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Two-Nucleon Spectral Function in Infinite Nuclear Matter

Omar Benhar·Adelchi Fabrocini
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Abstract

The two-nucleon spectral function in nuclear matter is studied using Correlated Basis Function perturbation theory, including central and tensor correlations produceded by a realistic hamiltonian. The factorization property of the two-nucleon momentum distribution into the product of the two single nucleon distributions shows up in an analogous property of the spectral function. The correlated model yields a two-hole contribution quenched whith respect to Fermi gas model, while the peaks acquire a quasiparticle width that vanishes as the two momenta approach $k_F$. In addition, three-hole one-particle and more complicated intermediate states give rise to a background, spread out in energy and absent in the uncorrelated models. The possible connections with one- and two-nucleon emission processes are briefly discussed.

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Omar Benhar, Adelchi Fabrocini. 1999-09-08. Two-Nucleon Spectral Function in Infinite Nuclear Matter. https://doi.org/10.1103/physrevc.62.034304

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