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arXiv · 2507.08618

Neutron-induced opalescence in silica glass

S. A. Vasiliev·P. F. Kashaykin·A. L. Tomashuk
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Abstract

Light scattering intensity distribution along the optical fiber length is analyzed, which was measured by optical time domain reflectometry (OTDR) during and after fiber irradiation in a nuclear reactor. The OTDR traces prove to contain two components associated with either radiation-induced attenuation (RIA), or with Rayleigh scattering coefficient (RSC) variation. The RSC increase effect in the first stage of fast-neutron irradiation is argued to be similar to the anomalous scattering buildup near the critical point of the liquid-vapor transition known as critical opalescence. For his reason, the RSC increase due to fast-neutron irradiation can be named neutron-induced opalescence (NIO).

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S. A. Vasiliev, P. F. Kashaykin, A. L. Tomashuk. 2025-07-11. Neutron-induced opalescence in silica glass. https://arxiv.org/abs/2507.08618

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