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07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 16, 2013
Search for three-nucleon force effects in analyzing powers for p-->d elastic scattering
K Ermisch1, A M van den Berg, R Bieber
1Kernfysisch Versneller Instituut, NL-9747 AAGroningen, The Netherlands.
Physical Review Letters
|June 21, 2001
Summary
Measurements of the (2)H(p,pd) reaction revealed deviations from two-nucleon force predictions. Three-nucleon forces did not explain these findings, highlighting gaps in understanding three-nucleon systems.
Area of Science:
- Nuclear physics
- Quantum mechanics
- Few-body systems
Background:
- Understanding nuclear forces is crucial for describing atomic nuclei.
- Two-nucleon forces explain many nuclear phenomena, but three-nucleon interactions are less understood.
- Experimental data on three-nucleon systems provide critical tests for theoretical models.
Purpose of the Study:
- To investigate spin-dependent effects in the three-nucleon system.
- To test the accuracy of theoretical models, including two- and three-nucleon forces.
- To explore physics beyond the standard two-nucleon interaction model.
Main Methods:
- Performed measurements of the vector analyzing power A(y) for the (2)H(p,pd) reaction.
- Covered incident beam energies from 120 to 170 MeV.
- Analyzed data across a range of center-of-mass angles (30° to 170°).
Main Results:
- Observed significant deviations between experimental data and Faddeev calculations based solely on two-nucleon forces.
- Deviations were consistent across all measured energies and for center-of-mass angles between 70° and 130°.
- Including current three-nucleon forces in theoretical models did not improve the agreement with the experimental data.
Conclusions:
- The study highlights the inadequacy of current theoretical models, particularly concerning three-nucleon forces.
- There is a need for improved understanding and modeling of three-nucleon systems.
- Experimental data reveal limitations in current nuclear force theories beyond the two-nucleon interaction.
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