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Coherent bremsstrahlung in the alpha + p system at 50 MeV/nucleon
1Kernfysisch Versneller Instituut, Zernikelaan 25, NL-9747 AA Groningen, The Netherlands.
Physical Review Letters
|September 6, 2000
Summary
Coherent bremsstrahlung from 200 MeV alpha particles interacting with protons was measured. The study observed classical behavior at low energies and capture into Lithium-5 states at higher energies, challenging theoretical models.
Area of Science:
- Nuclear Physics
- Quantum Electrodynamics
- Particle Physics
Background:
- Coherent bremsstrahlung is a key phenomenon in particle interactions.
- Understanding photon emission spectra provides insights into nuclear reactions.
- Previous models struggled to consistently describe both bremsstrahlung and radiative capture.
Purpose of the Study:
- To measure and analyze the photon spectrum from 200 MeV alpha particle and proton interactions.
- To investigate the contributions of coherent bremsstrahlung and radiative capture.
- To provide experimental data for testing theoretical models of these processes.
Main Methods:
- Experimental measurement of photons from 200 MeV alpha + proton reactions.
- Analysis of the bremsstrahlung spectrum over a wide dynamic range.
- Comparison of experimental data with theoretical predictions.
Main Results:
- Observed classical 1/E(gamma) bremsstrahlung spectrum at low photon energies.
- Detected significant contributions from capture into unbound states of Lithium-5 at higher energies.
- Experimental spectrum deviates from simple theoretical predictions, particularly in relative intensities.
Conclusions:
- The study provides the first comprehensive test of models describing both bremsstrahlung and radiative capture in this system.
- Theoretical calculations qualitatively reproduce observed spectral features.
- Current models fail to accurately predict the relative contributions of bremsstrahlung and capture processes.
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