Resonance width distribution for open quantum systems

Abstract

Recent measurements of resonance widths for low-energy neutron scattering off heavy nuclei show large deviations from the standard Porter-Thomas distribution. We propose a new resonance width distribution based on the random matrix theory for an open quantum system. Two methods of derivation lead to a single analytical expression; in the limit of vanishing continuum coupling, we recover the Porter-Thomas distribution. The result depends on the ratio of typical widths $\Gamma$ to the energy level spacing $D$ via the dimensionless parameter $\kappa =(\pi \Gamma /2D)$. The new distribution suppresses small widths and increases the probabilities of larger widths.

8 pages, 2 figures

References in corpus (3)

• Distribution of Partial Neutron Widths for Nuclei close to a Maximum of the Neutron Strength Function
• Doorway states in nuclear reactions as a manifestation of the "super-radiant" mechanism
• Porter-Thomas distribution in unstable many-body systems

Cited by in corpus (8)

• Resonance width distribution in RMT: Weak coupling regime beyond Porter-Thomas
• Neutron Resonance Widths and the Porter-Thomas Distribution
• Neutron Resonance Data Exclude Random Matrix Theory
• Reflection Time Difference as a probe of S-matrix Zeroes in Chaotic Resonance Scattering
• Quantum signal transmission through a single-qubit chain
• Open quantum systems and Random Matrix Theory
• Cross section versus time delay and trapping probability
• Test of the Porter-Thomas distribution with the total cross section autocorrelation function