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arXiv · 1811.03784

Neutron scattering cross section of diamond nanoparticle

Kenji Mishima·Toshiya Otomoa·Kazutaka Ikeda·Hidetoshi Ohshita
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Abstract

Due to their large coherent scattering cross section, diamond nanoparticles (DNPs) are considered as a promising candidate material for a new neutron reflector. For investigation of scattering cross sections of packed samples, we have developed a technique for mechanical compression of DNP powder. Application of 220 MPa allowed us to increase the bulk density from 0.40 g/cm$^3$ to 1.1 g/cm$^3$. The differential cross sections of uncompressed and packed samples were measured using the high-intensity total diffractometer instrument NOVA at J-PARC, covering transfer wavenumbers (q) from 0.6 to 100 nm$^{-1}$. The q dependence for the compressed sample agreed with the theoretical expectation derived from the Born approximation applied to homogeneous spheres with inclusion of a hard-sphere model to account for the inter-particle structure, whereas the results obtained from the powder sample disagreed. This implies that the theoretical description does not well represent the mesoscopic structure of the DNP powder sample.

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Kenji Mishima, Toshiya Otomoa, Kazutaka Ikeda, Hidetoshi Ohshita. 2018-11-09. Neutron scattering cross section of diamond nanoparticle. https://doi.org/10.1051/epjconf%2F201921910005

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