Nucleon density distribution of the proton drip-line nucleus ¹²N studied via reaction cross sections

Reaction cross sections for the proton drip-line nucleus ¹²N on Be, C, and Al targets have been measured at intermediate energies from 60A to 200A MeV. The results are compared with the systematics for stable nuclei and also with the experimental reaction cross section data for ¹²C to show 5–20% enhancement of the present ¹²N data. The nucleon density distribution of ¹²N has been extracted through the χ²-fitting procedure, which is consistent with a single particle nature of the loosely-bound valence proton in the p orbital though the error of the density is still large. The large one-proton removal cross sections observed at the same time also supports the long proton tail in the density distribution. (author)