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On -Deformations in Statistical Mechanics of Bosons in D Dimensions
The Bose distribution for a gas of nonrelativistic free bosons is derived in
the framework of -deformed second quantization. Some thermodynamical
functions for such a system in D dimensions are derived. Bose-Einstein
condensation is discussed in terms of the parameters q and p as well as a
parameter which characterizes the representation space of the
oscillator algebra.Comment: 15 pages, Latex File, to be published in Symmetry and Structural
Properties of Condensed Matter, Eds. T. Lulek, B. Lulek and W. Florek (World
Scientific, Singapore, 1997
An Rotor Model for Rotational Bands of Superdeformed Nuclei
A nonrigid rotor model is developed from the two-parameter quantum algebra
. [This model presents the symmetry and
shall be referred to as the qp-rotor model.] A rotational energy formula as
well as a qp-deformation of E2 reduced transition probabilities are derived.
The qp-rotor model is applied (through fitting procedures) to twenty rotational
bands of superdeformed nuclei in the , 150 and 190 mass regions.
Systematic comparisons between the qp-rotor model and the q-rotor model of
Raychev, Roussev and Smirnov, on one hand, and a basic three-parameter model,
on the other hand, are performed on energy spectra, on dynamical moments of
inertia and on B(E2) values. The physical signification of the deformation
parameters q and p is discussed.Comment: 24 pages, Latex File, to appear in IJMP
Skyrme functional from a three-body pseudo-potential of second-order in gradients. Formalism for central terms
In one way or the other, all modern parametrizations of the nuclear energy
density functional (EDF) do not respect the exchange symmetry associated with
Pauli's principle. It has been recently shown that this practice jeopardizes
multi-reference (MR) EDF calculations by contaminating the energy with spurious
self-interactions that, for example, lead to finite steps or even divergences
when plotting it as a function of collective coordinates. As of today, the only
viable option to bypass these pathologies is to rely on EDF kernels that
enforce Pauli's principle from the outset by strictly and exactly deriving from
a genuine, i.e. density-independent, Hamilton operator.
We wish to develop the most general Skyrme-like EDF parametrization
containing linear, bilinear and trilinear terms in the density matrices with up
to two gradients, under the key constraint that it derives strictly from an
effective Hamilton operator. The most general three-body Skyrme-like
pseudo-potential containing up to two gradient operators is constructed to
generate the trilinear part. The present study is limited to central terms.
Spin-orbit and tensor will be addressed in a forthcoming paper.
(See paper for full abstract)Comment: 38 pages revtex, no figur
Aerial capsule emergency separation device Patent
Aerial capsule emergency separation device using jettisonable tower
Public Release of 2dF data from the Fornax Cluster Spectroscopic Survey
Thanks to the 2dF spectrograph on the Anglo-Australian Telescope, we have
recently completed the first stage of a complete spectroscopic survey more than
one order of magnitude larger than any previous study, measuring 7000 spectra
in a 6 sq.deg. area as part of our study of the Fornax Cluster. In this article
we describe the public release of 3600 spectra from our first field. We hope
that this public release will encourage colleagues making surveys for rare
objects to choose these fields, as much of the follow-up spectroscopy that
might be required is available from our data.Comment: To appear in the AAO Newsletter. Data online at
http://astro.ph.unimelb.edu.au/data
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