Izvorni znanstveni članak
Influence of three-body correlations in the spectrum of elementary excitations in liquid 4He
Srećko Kilić
; Fakultet građevinskih znanosti, 58000 Split, Yugoslavia
Sažetak
Using the variational ansatz we obtained an appropriate expression for energy of elementary excitations. Reduction to the Jackson-Feenberg form and the numerical computation pointed out the necessity for precision in the perturbation calculation. We also analysed the influence of three-body correlation on the Jackson¬-Feenberg spectrum in convolution approximation. Consequently we used and tested in this way Feenberg as well as Woo form of three-body correlation part of the wave function. It was demonstrated that the influence of Feenberg's three¬-body correlations on convolution approximation is actually insignificant. The same is correct for Woo correlation in phonon region, but in maxon and roton region the influence is about 16% and 5%, respectively. The discrepancy with experimental data of all approximants in maxon and especially in roton region shows that the basis with one and two-phonon funtions describes well only phonons in liquid 4He.
Ključne riječi
Hrčak ID:
328924
URI
Datum izdavanja:
8.8.1983.
Posjeta: 333 *