Am
Americium
Z 95 243.0 g/molActinide Radioactive
| 223Am | 128 | 223.0458 | 42,700.0 | --- | 10.0 ms | (9/2-) | α→219Np(100%) β⁺→223Pu | 2015 |
| 224Am | 129 | 224.0464 | 43,260.0 | --- | 1.0 ms | --- | α→220Np SF | --- |
| 225Am | 130 | 225.0455 | 42,390.0 | --- | 100.0 µs | (9/2-) | α→221Np SF | --- |
| 226Am | 131 | 226.0461 | 42,970.0 | --- | 100.0 µs | --- | α→222Np SF | --- |
| 227Am | 132 | 227.0453 | 42,180.0 | --- | 20.0 ms | (9/2-) | α→223Np SF | --- |
| 228Am | 133 | 228.046 | 42,850.0 | --- | 100.0 ms | --- | α→224Np SF | --- |
| 229Am | 134 | 229.0453 | 42,180.0 | --- | 1.8 s | (5/2-) | α→225Np(100%) β⁺→229Pu | 2015 |
| 230Am | 135 | 230.046 | 42,870.0 | --- | 40.0 s | (1-) | β⁺→230Pu(100%) β⁺SF(>30%) | 2003 |
| 231Am | 136 | 231.0455 | 42,410.0 | --- | 1.0 m | (5/2-) | β⁺→231Pu α→227Np | --- |
| 232Am | 137 | 232.0466 | 43,420.0 | --- | 1.31 m | (1-) | β⁺→232Pu(96.931%) β⁺SF(0.069%) α→228Np | 1967 |
| 233Am | 138 | 233.0465 | 43,290.0 | --- | 3.2 m | (5/2-) | α→229Np(4.5%) β⁺→233Pu | 2000 |
| 234Am | 139 | 234.0477 | 44,460.0 | --- | 2.32 m | (0-) | β⁺→234Pu(99.993%) α→230Np(0.039%) β⁺SF(0.007%) | 1967 |
| 235Am | 140 | 235.0479 | 44,620.0 | --- | 10.3 m | (5/2-) | β⁺→235Pu(99.6%) α→231Np(0.4%) | 1996 |
| 236Am | 141 | 236.0494 | 46,040.0 | --- | 3.6 m | 5- | β⁺→236Pu(~100%) α→232Np(0.004%) | 1998 |
| 236mAm | 141 | 236.0495 | 46,090.0 | --- | 2.9 m | (1-) | β⁺→236Pu(100%) α→232Np | 2004 |
| 237Am | 142 | 237.05 | 46,570.0 | --- | 1.23 h | 5/2- | β⁺→237Pu(99.975%) α→233Np(0.025%) | 1970 |
| 238Am | 143 | 238.052 | 48,420.0 | --- | 1.63 h | 1+ | β⁺→238Pu(~100%) α→234Np(1e-4%) | 1950 |
| 238mAm | 143 | 238.0547 | 50,920.0 | --- | 35.0 µs | --- | SF(100%) γ→238Am | 1967 |
| 239Am | 144 | 239.053 | 49,390.4 | --- | 11.9 h | 5/2- | EC→239Pu(99.99%) α→235Np(0.01%) | 1949 |
| 239mAm | 144 | 239.0557 | 51,890.0 | --- | 163.0 ns | (7/2+) | SF(100%) γ→239Am | 1969 |
| 240Am | 145 | 240.0553 | 51,510.0 | --- | 2.12 d | (3-) | β⁺→240Pu(~100%) α→236Np(1.9e-4%) | 1949 |
| 240mAm | 145 | 240.0585 | 54,510.0 | --- | 940.0 µs | --- | SF(100%) γ→240Am | 1967 |
| 241Am | 146 | 241.0568 | 52,934.3 | --- | 432.6 y | 5/2- | α→237Np(~100%) SF(3.6e-10%) | 1949 |
| 241mAm | 146 | 241.0592 | 55,130.0 | --- | 1.2 µs | --- | SF(100%) | 1969 |
| 242Am | 147 | 242.0595 | 55,468.0 | --- | 16.02 h | 1- | β⁻→242Cm(82.7%) EC→242Pu(17.3%) | 1949 |
| 242mAm | 147 | 242.0596 | 55,516.6 | --- | 141.0 y | 5- | γ→242Am(99.55%) α→238Np(0.45%) SF(<4.7e-9%) | 1950 |
| 242nAm | 147 | 242.0619 | 57,670.0 | --- | 14.0 ms | (2-) | SF(100%) γ→242Am | 1962 |
| 243Am | 148 | 243.0614 | 57,175.0 | --- | 7.35 ky | 5/2- | α→239Np(~100%) SF(3.7e-9%) | 1950 |
| 243mAm | 148 | 243.0639 | 59,480.0 | --- | 5.5 µs | --- | SF(100%) γ→243Am | 1970 |
| 244Am | 149 | 244.0643 | 59,879.1 | --- | 10.01 h | (6-) | β⁻→244Cm(100%) | 1950 |
| 244mAm | 149 | 244.0644 | 59,968.4 | --- | 26.13 m | 1+ | β⁻→244Cm(99.964%) EC→244Pu(0.036%) | 1950 |
| 244nAm | 149 | 244.0664 | 61,880.0 | --- | 900.0 µs | --- | SF(100%) γ→244Am | 1967 |
| 245Am | 150 | 245.0665 | 61,900.4 | --- | 2.05 h | 5/2+ | β⁻→245Cm(100%) | 1955 |
| 245mAm | 150 | 245.069 | 64,300.0 | --- | 640.0 ns | --- | SF(100%) γ→245Am | 1972 |
| 246Am | 151 | 246.0698 | 64,994.0 | --- | 39.0 m | 7- | β⁻→246Cm(100%) | 1955 |
| 246mAm | 151 | 246.0698 | 65,024.0 | --- | 25.0 m | (2-) | β⁻→246Cm(100%) γ→246Am | 1955 |
| 246nAm | 151 | 246.0719 | 66,990.0 | --- | 73.0 µs | --- | SF(100%) γ→246Am | 1972 |
| 247Am | 152 | 247.0721 | 67,150.0 | --- | 23.0 m | (5/2) | β⁻→247Cm(100%) | 1967 |
| 248Am | 153 | 248.0757 | 70,560.0 | --- | 3.0 m | (3+) | β⁻→248Cm | --- |
| 249Am | 154 | 249.0785 | 73,100.0 | --- | 3.0 m | (5/2) | β⁻→249Cm | --- |