Gamow-Teller transition strengths from 56Ni.
M Sasano1, G Perdikakis, R G T Zegers
1National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, 48824-1321, USA.
Physical Review Letters
|December 21, 2011
Summary
A new method measured Gamow-Teller strengths in nickel-56 using charge-exchange reactions. Results improve models of supernovae and electron-capture rates in iron-region nuclei.
Area of Science:
- Nuclear Physics
- Astrophysics
Background:
- Accurate Gamow-Teller (GT) strengths are crucial for nuclear astrophysics.
- Previous measurements were limited, especially for unstable isotopes.
Purpose of the Study:
- Develop a novel technique for measuring (p,n) charge-exchange reactions in inverse kinematics.
- Determine GT transition strengths for Nickel-56 (⁵⁶Ni).
Main Methods:
- Utilized a new technique for (p,n) charge-exchange reactions at intermediate energies.
- Studied the ⁵⁶Ni(p,n) reaction at 110 MeV/u in inverse kinematics.
- Compared experimental data with shell-model predictions (KB3G and GXPF1A interactions).
Main Results:
- Successfully measured GT transition strengths from ⁵⁶Ni to ⁵⁶Copper (⁵⁶Cu).
- The GXPF1A interaction model showed superior agreement with experimental data compared to the KB3G interaction.
- Identified deficiencies in the spin-orbit and proton-neutron residual potentials of the KB3G interaction.
Conclusions:
- The new measurement technique is effective for unstable isotopes.
- The findings refine nuclear models, particularly for the iron region.
- Improved understanding of electron-capture rates aids in modeling supernovae evolution.
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