3,567 research outputs found
A modified Poisson-Boltzmann theory: Effects of co-solvent polarizability
In this paper within a field-theoretical approach taking into account
explicitly a co-solvent with a nonzero dipole and a polarizability tensor, we
derive a modified Poisson-Boltzmann equation. Applying the modified
Poisson-Boltzmann equation, we formulate a generalized Gouy-Chapman theory for
the case when an electrolyte solution is mixed with a polar co-solvent having a
large polarizability. We show that an increase of the co-solvent concentration
as well as the co-solvent polarizability lead to a significant increase of
differential capacitance at sufficiently high surface potentials of the
electrode, whereas the profile of the electrostatic potential becomes
considerably more long-ranged. On the contrary, an increase in the permanent
dipole of the co-solvent only weakly affects the differential capacitance
Particle decay in false vacuum
We revisit the problem of decay of a metastable vacuum induced by the
presence of a particle. For the bosons of the `master field' the problem is
solved in any number of dimensions in terms of the spontaneous decay rate of
the false vacuum, while for a fermion we find a closed expression for the decay
rate in (1+1) dimensions. It is shown that in the (1+1) dimensional case an
infrared problem of one-loop correction to the decay rate of a boson is
resolved due to a cancellation between soft modes of the field. We also find
the boson decay rate in the `sine-Gordon staircase' model in the limits of
strong and weak coupling.Comment: 19 pages, 2 figure
Leptonic constant of pseudoscalar B_c meson
We calculate the leptonic constant for the ground pseudoscalar state of B_c
meson in the framework of QCD-motivated potential model taking into account the
two-loop anomalous dimension for the heavy quark current in the nonrelativistic
QCD as matched with the full QCD.Comment: 6 pages, RevTeX4 file, 3 eps-figures, several references and remarks
adde
Small cosmological constant in seesaw mechanism with breaking down SUSY
The observed small value of cosmological constant can be naturally related
with the scale of breaking down supersymmetry in agreement with other
evaluations in particle physics.Comment: 12 pages, revtex4 class, 2 eps-figure
Light hadron production in decays
The article is devoted to Bc->Bs+n pi, Bc->Bs*+n pi decays with n=1, 2, 3, 4.
In the framework of factorization theorem the branching fractions of these
processes can be written as convolution of hard part, describing Bc->Bs W,
Bc->Bs* W vertices, and spectral functions, that correspond to transition of
virtual -boson into a final pi-meson system. These functions were obtained
from the fit of experimental data on -lepton decay and electron-positron
annihilation. Using different sets of Bc->Bs decay form-factors we present
branching fractions and distributions over the invariant mass of the final
pi-meson system.Comment: minor changes, some references adde
Gardner's deformations of the N=2 supersymmetric a=4-KdV equation
We prove that P.Mathieu's Open problem on constructing Gardner's deformation
for the N=2 supersymmetric a=4-Korteweg-de Vries equation has no supersymmetry
invariant solutions, whenever it is assumed that they retract to Gardner's
deformation of the scalar KdV equation under the component reduction. At the
same time, we propose a two-step scheme for the recursive production of the
integrals of motion for the N=2, a=4-SKdV. First, we find a new Gardner's
deformation of the Kaup-Boussinesq equation, which is contained in the bosonic
limit of the super-hierarchy. This yields the recurrence relation between the
Hamiltonians of the limit, whence we determine the bosonic super-Hamiltonians
of the full N=2, a=4-SKdV hierarchy. Our method is applicable towards the
solution of Gardner's deformation problems for other supersymmetric KdV-type
systems.Comment: Extended version of the talks given by A.V.K. at 8th International
conference `Symmetry in Nonlinear Mathematical Physics' (June 20-27, 2009,
Kiev, Ukraine) and 9th International workshop `Supersymmetry and Quantum
Symmetries' (July 29 - August 3, 2009, JINR, Dubna, Russia); 22 page
Variational Lie algebroids and homological evolutionary vector fields
We define Lie algebroids over infinite jet spaces and establish their
equivalent representation through homological evolutionary vector fields.Comment: Int. Workshop "Nonlinear Physics: Theory and Experiment VI"
(Gallipoli, Italy; June-July 2010). Published v3 = v2 minus typos, to appear
in: Theoret. and Mathem. Phys. (2011) Vol.167:3 (168:1), 18 page
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