Capture of negative muons in cubic and hexagonal structures of carbon and boron nitride

Muonic x-ray intensities of the Lyman series have been measured in carbon (diamond, graphite, and soot) and in boron and nitrogen in the cubic (diamond) and hexagonal (graphite) structures of boron nitride. By means of muon cascade calculations which reproduce the measured intensities, angular momentum distributions of the captured muons have been determined for carbon and nitrogen in the $\mu$-atomic level $n=13\mathrm{}$. The boron-to-nitrogen capture ratios have been found to be 0.233±0.011 in the cubic structure and 0.275±0.012 in the hexagonal structure. The difference of 18±3% has to be attributed to the difference in the solid-state structures.