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Updated: Jun 21, 2026
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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Near-threshold photoproduction of Lambda(1520) from protons and deuterons
N Muramatsu1, J Y Chen, W C Chang
1Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047, Japan.
Physical Review Letters
|August 8, 2009
Summary
Researchers studied Lambda(1520) photoproduction using hydrogen and deuterium targets. They observed significant cross-section asymmetries between protons and neutrons, indicating the role of the contact term in this particle production.
Area of Science:
- Nuclear Physics
- Particle Physics
- Hadron Spectroscopy
Background:
- The Lambda(1520) is a key resonance in understanding meson production.
- Investigating photoproduction provides insights into the underlying reaction mechanisms.
Purpose of the Study:
- To measure differential cross sections for Lambda(1520) photoproduction.
- To explore the role of the contact term and t-channel K exchange.
- To analyze asymmetries in production from proton and neutron targets.
Main Methods:
- Utilized the SPring-8 LEPS experiment with liquid hydrogen and deuterium targets.
- Examined photon energies below 2.4 GeV.
- Measured differential cross sections, decay asymmetry, and photon beam asymmetry.
Main Results:
- First measurement of differential cross sections at low energies and with a deuterium target.
- Observed a large asymmetry in production cross sections between protons and neutrons at backward angles.
- Results support the contribution of the contact term alongside t-channel K exchange.
Conclusions:
- The contact term plays a significant role in Lambda(1520) photoproduction.
- Gauge invariance and t-channel K exchange are consistent with experimental data.
- Asymmetries provide crucial information on the reaction dynamics.
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