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Fine structure in proton emission from 145Tm discovered with digital signal processing
M Karny1, R K Grzywacz, J C Batchelder
1IFD, Warsaw University, Pl-00681 Warsaw, Hoza 69, Poland.
Physical Review Letters
|February 7, 2003
Summary
Researchers discovered fine structure in proton emission from Thulium-145 (145Tm) using advanced digital signal processing. This finding reveals proton transitions to the ground and excited states of Erbium-144 (144Er).
Area of Science:
- Nuclear Physics
- Atomic Physics
- Quantum Mechanics
Background:
- Proton emission is a key process in understanding nuclear structure and decay pathways.
- Investigating exotic isotopes like Thulium-145 (145Tm) provides insights into nuclear forces and stability.
Purpose of the Study:
- To investigate the fine structure in proton emission from the 3.1(3) microsecond activity of 145Tm.
- To analyze the proton transitions and branching ratios to specific states in the daughter nucleus, Erbium-144 (144Er).
Main Methods:
- Utilized a novel technique involving digital processing of overlapping recoil implantation and decay signals.
- Applied particle-core vibration coupling models to analyze the nuclear wave function and emission process.
Main Results:
- Discovered fine structure in proton emission from 145Tm.
- Observed proton transitions to the ground state and the first excited 2(+) state (at 0.33(1) MeV) of 144Er.
- Determined a branching ratio I(p)(2(+))=9.6+/-1.5% for the transition to the excited state.
Conclusions:
- The observed fine structure provides detailed information about the energy levels and nuclear configurations involved in proton emission.
- The study enhances the understanding of nuclear wave function structure and proton emission dynamics in this mass region.
- Particle-core vibration coupling models successfully describe the observed phenomena, validating theoretical approaches.
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