Georg Berg

Research Interests

During most of my career I studied the structure and reactions mechanisms of nuclei using magnet spectrometers. However, I was seldom satisfied with the “design” performance of the ion-optical instrument and I often found better techniques and designs leading invariably to new physics that could be explored. This includes “fully dispersion matched” magnet systems that can measure angular distributions at and near 0^o with spectral resolutions an order of magnitude better than the momentum spread of the incident beam. This allowed studies of very proton rich nuclei via the (⁴He,⁸He) reaction to identify resonance levels important in the explosive stellar rp-process; the measure-ment of Gamow-Teller and spin-isospin strength distributions up to high excitation energies due to the capability to measure at 0^o with resolutions better than 30 keV. This is nearly an order or magnitude better compared to the pioneering (p,n) reaction.

After completing the design, construction and successful test of the Fragment Separator (TRImP) I came to Notre Dame with the mission to develop for JINA (Joint Institute of Nuclear Astrophysics) frontier center at the Nuclear Structure Laboratory a recoil separator that will allow the study of the (a,g) and with a later upgrade the (p,g) reaction in inverse kinematics at energies lower than presently possible with other instruments. This will allow efficient studies of these reactions closer to the energies that are prevalent in stars. A large higher order corrected solid angle and a newly designed and optimized Wien Filter allow for the high mass separation of about 100.