DATA SHEET continued 
cle in ~0.3% of thermal-neutron fis- 
sions of U3, U285 and Pu*9, 
Prior to 1953 most yields from the 
thermal-neutron fission of U?*® were 
measured relative to Ba!4°, whose yield 
had been determined absolutely as 
6.17% (7). In Table 2 (p. 82) these 
yields have been renormalized to 6.44% 
for Ba'4°, This seems to be a more 
reliable value obtained from mass- 
spectrometric data, which is also sup- 
ported by recent radiochemical meas- 
urements. Those yields that were 
measured relative to Mo% were nor- 
malized to a 6.06% value for the latter. 
(See references 16, 23 and 51 of Table 2.) 
A few of the more recent radiochemical 
yield determinations (e.g., Sr®°, Mo°, 
Xe!33 and Ba!4°) are comparable to 
the mass-spectrometric measurements. 
No half-lives shorter than 1 sec are 
listed in Table 2. Such very short 
periods would be absent even were it 
not for the experimental difficulty of 
identifying them. As Brolley et al. (8) 
have shown from studies of gross B-ray 
and y-ray fission-product activities, no 
periods below a few tenths of a second 
are formed in appreciable yield. 
The values for the half-lives and the 
branching ratios that are given were 
selected from ‘“‘Table of Isotopes” by 
Hollander, Perlman and Seaborg [Rev. 
Mod. Phys. 25, 469 (1953)]; ‘‘ Nuclear 
Science Abstracts” (1953-1957); and a 
survey of the most recent literature. 
= * = 
Special thanks are due the following for 
supplying unpublished data and for making 
helpful suggestions: J. D. Knight, A. C. 
Pappas, R. A. Sharp, E. P. Steinberg, H. G. 
Thode, R. H. Tomlinson, A. C. Wahl and 
W. Seelmann-Eggebert. This work was per- 
formed under the auspices of the U. S. Atomic 
Energy Commission. The tables are to 
appear in the ‘‘ Handbook of Nuclear Engi- 
neering,’ copyright 1958 by Addison-Wesley 
Publishing Co., Inc. 
BIBLIOGRAPHY 
1. M. G. Inghram in ‘‘ Annual Review of Nuclear 
Science,’’ vol. 4, p. 81 (Annual Reviews, Inc., 
Stanford, 1954) 
2. J. A. Petruska, H. G. Thode, R. H. Tomlinson, 
Can. J. Phys. 88, 693 (1955) 
8. L. E. Glendenin, C. D. Coryell, R. R. Edwards 
in “‘Radiochemical Studies: The Fission Prod- 
ucts,” C. TD. Coryell, N. Sugarman, eds., 
National Nuclear Energy Series IV-9, p. 489 
(McGraw-Hill Book Co., New York, 1951) 
4. A. C. Pappas in ‘‘Proceedings of the Inter- 
national Conference on the Peaceful Uses of 
Atomic Energy," vol. 7, p. 19 (United Nations, 
New York, 1956) 
6. See refs. 18 and 19 of Table 2; also, T. J. Ken- 
nett, H. G. Thode, Phys. Rev. 108, 323 (1956) 
6. K. F. Flynn, L. E. Glendenin, E. P. Steinberg, 
Phys. Rev. 101, 1492 (1956) 
7. E. P. Steinberg, M.S. Freeman, ref. 1 of Table 
2, p. 1378 
8. J. E. Brolley, Jr., D. H. Cooper, W. 8S. Hall, 
M.S. Livingston, L. K. Schlacks, Phys. Rev. 88, 
90 (1951) 
238 
Th?82§ 
(fast) 
(7) 
1.2 
1.62 
2.4 
2.87 
yrs 
(fast) 
(2,6) 
0.12 
4.7 
3.2 
(4.7)f 
Yield (%)* 
73s 
(14 Mev) 
(2,5) 
1,34 
2.28 
43 
(4.3)t 
(5 ‘Ot 
5.4 
Pu29 
(fast) 
(2,4) 
Pu?3® 
(2,8) 
0.072 
0.39 
3.8 
2.87 
5.2 
4.02 
(1,2) 
0.050 
2.7 
3.74 
5.10 
333 
(thermal) (thermal) 
Fission 
product 
9.6-d Sn125 
91-h Sb!27 
8.05-d [131 
Stable Xe!3! 
77-h Te132 
2.3-h [132 
Stable Xe132 
Th23 
(~8 Mev) 
(8) 
0.022 
2.7 
Th233 
(fast) 
(7) 
0.00033 
0.00045 
0.009 
0.020 
1.9 
1.99 
3.65 
0.87 
6.00 
Bat 
6.8 
(hee) 
ys 
(fast) 
(2,6) 
0.0038 
0.40 
0.85 
0.153 
1.38 
2.9 
3.2 
Yield (%)* 
yrs 
(2,5) 
1.16 
Py239 
(2,4) 
Pu239 
(2,8) 
0.00012 
0.085 
oo 
noe 
(1,2) 
0.010 
0.019 
0.79 
U233 
(thermal) (thermal) (fast) (14 Mev) 
Fission 
TABLE 1—Total Cumulative Yields of Fission Products 
product 
49-h Zn72 
5.0-h Ga” 
12-h Ge?? 
38.7-h As7? 
2.4-h Br83 
Stable Kr* 
Stable Kr* 
bY 
ON 
wd And 
20.8-h [133 
5.27-d Xe138 
Stable Kr86 
10.3-y Kr85 
51-d Sr®? 
5.38 
5.65 
6.3 
9.0 
6.2 
5.5 
6.0 
6.6 
5.9 
6.2 
5.7 
(5.6)t 
5.3 
(5.9) 
4.5 
(5.7)t 
5.0 
4.7 
6.6 
5.0 
(5.27)t 
(5.68) f 
5.69 
5.2 
5.8 
5.53 
2.1 
5.06 
5.24 
5.7 
5.68 
6.18 
6.54 
5.1 
>4.9 
ari 
<8.9 
7.16 
6.0 
5.6 
2.6 X 10%y Cyt38 
86-s [136 
33-d Cel! 
Stable Ce!4° 
Stable Xe! 
6.7-h [135 
Stable Xe13¢ 
29-y Cs}87 
84-m Ba!3® 
12.8-d Ba!4o 
Stable Cs!33 
52.5-m [184 
6.7 
5.6 
5.0 
5.2 
5.7 
4.5 
4.5 
4.9 
5.4 
2.2 
5.2 
129 
5.9 
5.6 
6.5 
6.53 
6.70 
5.9 
6.10 
5.60 
1.1 X 10%y Zr 
28-y Sr? 
9.7-h Sr*! 
58-d Y*! 
Stable Zr®! 
Stable Zr®2 
Stable Zr 
65-d Zr 
Stable Mo% 
Stable Zr®6 
17-h Zr®” 
