The coherent neutron scattering amplitudes of boron, nitrogen, and oxygen have been measured by the mirror-reflection method. The measured values are $a_{\mathrm{B}}=(5.40\mathrm{}\pm 0.04)\times {10}^{-13\mathrm{}}$ cm, $a_{\mathrm{N}}=(9.19\mathrm{}\pm 0.11)\times {10}^{-13\mathrm{}}$ cm, and $a_{\mathrm{O}}=(5.80\mathrm{}\pm 0.05)\times {10}^{-13\mathrm{}}$ cm. The nitrogen and oxygen values are in agreement with previous measurements. The boron measurement is discussed with regard to the amplitudes of the separate isotopes, and evidence for a resonance in the ${\mathrm{B}}^{10}$ scattering cross section is given.

• Received 22 January 1965

DOI:https://doi.org/10.1103/PhysRev.138.B1116