Locating nuclear-powered submarines with antineutrinos

TL;DR

This paper explores the feasibility of detecting nuclear submarines using antineutrino detectors, analyzing detection capabilities, technological considerations, and strategic deployment in congested waterways.

Contribution

It provides a detailed feasibility assessment of antineutrino-based submarine detection, including scaling relations, detector configurations, and strategic implications.

Findings

A 20 kt detector in Gibraltar can achieve a local detection score of 2.54.

Three detectors in a line increase the score to 4.66.

Detecting submarines across broad ocean passages requires significantly larger detector arrays.

Abstract

Nuclear-powered submarines are difficult to track with conventional methods in congested waterways. We revisit antineutrino-based detection as a barrier concept, analogous to a neutrino-enabled SOSUS-style fence in strategic straits. Using analytic scaling relations and numerical estimates, we show that detectability depends primarily on closest approach, detector depth, and deployed mass. For representative assumptions, a 20\,kt detector in the Strait of Gibraltar reaches a local benchmark score $Z_A\simeq2.54$ for an assumed 100\,MW thermal-power sensitivity-study case in a conservative worst-case transit (with Poisson operating point $(P_\mathrm{FA},P_\mathrm{det})\simeq(5.5\times10^{-3},0.51)$ at threshold $k=2$), while a three-detector line raises the mapped score to $Z_A\simeq4.66$. For broad ocean passages such as GIUK, required detector counts are substantially larger; in the baseline maximum passing distance $\mathrm{PDD}_{\max}=5$\,km geometry, about 80 detectors yield only $Z_A\sim1.6$. The paper outlines detector technology choices, statistical assumptions, and deployment constraints for a first-generation feasibility assessment.