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Multifaceted Decay of ^{116}Cs
J Dey1,2, U Datta1,2, O Tengblad3
1Saha Institute of Nuclear Physics, Kolkata, India.
Physical Review Letters
|July 23, 2026
Summary
Researchers studied cesium-116 decay properties, discovering new xenon-116 states and observing rare two-proton emission and heavy cluster decay. This provides insights into nuclear structure near the proton drip line.
Area of Science:
- Nuclear Physics
- Radioactive Decay Studies
Background:
- Investigating exotic nuclei near the proton drip line is crucial for understanding nuclear structure and decay mechanisms.
- Cesium-116 (¹¹⁶Cs) decay properties offer a unique window into nuclear behavior under extreme proton-rich conditions.
Purpose of the Study:
- To comprehensively study the decay properties of ^{116}Cs.
- To identify new nuclear states and exotic decay modes in the medium-heavy region.
Main Methods:
- Utilized the ISOLDE facility at CERN for radioactive ion beam experiments.
- Employed advanced detection techniques to identify decay products and measure their properties.
Main Results:
- Identified over six new unbound states in ^{116}Xe.
- Observed a novel low-energy isoscalar octupole resonance.
- Reported the first observation of delayed two-proton emission in the medium-heavy region, significantly rarer than single-proton emission.
- Provided evidence for long-range proton-proton correlation.
- Indicated a rare heavy cluster emission event (¹²C).
Conclusions:
- The decay of ^{116}Cs exhibits complex and exotic phenomena, including new nuclear states and decay modes.
- The observed phenomena challenge and refine current nuclear models.
- This study significantly advances the understanding of nuclear structure and decay at the proton drip line.
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