Pure Beta Emitters
This is a list of pure beta emitters. These are of interest to those making radioisotope power sources.
These are sorted by half-life.
You can download the data in spreadsheet form here. This will let you sort by other criteria.
There are a handful of isotopes which I would call "almost-pure" beta emitters. These have a gamma abundance of less than 2%. They include As-77, Br-83, La-141, and Cm-249. All have half-lives of less than two days.
One interesting isotope is Ra-228. The half-life is 5.8 years. It has two beta pathways. One has a maximum energy of 14.9 keV and the other is 39.2 keV. There are two gamma pathways, both with energy less than 13.5 keV. The total abundance of the gammas is 5.7%.
All isotopes listed below decay to a stable isotope, unless noted otherwise in the comment column.
isotope | half-life (years) | max energy (keV) | avg energy (keV) | abundance | comments |
---|---|---|---|---|---|
cu-66 | 9.74E-6 | 2640 | 1111 | 1 | |
pb-209 | 0.00038 | 644.4 | 197.5 | 1 | |
0.000685 | 1805 | 683 | 0.95 | has many beta decay pathways - only one is shown here | |
te-127 | 0.00107 | 276 | 78.2 | 0.012 | has multiple beta decay pathways |
te-127 | 0.00107 | 694 | 224.7 | 0.988 | has multiple beta decay pathways |
sn-121 | 0.0030 | 388.9 | 115.2 | 1 | |
ni-66 | 0.0063 | 227 | 65 | 1 | decays to Cu-66, a pure beta emitter with a 29 s half-life |
y-90 | 0.007 | 2281.4 | 933.7 | 1 | |
bi-210 | 0.014 | 1161.5 | 389 | 1 | decays to Po-210, an alpha emitter with a 138 d half-life; also has a small alpha decay channel with an abundance of 0.00013% |
er-169 | 0.0258 | 342.5 | 98.1 | 0.45 | has multiple beta decay pathways |
er-169 | 0.0258 | 350.9 | 100.8 | 0.55 | has multiple beta decay pathways |
pr-143 | 0.037 | 934.5 | 315.3 | 1 | |
p-32 | 0.039 | 1710.3 | 694.9 | 1 | |
p-33 | 0.069 | 248.5 | 76.4 | 1 | |
sr-89 | 0.138 | 1492 | 583.3 | 1 | |
y-91 | 0.160 | 340.9 | 100.8 | 0.003 | has multiple beta decay pathways |
y-91 | 0.160 | 1545.6 | 604.9 | 0.997 | has multiple beta decay pathways |
w-188 | 0.190 | 58 | 14.9 | 0.008 | has multiple beta decay pathways, decays to Re-188, a beta/gamma emitter with a 17 h half-life |
w-188 | 0.190 | 285 | 79.9 | 0.002 | has multiple beta decay pathways, decays to Re-188, a beta/gamma emitter with a 17 h half-life |
w-188 | 0.190 | 349 | 99.7 | 0.99 | has multiple beta decay pathways, decays to Re-188, a beta/gamma emitter with a 17 h half-life |
s-35 | 0.240 | 166.8 | 48.6 | 1 | |
sn-123 | 0.354 | 314 | 90.5 | 0.006 | has multiple beta decay pathways |
sn-123 | 0.354 | 1403 | 525.5 | 0.994 | has multiple beta decay pathways |
ca-45 | 0.445 | 256.8 | 77.2 | 1 | |
bk-249 | 0.877 | 125.7 | 32.4 | 1 | decays to Cf-249, an alpha/gamma emitter with a 351 y half-life |
ru-106 | 1.0 | 39.4 | 10 | 1 | decays to Rh-106, a pure beta emitter with a 30 s half-life and a peak energy of 3.5 MeV |
tm-171 | 1.9 | 29.7 | 7.5 | 0.02 | has multiple beta decay pathways |
tm-171 | 1.9 | 96.4 | 25.1 | 0.98 | has multiple beta decay pathways |
pm-147 | 2.6 | 224.6 | 62 | 1 | decays to Sm-147, an alpha emitter with a very long half-life |
kr-85 | 10.8 | 173.4 | 47.65 | 0.004 | has multiple beta decay pathways |
kr-85 | 10.8 | 687.4 | 251.6 | 0.996 | has multiple beta decay pathways |
h-3 | 12.3 | 18.6 | 5.7 | 1 | |
cd-113m | 14.1 | 580 | 185.4 | 1 | also has a small isomeric transition channel with an abundance of 0.14% and a decay energy of 264 keV |
pu-241 | 14.4 | 20.8 | 5.2 | 1 | decays to Am-241, an alpha/gamma emitter with a 432 y half-life |
sr-90 | 28.8 | 546.2 | 195.8 | 1 | decays to Y-90, a beta emitter with a 2.7 d half life |
ar-42 | 32.9 | 600 | 233 | 1 | decays to K-42, a beta/gamma emitter with a 12.4 h half-life |
sm-151 | 90.1 | 54.8 | 13.96 | 0.009 | has multiple beta decay pathways |
sm-151 | 90.1 | 76.3 | 19.68 | 0.991 | has multiple beta decay pathways |
ni-63 | 100.2 | 66.9 | 17.4 | 1 | |
si-32 | 172.1 | 225 | 68.8 | 1 | decays to P-32, a pure beta emitter with a 14 d half-life |
ar-39 | 269.2 | 565 | 218.8 | 1 | |
c-14 | 5734 | 156.5 | 49.5 | 1 | |
tc-99 | 2.1E+05 | 293.5 | 84.6 | 1 | |
se-79 | 6.5E+05 | 150.7 | 55.8 | 1 | |
be-10 | 1.5E+06 | 556.2 | 202.6 | 1 | |
cs-135 | 2.3E+06 | 205 | 56.3 | 1 | |
pd-107 | 6.5E+06 | 33 | 9.3 | 1 | |
re-187 | 4.4E+10 | 2.6 | 0.7 | 1 | |
in-115 | 4.4E+14 | 497 | 152 | 1 | |
cd-113 | 9.3E+15 | 316 | 93.3 | 1 |
- Table of Nuclides at KAERI
- The Risk Assessment Information System at ORNL
- "Pocket Guide for Radiological Management," published by Perma-Fix Environmental Services