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High-spin states and level structure in stable nucleus strontium-84
Shuifa Shen1, Guangbing Han, Shuxian Wen
11] Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei 230031, China [2] School of Physics, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand [3] State Key Laboratory of Nuclear Physics and Technology (Peking University), Beijing 100871, China [4] Thailand Center of Excellence in Physics (ThEP), Commission on Higher Education, Thailand.
Scientific Reports
|September 25, 2013
Summary
Researchers studied high-spin states in Strontium-84 (84Sr) using nuclear reactions. They identified new energy levels and transitions, extending known bands and observing signature staggering in nuclear structure.
Area of Science:
- Nuclear Physics
- Nuclear Structure and Reactions
Background:
- Understanding nuclear structure at high spins is crucial for testing nuclear models.
- Strontium-84 (84Sr) is an important nucleus for studying collective excitations and deformation.
Purpose of the Study:
- To investigate high-spin states in 84Sr populated via the 70Zn(18O, 4n)84Sr reaction.
- To establish a more complete level scheme for 84Sr, identifying new states and transitions.
- To study signature staggering and deformation in 84Sr.
Main Methods:
- Nuclear reaction: 70Zn(18O, 4n)84Sr at 75 MeV beam energy.
- Experimental techniques: Excitation functions, gamma-gamma coincidences, Directional Correlations of Oriented states (DCO) ratios, and gamma-transition intensity measurements.
- Detection system: Eight anti-Compton HPGe detectors and one planar HPGe detector.
- Theoretical analysis: Total Routhian Surfaces (TRS) calculations in the cranked shell model.
Main Results:
- A new level scheme for 84Sr was established, with 12 new states and approximately 30 new gamma-transitions identified.
- The positive-parity yrast band was extended to spin I(π) = 24(+).
- A negative-parity band was extended to spin I(π) = 19(-), exhibiting signature staggering in its even-spin and odd-spin members.
- Deformation properties of 84Sr were investigated through TRS calculations.
Conclusions:
- The study significantly advances the knowledge of high-spin states in 84Sr.
- The observed signature staggering provides insights into the underlying nuclear symmetries.
- The results contribute to a better understanding of nuclear deformation and collective behavior in this mass region.
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