Fermi's golden rule applied to the gamma decay in the quasicontinuum of 46Ti

TL;DR

This study uses particle-gamma coincidence data from 46Ti inelastic scattering to simultaneously extract level density and radiative strength functions, revealing a universal RSF above 3 MeV with some fluctuations at lower energies.

Contribution

It demonstrates a method to extract level density and RSF simultaneously from coincidence data and shows the universality of RSF at higher excitation energies in 46Ti.

Findings

Consistent level density across different excitation energies.

Universal RSF observed above 3 MeV.

RSF fluctuations at low energies due to Porter-Thomas effects.

Abstract

Particle-gamma coincidences from the 46Ti(p,p' gamma)46Ti inelastic scattering reaction with 15-MeV protons are utilized to obtain gamma-ray spectra as a function of excitation energy. The rich data set allows analyzing the coincidence data with various gates on excitation energy. This enables, for many independent data sets, a simultaneous extraction of level density and radiative strength function (RSF). The results are consistent with one common level density. The data seem to exhibit a universal RSF as the deduced RSFs from different excitation energies show only small fluctuations provided that only excitation energies above 3 MeV are taken into account. If transitions to well-separated low-energy levels are included, the deduced RSF may change by a factor of 2-3, which might be expected due to the involved Porter-Thomas fluctuations.