A new boron-coated CCD camera is described for direct detection of ultracold
neutrons (UCN) through the capture reactions 10B
(n,α0γ)7Li (6%) and 10B(n,α1γ)7Li (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 α, 7Li and γ (electron recoils). A
signal-to-noise improvement on the order of 104 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 m2. 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.Comment: 10 pages, 8 figure