first, second and third high energy radiation detectors, each configured to detect high energy radiation emitted by a radiation source within an examination object, each detector emitting output signals corresponding to high energy radiation detected by the detector;

a carriage mechanism comprising a support arm having two separated, non-contacting free ends, with said first and second detectors mounted respectively at said free ends, and said third detector being mounted on said arm approximately midway between said free ends, said support arm being configured to encompass, between said free ends, no more than 180° around the examination subject;

a stand unit having a retaining mechanism engaging said carriage mechanism to rotate at least said support arm and said detectors mounted on said support arm around the examination object in a rotation at range that causes said first, second and third detectors, in combination, to detect said high energy radiation emitted by said radiation source within the examination object throughout 360° around the examination object;

an amplifier device that amplifies said output signals from each detector to produce amplified signals;

a signal guidance device that conveys said output signals from each detector to said amplifier device;

a data processing device connected to said amplifier device that processes said amplified signals;

at least one of said amplifier device and said data processing device being contained substantially within said stand unit; and

said stand unit engaged with said carriage mechanism forming a mobile unit.