80 research outputs found
Proton Decay from Excited States in Spherical Nuclei
Based on a single particle model which describes the time evolution of the
wave function during tunneling across a one dimensional potential barrier we
study the proton decay of Pb from excited states with non-vanishing
angular momentum . Several quantities of interest in this process like
the decay rate , the period of oscillation , the transient
time , the tunneling time and the average value of the proton
packet position are computed and compared with the WKB results.Comment: 12 pages, 4 figure
Decay Rate of Triaxially-Deformed Proton Emitters
The decay rate of a triaxially-deformed proton emitter is calculated in a
particle-rotor model, which is based on a deformed Woods-Saxon potential and
includes a deformed spin-orbit interaction. The wave function of the
ground state of the deformed proton emitter Ho is obtained
in the adiabatic limit, and a Green's function technique is used to calculate
the decay rate and branching ratio to the first excited 2 state of the
daughter nucleus. Only for values of the triaxial angle
is good agreement obtained for both the total decay rate and the 2
branching ratio.Comment: 19 pages, 4 figure
Time-dependent properties of proton decay from crossing single-particle metastable states in deformed nuclei
A dynamical study of the decay of a metastable state by quantum tunneling
through an anisotropic, non separable, two-dimensional potential barrier is
performed by the numerical solution of the time-dependent Schrodinger equation.
Initial quasi- stationary proton states are chosen in the framework of a
deformed Woods-Saxon single-particle model. The decay of two sets of states
corresponding to true and quasi levels-crossing is studied and the evolution of
their decay properties as a function of nuclear deformation is calculated
around the crossing point. The results show that the investigation of the
proton decay from metastable states in deformed nuclei can unambiguously
distinguish between the two types of crossing and determine the structure of
the nuclear states involved.Comment: 15 pages, 9 figures, submitted to Phys. Rev.
EFFECT OF HYDROTHERMAL SYNTHESIS CONDITIONS ON THE MORPHOLOGY OF ZrO 2 NANOPARTICLES
Nanoparticles based on ZrO 2 in the form of spheres, cylinders and agglomerates in the form of hollow microspheres were obtained. It is shown that the main factor influencing on the formation of nanostructures based on zirconium dioxide under hydrothermal conditions is the chemical prehistory of the starting materials. The possibility of varying the synthetic parameters to obtain a zirconia-based material with high porosity and specific surface area was shown
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