A novel approach for extracting model-independent nuclear level densities far from stability
Year: 2020
Type: preprint
Abstract: The level density of quantum states in statistical mesoscopic systems is a critical input for various fields of physics, including nuclear physics, nuclear astrophysics, atomic physics and their applications. In atomic nuclei, the level density is a fundamental measure of their complex structure at relatively high energies. Here we present the first model-independent measurement of the absolute partial nuclear level density for a short-lived unstable nucleus. For this purpose, we introduce the ``Shape method'' to extract the shape of the $γ$-ray strength function. Combining the Shape method with the existing $β$-Oslo technique allows the extraction of the nuclear level density without the need for theoretical input. We benchmark the Shape method using results for the stable $^{76}$Ge nucleus, finding an excellent agreement to previous experimental results. We apply the Shape method to new experimental data on the short-lived $^{88}$Kr nucleus. Our method opens the door for measurements of the nuclear level density and $γ$-ray strength function far away from stability, a pivotal input required to understand the role of exotic nuclei in forming the cosmos.
Source: arXiv (Cornell University)
Authors: Mücher, D., Spyrou, A., Wiedeking, M., Guttormsen, M., Larsen, A. C., Zeiser, F., Harris, C., Richard, A. L., Smith, M. K., Görgen, A., Liddick, S. N., Siem, S., Berg, H., Clark, J. A., DeYoung, P. A., Dombos, A. C., Greaves, B., Hicks, L., Kelmar, R., Lyons, S., Owens-Fryar, J., Palmisano, A., Santiago-Gonzalez, D., Savard, G., von Seeger, W. W.
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3096918104