NUCLEONICS DATA SHEET No. 22 
Gamma-Ray Spectra 
Radionuclides Arranged by Gamma-Ray Energy 
By GILBERT W. SMITH and DONALD R. FARMELO 
Curtiss-Wright Corp., Quehanna, Pennsylvania 
THE TABLE presented here lists radio- 
nuclides in order of the energies of their 
emitted photons. The listing covers 
the literature to October, 1956, as given 
by the Table of Isotopes (1) and the 
annual cumulations of nuclear data in 
Nuclear Science Abstracts. 
The following criteria have been used 
in selecting the items: 
e Nuclides derived from n,y reac- 
tions and fission products having 
>~0.5% yield are included. 
gamma-scintillation spectrometry, the 
list includes other data along with 
photopeak energy. The list is also 
useful in finding photon energies for 
calibration purposes. 
Photopeaks must not be confused 
with other peaks (2): (a) Pair-produc- 
tion peaks appear 0.51 and 1.02 Mev 
below the photopeak and are especially 
bothersome if the photopeak occurs 
above 1.5 Mev. (b) Annihilation ra- 
diation appears at 0.51 Mev in positron 
X-ray line in kev can be computed 
from its wave length » in angstroms 
as 12.34/X. 
Radiochemical separations may be 
necessary before using the table if a 
complex mixture has more than 5 
photopeaks. Half-life, detection effi- 
ciency, daughter activities, and other 
properties can be used to resolve situa- 
tions of this kind. 
BIBLIOGRAPHY 
e  Half-lives or precursor half-lives 
are a few minutes or longer. 
e Gammas <10% of the total ac- 
tivity of any nuclide are omitted. 
For use in identifying nuclides by 
emitters. 
Mev (3). 
(c) Compton collisions that 
scatter the photon at 180 deg create a 
peak at the following energy: E = E,/ 
(1 + 3.91370) with both energies in 
(d) The energy of the Ka 
1. J. M. Hollander, I. Perlman, G. T. Seaborg, 
Revs. Mod. Phys. 26, 469 (1953) 
2. P. R. Bell, ‘‘The Scintillation Method,” in 
‘Beta and Gamma-Ray Spectroscopy,’’ K. 
Siegbahn, ed. (Interscience Publishers, New 
York, 1955) 
$8. B. Crasemann, H. Easterday, NucLEontIcs 14, 
No. 6, 63 (1956) 
Radionuclides by Increasing Gamma-Photon Energy 
Production Photon Production Photon 
cross yield cross yield 
Photo- section * per Photo- section* per 
peak (barns) or  disinte- peak (barns) or disinte- 
energy Half- fission gration energy Half- fission gration 
(Mev) Nuclide life yield (%) (%) Daughter (Mev) Nuclide life yield (%) (%) Daughter 
0.037 Br®™ 4.58h 2.9b 100 ~=—Br® 0.113c Er!) 7.5h 9b Tm" 
0.040) Rh!" 57m 2.9% 100 = Rh?°8(st) ¢ 0.123c Eu 16y 420b Gd?*4(st) 
0.047. Pb7° 8=22y ~100 ~——Bi0 0.128 Cs! 3.2h 0.016b 100 Cs!4 
0.049 Br8™ 4.58h 2.9b 100 ~=Br® 0.129 Os1! 16.0d 8b 100 _—Ir!*!(st) 
0.052. Rh!" 4.4m 12b 100 Rh 0.132 Hf) 46d 10b Ay Ol 
0.058, Gd's* 18h 4b Tb?!59(st) 0.134 Cel44 290d 6.0% 30 3=Pri4 
0.068ct Ta!®? 112d 21b W?®2(st) 0.136c Se75 127d 26b As75 
0.077 =Pt}87 10h 1.1b 100 Au?*7(st) 0.140 Te%™ 6.04h 5.8% 99 Tes 
0.080 Ho'® 27.3h 60b Er1s6" 0.142 Cel 32.8d 0.3b,5.7 % 67 ~— Pr!41(st) 
0.081 Xe 5.27d 6.5% Cs!33(st) 0.147 Tel 24.8m 0.22b,2.9% §5 a 
0.084 Tm!” 129d 125b Yb!7°(st) 0.150 Cd'™: 49m 0.2b 100) =Cdttim, 
qs 0.150 Kr85™ 4.36h 0.1b,1.1% Kr8s 
0.084 Th?7* 1.9y 28 Ra? 0.155 Re 16.9h 70b Os!88(st) 
0.087 =Pd'% 13.6h 12b Agitem 0.16 Ba!40 12.8d 4.0b,6.3% 60 =La4o 
0.089 = Lu’é"— 3.7h- 40b 100 Hf!78(st) 0.16 Xel3im: 12.0d 2.9% § Xe!31(st) 
Hf!76™ short 0.162 Ba? 85.0m 0.5b,6.2% 26 La!39 
0.089 Te!27™ 110d 0.09b Te!?? 0.176 Se8 25m 0.004b Br83 
0.092 Nd? 11.3d 1.8b,2.6% Pm147 0.177 Te3!™ 30h 0.42% Tels 
0.093 Th*4 24.1d 20 Pa2s4 0.180 Tal82™ 16.5m 0.03b 100!" | Tats? 
0.094 Us 7.1X108y Th?3! 0.184 U2 7.1X108y Th?3! 
0.100 Sm! 47h 140b Kuss 0.188 Ra%6 1622y 6) | R22? 
0.103 Gd} 236d <125b Eu!53(st) 0.190 Int 49d 56b 100 Cd? 
0.105 Pa? 27.4d ~50b U333 0.191 Mo?! 14.6m 0.20b,5.4% Tc! 
0.105 Sm! 2.4m 5.5b 100 =Eu?55 0.206 = Lu!”? 6.8d 4X10%b Hf!77(st) 
0.106 Te'?*™ 33.5d .015b,0.34% 100 Te}29 0.216c Hf!89™ 5.5h 75b 100 Hf!80 
0.110 Te#5™ 58d 5b 100 Te!28(st) 0.231 Te'32 77.7h 4.4% 40 32 
0.112) Lu!” 6.8d 4X10*b Hf!77(st) 0.234 Xel33m 23d 6.5% 100 Xess 
230 
