TY - JOUR
T1 - Microscopic self dynamics in liquid hydrogen and in its mixtures with deuterium and neon
T2 - A neutron scattering study
AU - Celli, M.
AU - Colognesi, D.
AU - Zoppi, M.
AU - Ramirez-Cuesta, A. J.
PY - 2005/2
Y1 - 2005/2
N2 - By means of inelastic neutron scattering measurements, we have extracted the incoherent scattering function of liquid para-hydrogen, pure and mixed with deuterium or neon, in various thermodynamic conditions. The low-energy parts of the neutron spectra recorded in forward scattering on TOSCA-II were analyzed in the framework of the Gaussian approximation and filled through a Levesque-Vertet model for the velocity auto-correlation function. These correlation functions derived from the forward-scattering data appear totally unable to properly describe the backward-scattering ones. These findings prove a breakdown of the Gaussian approximation for semi-quantum liquids in the kinematic range of our experiment. The present results appear of extreme interest and suggest further investigation on the limits of the widely-used Gaussian approximation.
AB - By means of inelastic neutron scattering measurements, we have extracted the incoherent scattering function of liquid para-hydrogen, pure and mixed with deuterium or neon, in various thermodynamic conditions. The low-energy parts of the neutron spectra recorded in forward scattering on TOSCA-II were analyzed in the framework of the Gaussian approximation and filled through a Levesque-Vertet model for the velocity auto-correlation function. These correlation functions derived from the forward-scattering data appear totally unable to properly describe the backward-scattering ones. These findings prove a breakdown of the Gaussian approximation for semi-quantum liquids in the kinematic range of our experiment. The present results appear of extreme interest and suggest further investigation on the limits of the widely-used Gaussian approximation.
UR - http://www.scopus.com/inward/record.url?scp=23844528793&partnerID=8YFLogxK
U2 - 10.1007/s10909-005-2320-1
DO - 10.1007/s10909-005-2320-1
M3 - Article
AN - SCOPUS:23844528793
SN - 0022-2291
VL - 138
SP - 887
EP - 892
JO - Journal of Low Temperature Physics
JF - Journal of Low Temperature Physics
IS - 3-4
ER -