Next Article in Journal
Empirical Line Lists in the ExoMol Database
Previous Article in Journal
Hyperfine Anomaly in Eu Isotopes and the Universiability of the Moskowitz–Lombardi Formula
Open AccessArticle

Monte Carlo Simulation of γγ Correlation Functions

by Mohamed Omer 1,* and Mahmoud Bakr 1,2,*
1
Physics Department, Faculty of Science, Assiut University, Assiut 71516, Egypt
2
Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011, Japan
*
Authors to whom correspondence should be addressed.
Received: 1 January 2020 / Revised: 31 January 2020 / Accepted: 4 February 2020 / Published: 10 February 2020
(This article belongs to the Section Atomic, Molecular and Nuclear Spectroscopy and Collisions)
γ γ correlation functions are mathematical expressions that describe the angular distribution of cascade γ -rays emitted from an atomic nucleus. Cascade transitions may occur in either a two-step deexcitation or through an excitation-deexcitation process of a particular energy level inside the nucleus. In both cases, the nucleus returns to its ground energy state. Spin and parity of the excited state can be determined experimentally using the asymmetry of the angular distribution of the emitted radiation. γ γ correlation functions are only valid for point-like targets and detectors. In the real experiments, however, neither the target nor the detector is point-like. Thus, misassignment of the spin-parity of energy levels may easily take place if only the analytical equations are considered. Here, we develop a new Monte Carlo simulation method of the γ γ correlation functions to account for the extended target and detector involved in spin-parity measurements using nuclear resonance fluorescence of nuclei. The proposed simulation tool can handle arbitrary geometries and spin sequences. Additionally, we provide numerical calculations of a parametric study on the influence of the detection geometry on the angular distribution of the emitted γ -rays. Finally, we benchmark our simulation by comparing the simulation-estimated asymmetry ratios with those measured experimentally. The present simulation can be employed as a kernel of an implementation that simulates the nuclear resonance fluorescence process. View Full-Text
Keywords: angular distribution; nuclear resonance fluorescence; dipole transition; quadrupole transition; spin-parity; Monte Carlo simulation; Geant4 angular distribution; nuclear resonance fluorescence; dipole transition; quadrupole transition; spin-parity; Monte Carlo simulation; Geant4
Show Figures

Figure 1

MDPI and ACS Style

Omer, M.; Bakr, M. Monte Carlo Simulation of γγ Correlation Functions. Atoms 2020, 8, 6.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop