Design of a Unique Open-Geometry Cylindrical Penning Trap
  The Texas A&M University Penning Trap facility is an upcoming ion trap that will be used to search for possible scalar currents in T=2 superallowed $\beta$-delayed proton decays, which, if found, would be an indication of physics beyond the standard model. In addition, TAMUTRAP will provide a low-energy, point-like source of ions for various other applications at the Cyclotron Institute. The experiment is centered around a unique, compensated cylindrical Penning trap that employs a specially optimized $\mathrm{length}/\mathrm{radius}$ ratio in the electrode structure that is not used by any other facility. This allows the geometry to exhibit an unprecedented 90 mm free radius, which is larger than in any existing trap, while at the same time remaining a tractable overall length. The trap geometry was designed from first principles to be suitable for a wide range of nuclear physics experiments. In particular, the electrode structure is both "tunable" and "orthogonalized", which allows for a near quadrupole electric field at the trap center, a feature necessary for performing precision mass measurements. 
Michael S. Mehlman and Praveen D. Shidling and Richard S. Behling and   Benjamin Fenker and Daniel G. Melconian and Levi Clark
nucl-ex physics.atom-ph