a positive direct spectrum component;
a positive in-scatter component from floor, walls and ceiling;
a positive in-scatter component from air;
a negative out-scatter (attenuation) component from air.
If the shadow cone is set up properly (no overshadowing present), there are only two components to the CONE measurement. Those are
a positive in-scatter component from floor, walls and ceiling;
a positive in-scatter component from air.
Note that one wants to avoid overshadowing of the detector in order for the air in-scatter components for both CONE and NO-CONE measurements to be identical. When this is satisfied the CONE measurement can be subtracted from the NO-CONE measurement to give the direct spectrum minus those neutrons which have been out-scattered by the air between the source and detector. The correction for air out-scatter is discussed later in the paper.