nucreonics DATA SHEET no. 1 
X-Ray Critical-Absorption and 
Emission Energies in kev 
By S. FINE and C. F. HENDEE 
Philips Laboratories 
Irvington on Hudson, New York 
Increased use of energy-proportional 
detectors for X-rays has created a need 
for a table of energy values of K and 
L absorption and emission series. 
The table presented here includes 
all elements. Most values were ob- 
tained by a conversion to kev of tabu- 
lated experimental wavelength values 
(1-3); some are from previous energy- 
value compilations (4, 5). Where a 
choice existed, the value chosen was 
the one derived from later work. Cer- 
tain values were determined by inter- 
polation, using Moseley’s law. (All 
this is annotated in footnotes.) 
The conversion equations relating 
energy and wavelength used are (6) 
E (kev) = (12.39644 + 0.00017)/A(A) 
= 12.39644/1.002020 \(kX unit) 
In computing values the number of 
places retained sufficed to maintain the 
uncertainty in the original source value. 
The values in the table have been listed 
uniformly to 1 ev. However, chemical 
form may shift absorption edges as 
much as 10-20 ev (4, 5). 
To discover computational errors a 
fit was made to Moseley’s law. In 
general the values were consistent, 
however there were a few irregularities 
due to the deviation of some input 
values (1). These were retained in the 
Physical Constants 
body of the table but a set of values 
calculated to fit better are footnoted. 
* * * 
The authors wish to express their apprecia- 
tion to W. Parrish far helpful suggestions and 
to H. Kasper for performing the computation 
in connection with this work. 
BIBLIOGRAPHY 
1. Y. Cauchois, H. Hulubei, “Tables de Con- 
stantes et Donnees Numeriques, I, Longueurs 
D'Onde des Emissions X et des Discontinuites 
D'Absorption X"’ (Hermann et Cie, Paris 
France, 1947) 
2g. A. H. Compton and §. K. Allison, ‘‘ X-rays in 
Theory and Experiment’’ (D. Van Nostrand 
Co., Inc., New York, 1951) 
8. C. E. Moore, ‘Atomic Energy Levels,"" NBS 
467 (National Bureau of Standards, U. S. 
Department of Commerce, Washington, D. C., 
1949) 
4. Y. Cauchois, J. phys. radium 18, 113 (1952) 
6. R. D. Hill, E. L. Church, and J. W. Mihelich, 
Rev. Sci. Instr. 28, 523 (1952) 
6. J. W. M. DuMond, E. R. Cohen, Phys. Rev. 
82, 555 (1951) 
ed 
X-Ray Critical-Absorption and Emission Energies in kev 
Atomic K series 
Num- 
ber Element Kab KB: KB. Kai Kaz JT tab Litab 
1 Hydrogen 0.0136t 
2 Helium 0.0246f 
3 Lithium 0.055 0.052 
4 Beryllium 0.116§ 0.110 
5 Boron 0.192t 0.185 
6 Carbon 0.283 0.282 
7 Nitrogen 0.399 0.392 
8 Oxygen 0.531 0.5238 
9 Fluorine 0.687T 0.677 
10 Neon 0.874* 0.851§ 0.048¢ 0.022f 
11 Sodium 1.08* 1.067 1.041 0.055§ 0.034§ 
12 Magnesium 1.303 1.297 1.254 0.063 0.050 
13. Aluminum 1.559 1.553 1.487 1.486 0.087 0.073** 
14 Silicon 1.838 1.832 1.740 1.739 0.118* 0.099** 
15 Phosphorus 2.142 2.186 2.015§ 2.014§ 0.153* 0.129§ 
16 Sulphur 2.470 2.464 2.808 2.306 0.193* 0.164** 
17 Chlorine 2.8199 2.815 2.622 2.621 0.238* 0.203§ 
18 Argon 3.203 3.192§ 2.957 2.955 0.287* 0.247** 
19 Potassium 3.607 3.589 3.313 3.310 0.341* 0.297** 
20 Calcium 4.038 4.012 3.691 3.688 0.399* 0.352 
21 Scandium 4.496 4.460 4.090 4.085 0.462* 0.411** 
22 Titanium 4.964 —4.931 4.510 4.504 0.530* 0.460** 
23 Vanadium 5.463 —5.427 4.952 4.944 0.604* 0.519** 
24 Chromium 5.988 —5.946 5.414 5.405 0.679* 0.583** 
25 Manganese 6.537 6.490 5.898 5.887 0.762* 0.650** 
26 Iron 7.111 7.057 6.403 6.390 0.849* 0.721** 
27 Cobalt 7.709 7.649 6.930 6.915 0.929* 0.794** 
28 Nickel 8.331 8.328 8.264 7.477 7.460 1.015* 0.871** 
29 Copper 8.980 8.976 8.904 8.047 8.027 1.100* 0.953 
30 Zinc 9.660 9.657 9.571 8.638 8.615 1.200* 1.045 
L series 
Inte Ly: Lp2 Lf Lai Laz 
0.022t 
0.034§ 
0.049 
0.072** 
0.098** 
0.128§ 
0.163** 
0.202§ 
0. 245** 
0.294** 
0.349 0.344 0.341 
0.406** 0.399 0.395 
0.454** 0.458 0.452 
0.512** 0.519 0.510 
0.574** 0.581 0.571 
0.639** 0.647 0.636 
0.708** 0.717 0.704 
0.779** 0.790 0.775 
0.853** 0.866 0.849 
0.933 0.948 0.928 
1.022 1.032 1.009 
Se ULE EEEEEEEEEESEESSESEESE 
