|166.95321(86)#
 * rowspan=2|$197 s$
 * β− (98.05%)
 * 167Gd
 * rowspan=2|5/2+#
 * rowspan=2|
 * rowspan=2|
 * β−, n (1.95%)
 * 166Gd
 * rowspan=2|168Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 105
 * rowspan=2|
 * rowspan=2|⇭⇭⇭
 * β− (96.05%)
 * 168Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n (3.95%)
 * 167Gd
 * rowspan=2|169Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 106
 * rowspan=2|
 * rowspan=2|⇭⇭⇭
 * β− (85.38%)
 * 169Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n (14.62%)
 * 168Gd
 * rowspan=2|170Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 107
 * rowspan=2|
 * rowspan=2|⇭⇭⇭
 * β−
 * 170Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 169Gd
 * rowspan=2|
 * rowspan=2|
 * β−, n (1.95%)
 * 166Gd
 * rowspan=2|168Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 105
 * rowspan=2|
 * rowspan=2|⇭⇭⇭
 * β− (96.05%)
 * 168Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n (3.95%)
 * 167Gd
 * rowspan=2|169Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 106
 * rowspan=2|
 * rowspan=2|⇭⇭⇭
 * β− (85.38%)
 * 169Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n (14.62%)
 * 168Gd
 * rowspan=2|170Eu
 * rowspan=2 style="text-align:right" | 63
 * rowspan=2 style="text-align:right" | 107
 * rowspan=2|
 * rowspan=2|⇭⇭⇭
 * β−
 * 170Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 169Gd
 * 170Gd
 * rowspan=2|
 * rowspan=2|
 * rowspan=2|
 * β−, n
 * 169Gd
 * 169Gd

Europium-155
Europium-155 is a fission product with a half-life of 4.76 years. It has a maximum decay energy of 252 keV. In a thermal reactor (almost all current nuclear power plants), it has a low fission product yield, about half of one percent as much as the most abundant fission products.

155Eu's large neutron capture cross section (about 3900 barns for thermal neutrons, 16000 resonance integral) means that most of even the small amount produced is destroyed in the course of the nuclear fuel's burnup. Yield, decay energy, and half-life are all far less than that of 137Cs and 90Sr, so 155Eu is not a significant contributor to nuclear waste.

Some 155Eu is also produced by successive neutron capture on 153Eu (nonradioactive, 350 barns thermal, 1500 resonance integral, yield is about 5 times as great as 155Eu) and 154Eu (half-life 8.6 years, 1400 barns thermal, 1600 resonance integral, fission yield is extremely small because beta decay stops at 154Sm). However, the differing cross sections mean that both 155Eu and 154Eu are destroyed faster than they are produced.

154Eu is a prolific emitter of gamma radiation.

title: Isotopes of europium


text:
Nagyharsány

Nagyharsány (Aršanj, Harschan) is a village in Baranya county, Hungary, near to the Croatian border.

The dispute of Nagyharsány
In 1574 there was a religious dispute in Nagyharsány between the Unitarian preacher, György Alvinczi, and the followers of Calvinism. Alvinczi was condemned to death and killed by his opponents.

The Ottoman authorities wanted to punish the Calvinist community for this deed, and sentenced those guilty to death. In a gesture of compassion, György Válaszúti, the Unitarian preacher of Pécs begged for their pardon - and the Beylerbey of Buda agreed to have them set free.

Until the end of World War II, the inhabitants were Danube Swabians. Most of the former German settlers were expelled to Germany and Austria in 1945–1948, about the Potsdam Agreement.

authors: Double barrel pistol with both opposite direction

title: Nagyharsány