Americium: Properties


Isotopes
  Natural
Abun. (%)
Atomic
Mass
Half-
life
Decay Mode
/Energy (/MeV)
Part. En.
/Intensity
(MeV/%)
Cross-sect.
Ther. Neut.
(b)
Spin
(h/2 pi)
Magnetic
Dipl.Mom.
(nm)
Electric
Quad. Mom.
(b)
Gamma En.
/Intensity
(MeV/%)
 232Am     0.9m E.C./ 5           
 234Am     2.6m E.C./ 4           
 237Am   237.05005 1.22h E.C./ 1.6
alpha/ 6.2
 
6.042/ 0.02
 5/2-     Pu k x rays
0.14559
0.28026
0.43845
 238Am   238.05198 1.63h E.C./ 2.26
alpha/ 6.04
 
5.94/ 1x10-4
 1+     Pu L x rays
Pu k x rays
0.9187
0.96278
 239Am   239.053016 11.9h E.C./ 0.8
alpha/ 5.924
 
5.734/ 0.001
5.776/ 0.008
 5/2-     Pu L x rays
Pu k x rays
0.18172
0.22818
0.2776
 240Am   240.055278 2.12d E.C./ 1.38
alpha/ 5.592
 
5.378/ 0.0016
 3-     Pu L x rays
Pu k x rays
0.88878
0.98764
0.1 - 1.3
 241Am   241.056823 432.2y alpha/ 5.637 5.3884/ 1.4
5.4431/ 12.8
5.4857/ 85.2
5.116/ 0.2
5.5442/ 0.34
620 b5/2- 1.61 nm 4 b Np L x rays
0.02634
0.03319
0.05954
0.03 - 0.95
 242mAm     141y I.T./ 0.048
alpha/ 5.62
 
5.141/ 0.026
5.207/ 0.4
1700 b5- 1 nm 6.5 b Am L x rays
0.04863
0.08648
0.10944
0.16304
 242Am   242.059541 16.02h -/ 0.663
E.C./ 0.75
0.63/ 46
0.67/ 37
 1- 0.388 nm -2.4 b Pu L x rays
Cm L x rays
Pu k x rays
0.0422
0.04453
 243Am   243.061375 7370y alpha/ 5.438 5.1798/ 1.1
5.2343/ 11
5.2766/ 88
5.394/ 0.12
5.35/ 0.16
80 b5/2- 1.61 nm 4 b 0.04354
0.07467
0.08657
0.1177
0.14197
 244mAm     26m -/ 1.498          0.0429
 244Am   244.064279 10.1h -/ 1.428          Am L x rays
Cm k x rays
0.746
0.9
 245Am   245.066444 2.05h -/ 0.894 0.65/ 19
0.9/ 77
 5/2+     Cm L x rays
Cm k x rays
0.25299
 246mAm     25m - 1.3/ 79
1.6/ 14
2.1/ 7
 2-     Cm L x rays
Cm k x rays
0.27002
0.79881
1.06201
1.07885
0.04 - 2.29
 246Am   246.06977 39m -/ 2.38 1.2  7-     Cm L x rays
Cm k x rays
0.1529
0.2046
0.6786
 247Am   247.07217 22m -/ 1.7          Cm L x rays
Cm k x rays
0.2267
0.2853