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Eta/s ratio in finite nuclei.
1School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel.
Physical Review Letters
|November 13, 2009
Summary
Scientists calculated the shear viscosity to entropy density ratio (eta/s) in atomic nuclei. Findings show this ratio is similar to that observed in high-energy heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC).
Area of Science:
- Nuclear physics
- High-energy physics
- Condensed matter physics
Background:
- Experiments at the Relativistic Heavy Ion Collider (RHIC) indicate that the matter produced exhibits a low shear viscosity to entropy density ratio (eta/s).
- The properties of nuclear matter at low temperatures and finite nuclei are less understood in comparison.
Purpose of the Study:
- To determine the shear viscosity to entropy density ratio (eta/s) in finite atomic nuclei at low temperatures.
- To compare this ratio with values obtained from high-energy heavy-ion collisions.
Main Methods:
- Utilizing experimental data on the widths of giant vibrational states in nuclei.
- Employing theoretical calculations to derive the eta/s ratio from these nuclear properties.
Main Results:
- The calculated eta/s values for finite nuclei were found to be comparable to those measured at RHIC.
- This suggests a universal behavior of eta/s across different systems and energy scales.
Conclusions:
- Finite atomic nuclei at low temperatures possess a low shear viscosity to entropy density ratio (eta/s).
- The findings imply that the near-perfect fluid behavior observed at RHIC may extend to nuclear matter under different conditions.
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