A boron-coated CCD camera for direct detection of Ultracold Neutrons (UCN)

TL;DR

This paper introduces a boron-coated CCD camera capable of directly detecting ultracold neutrons with high spatial and energy resolution, significantly improving detection sensitivity and enabling advanced research in quantum physics and neutron imaging.

Contribution

The paper presents a novel boron-coated CCD detector for direct UCN detection, achieving high resolution and signal-to-noise ratio improvements over previous indirect methods.

Findings

Achieved a signal-to-noise ratio improvement of 10^4

Demonstrated sub-pixel position resolution of a few microns

Enabled large-area UCN detection suitable for advanced research

Abstract

A new boron-coated CCD camera is described for direct detection of ultracold neutrons (UCN) through the capture reactions $^{10}$B (n,$\alpha$0$\gamma$)$^7$Li (6%) and $^{10}$B(n,$\alpha$1$\gamma$)$^7$Li (94%). The experiments, which extend earlier works using a boron-coated ZnS:Ag scintillator, are based on direct detections of the neutron-capture byproducts in silicon. The high position resolution, energy resolution and particle ID performance of a scientific CCD allows for observation and identification of all the byproducts $\alpha$, $^7$Li and $\gamma$ (electron recoils). A signal-to-noise improvement on the order of 10$^4$ over the indirect method has been achieved. Sub-pixel position resolution of a few microns is demonstrated. The technology can also be used to build UCN detectors with an area on the order of 1 m$^2$. The combination of micrometer scale spatial resolution, few electrons ionization thresholds and large area paves the way to new research avenues including quantum physics of UCN and high-resolution neutron imaging and spectroscopy.