We examined radial intensity profiles of (\mathrm{CN}) jets in comparison with the diffuse, isotropic component of the CN coma of Comet P/Halley. All images were bias-subtracted, flat-fielded, and continuum-subtracted. We calculated the diffuse profiles by finding the azimuthal mean of the coma least contaminated by jets yielding profiles similar to those of vectorial and Haser models of simple photodissociation. We found the jet profiles by calculating a mean around a Gaussian-fitted center in (r) - (\theta) space. There is an unmistakable difference between the profiles of the (\mathrm{CN}) jets and the profiles of the diffuse CN. Spatial derivatives of these profiles, corrected for geometrical expansion, show that the diffuse component is consistent with a simple photodissociation process, but the jet component is not. The peak production of the jet profile occurs (6000 \mathrm{~km}) from the nucleus at a heliocentric distance of (1.4 \mathrm{AU}). Modeling of both components of the coma indicate results that are consistent with the diffuse (\mathrm{CN}) photochemically produced, but the (\mathrm{CN}) jets need an additional extended source. We found that about one-half of the (\mathrm{CN}) in the coma of Comet (P /) Halley originated from the jets, the rest from the diffuse component. These features, along with the width of the jet being approximately constant, are consistent with a CHON grain origin for the jets. O 1994 Academic Press, inc.