Thursday, December 13, 2012

1212.2946 (Gordon Baym et al.)

Dilute helium solutions in particle-physics experiments: response to a
heat source

Gordon Baym, D. H. Beck, C. J. Pethick
Motivated by a proposed experimental search for the electric dipole moment of the neutron (nEDM) utilizing neutron-$^3$He capture in a dilute solution of $^3$He in superfluid $^4 $He, we reanalyze a measurement in a related system by Lamoreaux et al. of the $^3$He density distribution in a dilute solution in the presence of a heat flow. We show, from considering the thermodynamics and hydrodynamics of dilute solutions, that this experiment in fact measures the thermal conductivity of the solution. Calculating the thermal conductivity within a microscopic framework, taking into account phonon-phonon, phonon-$^3$He, and $^3$He-$^3$He scatterings, we find satisfactory agreement of theory with the data, serving to confirm our understanding of the microscopics of the helium in the nEDM experiment.
View original:

No comments:

Post a Comment