Precise measurement of the widths of some<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>L</mml:mi></mml:math>x-ray lines of tungsten

Abstract

The widths of the $L$ x-ray lines $L{\ensuremath{\alpha}}_{1}$, $L{\ensuremath{\alpha}}_{2}$, $L{\ensuremath{\beta}}_{1}$, and $L{\ensuremath{\gamma}}_{1}$ of tungsten have been measured to an accuracy of 4-6% with a high-resolution 90-cm-radius bent crystal Cauchois spectrograph, with the use of the photographic-photometric method. The measured values have been compared with those of earlier workers as well as with those obtained from theoretical self-consistent-field calculations. Our values of the $L{\ensuremath{\alpha}}_{1}$ and $L{\ensuremath{\alpha}}_{2}$ widths are in good agreement with those deduced from the recent Dirac-Hartree-Slater estimates of Chen et al. for the $L$ and $M$ subshells. Contrary to results of earlier workers, the width in eV of the $L{\ensuremath{\beta}}_{1}$ line is found to be larger than that of the $L{\ensuremath{\alpha}}_{1}$ line, a result which is in conformity with theoretical predictions. On the other hand, our measured value of the width of the $L{\ensuremath{\gamma}}_{1}({L}_{2}{N}_{4})$ line does not agree with the results of earlier workers, but is in fair agreement with the nonrelativistic estimate of McGuire. The need for a relativistic calculation of the $N$ subshell widths therefore seems to be indicated.