Spherical electron momentum density distribution and Bayesian analysis of the renormalization parameter in Li metal

The Bayesian analysis of the spherical part of the electron momentum densit y was carried out with the goal of finding the best estimation of the spher ically averaged renormalization parameter, z, quantifying the discontinuity in the electron momentum density distribution in Li metal. Three models pa rametrizing the electron momentum density were considered and nuisance para meters integrated out. The analysis show that the most likely value of z fo llowing from the data of Sakurai et al is in the range of 0.45-0.50, while 0.55 is obtained for the data of Schulke et al. In the maximum entropy reco nstruction of the spherical part of the electron momentum density three dif ferent algorithms were used. It is shown that all of them produce essential ly the same results. The paper shows that the accurate Compton scattering e xperiments are capable of bringing information on this very important Fermi ological aspect of the electron gas in a metal.