Speaker
Mr
David Scraggs
(University of Liverpool)
Description
The smartPET project is an attempt to use high purity germanium
detectors for use in positron emission tomography (PET). The current
spatial resolution of PET using BGO and LSO detectors is ~5mm, and
the smartPET project aims to improve spatial resolution to 1mm. Two
planar Germanium detectors with dimensions of will be used in
coincidence; these detectors are pixelated by means of strip
contacts.
By utilising a strip spacing and Pulse Shape Analysis (PSA) it’s
theoretically possible to achieve a spatial resolution. Pulses
arising from direct gamma absorption in particular strips are
accompanied by image charges in adjacent strips. The shape of these
image charges is dictated by the position of photon interaction in
relation to these adjacent strips; the closer to the adjacent strip
the larger the image charge. The amplitude relationship between
image charge and real charge is empirically known to be ~40% (at
maximum), presenting the problem of detecting low amplitude image
charges in noise.
Current work will quantify the ratio of image charge to real charge
and wavelet analysis will be implemented to de-noise signals. Early
results of wavelet analysis appear to be very promising, with
significant (almost total) noise reduction and identification of
~6keV pulses in signals with ~6keV noise. The results from previous
work and current work will be discussed.
Primary author
Mr
David Scraggs
(University of Liverpool)
