Recent Advancements in Compton Imaging

                             Bruce Smith

There are a number of reasons that suggest imaging devices that make use of 
Compton cameras could be build for used in homeland security, astronomy, and 
medicine. One such reason is the understanding, which has been recently 
developed by the speaker, of the informational nature of the data produced 
by Compton cameras.  Unlike similar imaging devices, Compton camera data is 
based upon geometric entities known as conical surface integrals.  In the 
past, it was not known how these entities could be processed to form accurate 
images.  Moreover, it was not even known which of these entities were needed 
to produce accurate images. Fortunately, the recently developed informational 
understanding allows the shape, configuration, and motion of the detectors of 
Compton cameras to be designed so that the geometric entities needed to produce
accurate images can be measured. In addition this understanding has made 
possible a reconstruction method that is capable of producing accurate images.

In is talk the advancements made by the speaker will be presented. In 
particular; (1) a  -completeness condition-  for determining appropriate 
shapes, configurations, and motions of the detectors; (2) a reconstruction 
method that takes into account the Doppler broadening, the Klein-Nishini 
distribution, and the variability of the data due to the random decay of 
the isotope will be discussed. In addition, results of simulations, which 
used deterministic computer generated data, will also be presented.