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On the boundary-layer structure of high-Prandtl-number horizontal convection
Detecting atmospheric neutrino oscillations in the ATLAS detector at CERN
We discuss the possibility to study oscillations of atmospheric neutrinos in
the ATLAS experiment at CERN. Due to the large total detector mass, a
significant number of events is expected, and during the shutdown phases of the
LHC, reconstruction of these events will be possible with very good energy and
angular resolutions, and with charge identification. We argue that 500 live
days of neutrino running could be achieved, and that a total of ~160 contained
\nu_\mu events and ~360 upward going muons could be collected during this time.
Despite the low statistics, the excellent detector resolution will allow for an
unambiguous confirmation of atmospheric neutrino oscillations and for
measurements of the leading oscillation parameters. Though our detailed
simulations show that the sensitivity of ATLAS is worse than that of dedicated
neutrino experiments, we demonstrate that more sophisticated detectors, e.g. at
the ILC, could be highly competitive with upcoming superbeam experiments, and
might even give indications for the mass hierarchy and for the value of
theta-13.Comment: 8 pages, 4 figures, 2 tables, RevTeX 4; modified treatment of upward
going muons, results unchanged; matches published versio
Gluon Correlators in the Kogan-Kovner Model
The Lorentz-invariant gluon correlation functions, corresponding to scalar
and pseudo-scalar glueballs, are calculated for Kogan's and Kovner's
variational ansatz for the pure SU(N) Yang-Mills wavefunctional.
One expects that only one dynamical mass scale should be present in QCD; the
ansatz generates the expected scale for both glueballs, as well as an
additional scale for the scalar glueball. The additional mass scale must
therefore vanish, or be close to the expected one. This is shown to constrain
the nature of the phase transition in the Kogan-Kovner ansatz.Comment: 9 pages, no figure
Implementation of a Gauss convoluted Pandel PDF for track reconstruction in Neutrino Telescopes
A probability distribution function is presented which provides a realistic
description of the detection of scattered photons. The resulting probabilities
can be described analytically by means of a superposition of several special
functions. These exact expressions can be evaluated numerically only for small
distances and limited time residuals, due to computer accuracy limitations. In
this report we provide approximations for the exact expressions in different
regions of the distance-time residual space, defined by the detector geometry
and the space-time scale of an event. These approximations can be evaluated
numerically with a relative error with respect to the exact expression at the
boundaries of less than 0.001.Comment: 9 pages, 4 figures Revision 1 : extended content 12 pages, 4 figures
Accepted for publication in Astroparticle Physic
A pseudo-potential analog for zero-range photoassociation and Feshbach resonance
A zero-range approach to atom-molecule coupling is developed in analogy to
the Fermi-Huang pseudo-potential treatment of atom-atom interactions. It is
shown by explicit comparison to an exactly-solvable finite-range model that
replacing the molecular bound-state wavefunction with a regularized
delta-function can reproduce the exact scattering amplitude in the
long-wavelength limit. Using this approach we find an analytical solution to
the two-channel Feshbach resonance problem for two atoms in a spherical
harmonic trap
Impedance of a sphere oscillating in an elastic medium with and without slip
The dynamic impedance of a sphere oscillating in an elastic medium is
considered. Oestreicher's formula for the impedance of a sphere bonded to the
surrounding medium can be expressed simply in terms of three lumped impedances
associated with the displaced mass and the longitudinal and transverse waves.
If the surface of the sphere slips while the normal velocity remains
continuous, the impedance formula is modified by adjusting the definition of
the transverse impedance to include the interfacial impedance.Comment: 10 pages, 2 figure
The effect of hydrogen sulphide on ammonium bisulphite when used as an oxygen scavenger in aqueous solutions
Peer reviewedPostprin
Correlation energy in a spin polarized two dimensional electron liquid in the high density limit
We have obtained an analytic expression for the ring diagrams contribution to
the correlation energy of a two dimensional electron liquid as a function of
the uniform fractional spin polarization. Our results can be used to improve on
the interpolation formulas which represent the basic ingredient for the
constructions of modern spin-density functionals in two dimensions.Comment: 3 pages, 1 figur
The role of interactions, tunneling and harmonic confinement on the adiabatic loading of bosons in an optical lattice
We calculate entropy-temperature curves for interacting bosons in unit filled
optical lattices for both homogeneous and harmonically trapped situations, and
use them to understand how adiabatic changes in the lattice depth affect the
temperature of the system. In a translationally invariant lattice, the zero
tunneling limit facilitates a rather detailed analytic description. Unlike the
non-interacting bosonic system which is always cooled upon adiabatic loading
for low enough initial temperature, the change in the excitation spectrum
induced by interactions can lead to heating. Finite tunneling helps to reduce
this heating. Finally, we study the spatially inhomogeneous system confined in
a parabolic potential and show that the presence of the trap can significantly
reduce the final available temperature, due to the non-vanishing superfluid
component at the edge of the cloud which is present in trapped systems.Comment: 9 pages and 6 figures. Two typos in Sec.IIIA were corrected and some
references were update
Nonlinear waves of nuclear density
Nonlinear excitations of nuclear density are considered in the framework of
semiclassical nonlinear nuclear hydrodynamics. Possible types of stationary
nonlinear waves in nuclear media are analysed using Nonlinear Schroedinger
equation of fifth order and classified using a simple mechanical picture. It is
shown that a rich spectrum of nonlinear oscillations in one-dimensional nuclear
medium exist.Comment: 18 pages, 5 figure
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