Andrew Davies, Westmont College / Michigan State UniversityTitle: Measurement Of Electric Quadrupole And Magnetic Dipole Moments Of b-Unstable Nuclei Using Combined NMR And LMR SpectroscopyAuthors: A. Davies, J. Mitchell, W.F. Rogers (Westmont College); G. Georgiev, N. Coulier, S. Teughels, G. Neyens (University Of Leuven, Belgium); P. Mantica, J. Pond (National Superconducting Cyclotron Laboratory, Michigan State University)Abstract: We have begun a program of applying combined b-NMR and b-LMR spectroscopy to the measurement the moments of b-unstable nuclei at the National Superconducting Cyclotron Laboratory at Michigan State University, to complement the ongoing b-NMR measurements already being done there. Of interest are members of T=1 and T=3/2 multiplets for the extraction of the isoscalar and isovector portions of the nuclear current, and nuclei far from the line of stability. In part one of a two part experiment we studied the T=1 nucleus 32Cl (T1/2 = 0.297 sec). 32Cl fragments were produced in the fragmentation of a 100MeV/u 36Ar beam on a Nb target. Polarized fragments emerging from the target at 2 degrees to the beam axis were mass separated using the A1200 and implanted in a cubic NaCl single crystal. By applying b-NMR spectroscopy we were able to determine the moment to about 5%. In the second part of the experiment we plan to produce aligned nuclei, implant them in a non-cubic MgF crystal and perform b-LMR spectroscopy. The electric field gradient (EFG) at the implantation site couples with the nuclear quadrupole moment and causes certain Zeeman levels to cross as a function of external magnetic field. Finding these resonant fields yields the quadrupole frequency to magnetic moment ratio. Hence, by combining results from both parts we can extract the individual quadrupole and dipole moments.This project was supported by the National Science Foundation. |