Projectile fragmentation has been used to produce rare and short-lived nuclei for study at a variety of isotope production beam facilities such as the National Superconducting Cyclotron Laboratory (NSCL). Relatively few exclusive measurements of the final fragments from projectile fragmentation reactions have been made, even though these types of measurements can provide more insight into the production process by comparing the measurements to models that simulate collisions and reactions on nuclei. The present work examines exclusive measurements of neutrons in coincidence with isotopically identified products. Two intermediate-energy (55.5 MeV/u) projectile fragmentation beams of 30S and 40S nuclei were produced and reacted with beryllium targets at the NSCL to produce a wide range of projectile fragments. Resulting heavy residue fragments were measured with the Sweeper magnet charged particle detectors and neutrons were detected in coincidence using the Modular Neutron Array and Large-area multi-Institutional Scintillator Array (MoNA LISA) detectors. A broad range of fragments was identified in each reaction for elements with Z = 6-11. To explore the projectile fragmentation process, the present results were compared to predictions from two different nuclear reaction models. The hit multiplicity distributions observed in MoNA LISA for the summed elemental and individual isotopic products were compared to the two models. The first calculational approach involved the Liège Intranuclear Cascade (INCL++) model, a microscopic model and Monte Carlo based code that considers the reaction as a two-step process with collisions between individual nucleons followed by a de-excitation process of the intermediate and highly excited residue. The second approach involved the Constrained Molecular Dynamics (CoMD) model, a more macroscopic quantum mechanical model that follows the dynamical evolution of nuclear matter using the nuclear equation of state with three options for the symmetry energy term. The output of the CoMD model was coupled to GEMINI++ to de-excite any remaining hot fragments. Results from both simulations were passed through the GEANT4 code to model the neutron response of MoNA LISA to produce simulated hit multiplicity distributions that could be compared to the experimental hit multiplicity distributions. The majority of identified fragments were measured in coincidence with no neutron hits. Because the INCL++ model prediction better matched the proportion of fragments with zero hits and the CoMD + GEMINI++ simulations under-predicted the proportion of fragments produced with zero hits, INCL++ did an overall better job at predicting the observed hit multiplicity proportions. However, INCL++ failed to generate enough events with higher hit counts in MoNA LISA. Furthermore, the three CoMD + GEMINI++ symmetry energy options did not appear to produce noticeably different hit multiplicity distributions and no constraint on the symmetry energy could be made with this experimental data set. The distributions of precursor fragments in both the INCL++ and CoMD models were also examined. Many of the precursor fragments contained more nucleons than the projectile, indicating that both models predict that the projectile picks up nucleons from the target during the initial encounter. This prediction differs from common descriptions of these reactions.
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