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07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Two-nucleon knockout spectroscopy at the limits of nuclear stability
E C Simpson1, J A Tostevin, D Bazin
1Department of Physics, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom.
Physical Review Letters
|April 28, 2009
Summary
Sudden nucleon removal reactions probe rare isotope structure. Parallel momentum distributions reveal nucleon angular momentum, providing key spectroscopic insights into nuclear structure.
Area of Science:
- Nuclear Physics
- Atomic and Molecular Physics
- Nuclear Chemistry
Background:
- Sudden single-nucleon removal reactions using fast radioactive beams are essential for investigating the structure of rare isotopes.
- The parallel momentum distribution of heavy residues is sensitive to the removed nucleon's orbital angular momentum, offering significant spectroscopic information.
- Two-nucleon removal reactions extend experimental capabilities to the rarest nuclear species.
Purpose of the Study:
- To demonstrate that residue parallel momentum distributions in two-nucleon removal reactions provide clear spectroscopic signals.
- To determine the angular momentum of removed nucleon pairs and the resulting residue final state spins.
- To apply a formalism to analyze experimental data from neutron-rich 36Mg, neutron-deficient 20Mg, and neutron-rich 26Ne.
Main Methods:
- Utilizing sudden single- and two-nucleon removal reaction theories.
- Analyzing heavy residue parallel momentum distributions.
- Applying formalism to final-state-inclusive and exclusive measurements.
Main Results:
- Parallel momentum distributions in two-nucleon removal reactions clearly indicate the angular momentum of the removed nucleon pair.
- The formalism successfully explains new measurements of like-nucleon pair removal reactions for 36Mg and 20Mg.
- A new decomposition of two-proton knockout data for 26Ne is presented and analyzed.
Conclusions:
- Residue parallel momentum distributions are powerful tools for nuclear spectroscopy in rare isotopes.
- The developed formalism accurately describes nucleon removal reactions, aiding in the determination of nuclear structure.
- This approach enhances the study of exotic nuclei through detailed spectroscopic analysis.
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