6,322 research outputs found
A Method to Calculate Fission-Fragment Yields versus Proton and Neutron Number in the Brownian Shape-Motion Model. Application to calculations of U and Pu charge yields
We propose a method to calculate the two-dimensional (2D) fission-fragment
yield versus both proton and neutron number, with inclusion of
odd-even staggering effects in both variables. The approach is to use Brownian
shape-motion on a macroscopic-microscopic potential-energy surface which, for a
particular compound system is calculated versus four shape variables:
elongation (quadrupole moment ), neck , left nascent fragment
spheroidal deformation , right nascent fragment deformation
and two asymmetry variables, namely proton and neutron
numbers in each of the two fragments. The extension of previous models 1)
introduces a method to calculate this generalized potential-energy function and
2) allows the correlated transfer of nucleon pairs in one step, in addition to
sequential transfer. In the previous version the potential energy was
calculated as a function of and of the compound system and its shape,
including the asymmetry of the shape. We outline here how to generalize the
model from the "compound-system" model to a model where the emerging fragment
proton and neutron numbers also enter, over and above the compound system
composition
Effect of stripe order strength for the Nernst effect in La_{2-x}Sr_xCu_4 single crystals
We have precisely measured the Nernst effect in Nd-doped
LaSrCuO single crystals with controlling the strength
(stability) of the stripe order. We found that the onset temperature
, where the Nernst signal starts increasing, does not change
conspicuously in spite of Nd-doping. At low temperatures, on the other hand,
the absolute value of the Nernst signal is strongly suppressed in accordance
with the strength of the stripe order. These results imply that the fluctuation
of (charge) stripe order enhances the Nernst signal below at high
temperatures, and then the stripe order enhanced by Nd-doping suppresses the
superconducting fluctuation to reduce the Nernst signal at low temperatures. We
also observed an increase of the Nernst signal below the charge order
temperature which is observed in diffraction measurement.Comment: 3pages, 2figure
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