Random matrix analysis of the monopole strength distribution in 208Pb

• We study statistical properties of the 0+ spectrum of 208Pb in the energy region Ex ≤ 20 MeV. We use the Skyrme interaction SLy4 as our model Hamiltonian to create a single-particle spectrum and to analyze excited states. The finite-rank separable approximation for the particle–hole interaction enables us to perform the calculations in large configuration spaces. We show that while the position of the monopole resonance centroid is determined by one-phonon excitations of 0+, the phonon–phonon coupling is crucial for the description of the strength distribution of the 0+ spectrum. In fact, this coupling has an impact on the spectral rigidity Δ3(L) which is shifted towards the random matrix limit of the Gaussian orthogonal ensembles.

Subject headings

NATURVETENSKAP  -- Fysik -- Subatomär fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Subatomic Physics (hsv//eng)

Publication and Content Type

art (subject category)

ref (subject category)