Speaker
Description
The overall goal of nuclear astrophysics is to understand the creation of the elements in the universe and the nucleosynthesis processes that are involved. Nuclear Level Densities (NLD) are used as inputs to calculate reaction rates for nuclear reactions that occur in different stellar environments. NLDs represent the number of excited energy levels present in a nucleus at a specific excitation energy and are challenging to constrain experimentally. Systematic studies of NLDs allows us to examine trends across isotopic chains to develop predictive models for nuclei farther from stability. In this work, the molybdenum isotopic chain was chosen due to the amount of nuclear data available on the NLD and its relevance for astrophysics and applications. TALYS was used to obtain calculations for the NLDs (both phenomenological and microscopic models) for the 93Mo - 110Mo isotopes. Bayesian Analysis was then performed using the available NLD models along with the existing experimental NLD data from the Oslo Method. The experimental data and the theoretical models were compared against each other to identify the trends across the isotopic chain. To provide model-independent NLD constraints for the stable Mo isotopes for our systematic studies, experiments were conducted to measure the NLD for 93Mo and 94Mo using (p,n) and (d,n) reactions on a 93Nb target. Experiments were performed at the Edwards Accelerator Lab at Ohio University using the Time-of-Flight tunnel and the Beam Swinger facility and data are currently under analysis using the Particle Evaporation Method.
In this presentation, I will provide an overview of systematic NLD trends in the Mo isotopic chain and will describe the recent results obtained via the Particle Evaporation Method.
Acknowledgement: This work was supported by the Office of Defense Nuclear Nonproliferation Research and Development within the U.S. Department of Energy’s National Nuclear Security Administration.
References:
[1] Koning, A., Hilaire, S., and Goriely, S., (2023) Eur. Phys. J. A 59, 131
[2] Chankova, R. et al. (2006) Phys. Rev. C, 73, 034311.
[3] Schiller, A. et al. (2003) Phys. Rev. C, 68, 054326.