Paul Gueye

My research interest is in experimental nuclear physics with a focus on neutron-rich isotopes along the neutron dripline. I am a member of the MoNA Collaboration that has a long history of studying the properties of neutron-unbound nuclei. We probe their formation (reaction mechanisms) and unravel their nuclear structures. This research provides important insights into the neutron–nucleus interaction far from stability, the coupling to the continuum in neutron-rich systems, and the structure of multi-neutron halos or skins.

We use the invariant mass spectroscopy as the primary technique to probe resonance states using the 4-momenta of the neutron rich decay products (fragments and neutrons). There are two devices uniquely suited to conduct my research: the MoNA-LISA modular neutron array that is composed of 288 bars of 10x10x200 cm3 plastic scintillators (BC408) and a 4 Tm large gap superconducting sweeper magnet.

In close collaboration with my colleagues, we constructed a Be-Si segmented target that improves greatly our energy resolution using position-sensitive silicon detectors. It also permits to increase the effective length of (passive) reaction targets to unravel processes with very low probabilities. This expertise was utilized to develop a new Si-CsI telescope to identify heavy ions from their energy loss (Si) and total energy (CsI) for an upcoming sweeperless experimental program.

I am also utilizing my expertise from medium energy electron scattering to enhance and complement our existing research thrusts such as: (i) designing and testing a highly segmented GEM (gas electron multiplier)-based active target that houses several thin (250-500 μm) beryllium foils for the detection of low energy recoils to enable usage of the missing mass technique to gain additional insights in the reaction mechanisms and dynamics of neutron-rich nuclei; (ii) developing the next generation neutron detectors to provide unprecedented position and timing resolution to upgrade the MoNA-LISA array for the upcoming Facility for Rare Isotope Beams; (iii) building a GEANT4 Monte Carlo simulation general framework to study neutron-rich nuclei; and (iv) investigating the possibilities of polarized targets to study spin dependent observables for rare isotope research.