Abstract
Abstract
An imaging technique utilizing a scintillator plate in
conjunction with a magnifying unit and a cooled electron multiplying
charge-coupled device (EM-CCD) camera shows promise for capturing
high-resolution trajectory images. Nevertheless, in the
2-dimensional trajectory images, the incident directions of the
alpha particles entering the scintillator plate remained unknown due
to the line-shaped trajectories. To elucidate the incident
directions in our trajectory images, we conducted experiments
capturing trajectory images of alpha particles under off-focus
conditions. To capture off-focus images of alpha particles, we
systematically varied the distance between the GAGG plate and the
lens during imaging using an americium-241 (Am-241) source. Through
images obtained at different distances between the GAGG plate and
the lens, we successfully acquired trajectory images with varying
degrees of off-focus, revealing that trajectory images focused on
the upper surface of the GAGG plate exhibited blurred and wider
trajectories in the deeper regions, making the incident directions
of the alpha particles evident. We conclude that the proposed
off-focus method for trajectory imaging of alpha particles holds
promise for estimating the incident directions in the trajectory
images.