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The 44Ti(alpha,p) reaction and its implication on the 44Ti yield in supernovae
1Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA.
Physical Review Letters
|October 4, 2000
Summary
Measurements of the 44Ti(alpha,p)47V reaction show higher cross sections than predicted. This impacts titanium-44 yields in supernovae and gamma-ray detection searches.
Area of Science:
- Nuclear astrophysics
- Supernova nucleosynthesis
- Radioactive ion beam applications
Background:
- Titanium-44 (44Ti) is a key element produced in supernovae.
- Accurate measurements of 44Ti production reactions are crucial for understanding supernova remnants.
- Previous theoretical models did not fully capture the reaction dynamics.
Purpose of the Study:
- To experimentally determine the cross sections for the 44Ti(alpha,p)47V reaction.
- To calculate the astrophysical reaction rates based on experimental data.
- To assess the impact of these findings on supernova models and gamma-ray astronomy.
Main Methods:
- Utilized a beam of radioactive 44Ti.
- Measured reaction cross sections in the center-of-mass energy range of 5.7 MeV to 9 MeV.
- Deduced astrophysical reaction rates from the measured cross sections.
Main Results:
- Measured cross sections for the 44Ti(alpha,p)47V reaction were found to be significantly larger than theoretical predictions.
- The deduced astrophysical reaction rates are approximately double the values from current theoretical calculations.
- This suggests a potentially higher yield of 44Ti in supernovae than previously estimated.
Conclusions:
- Experimental data indicates a higher 44Ti production rate in supernovae than predicted by theory.
- The enhanced reaction rate has implications for interpreting observations from space-based gamma-ray detectors searching for supernovae.
- Further refinement of nuclear reaction models is needed to match experimental observations.
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