33,187 research outputs found
The XYZs of Charmonium at BES
This contribution reviews some recent developments in charmonium
spectroscopy, and discusses related theoretical predictions. The spectrum of
states, strong decays of states above open charm threshold, electromagnetic
transitions, and issues related to the recent discoveries of the "XYZ" states
are discussed. Contributions that BES can make to our understanding of
charmonium and related states are stressed in particular.Comment: 5 pages, 1 eps figure. Invited contribution to the International
Workshop on Tau-Charm Physics Charm2006 (5-7 June 2006, Beijing, China
Spin-other-orbit matrix elements for f sup 4 configurations
Data for spin orbit matrix elements for f to 4th power configuratio
Configuration interaction matrix elements for d sup n configurations
Configuration interaction matrix elements for weak interaction
Matrix elements of the spin-spin interactions for f sup 4 configurations
Matrix elements of spin-spin interactions for F4 electron configuration
Matrix elements of atomic interaction operators for d sup n configurations
Tabulation of matrix elements of atomic interaction operators for various configuration
Coordinate Confusion in Conformal Cosmology
A straight-forward interpretation of standard
Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmologies is that objects move
apart due to the expansion of space, and that sufficiently distant galaxies
must be receding at velocities exceeding the speed of light. Recently, however,
it has been suggested that a simple transformation into conformal coordinates
can remove superluminal recession velocities, and hence the concept of the
expansion of space should be abandoned. This work demonstrates that such
conformal transformations do not eliminate superluminal recession velocities
for open or flat matter-only FRLW cosmologies, and all possess superluminal
expansion. Hence, the attack on the concept of the expansion of space based on
this is poorly founded. This work concludes by emphasizing that the expansion
of space is perfectly valid in the general relativistic framework, however,
asking the question of whether space really expands is a futile exercise.Comment: 5 pages, accepted for publication in MNRAS Letter
A comment on a paper by Carot et al
In a recent paper Carot et al. considered carefully the definition of
cylindrical symmetry as a specialisation of the case of axial symmetry. One of
their propositions states that if there is a second Killing vector, which
together with the one generating the axial symmetry, forms the basis of a
two-dimensional Lie algebra, then the two Killing vectors must commute, thus
generating an Abelian group. In this comment a similar result, valid under
considerably weaker assumptions, is recalled: any two-dimensional Lie
transformation group which contains a one-dimensional subgroup whose orbits are
circles, must be Abelian. The method used to prove this result is extended to
apply to three-dimensional Lie transformation groups. It is shown that the
existence of a one-dimensional subgroup with closed orbits restricts the
Bianchi type of the associated Lie algebra to be I (Abelian), II, III, VII_0,
VIII or IX. The relationship between the present approach and that of the
original paper is discussed.Comment: 6 pages, Te
Universal statistics of wave functions in chaotic and disordered systems
We study a new statistics of wave functions in several chaotic and disordered
systems: the random matrix model, band random matrix model, the Lipkin model,
chaotic quantum billiard and the 1D tight-binding model. Both numerical and
analytical results show that the distribution function of a generalized Riccati
variable, defined as the ratio of components of eigenfunctions on basis states
coupled by perturbation, is universal, and has the form of Lorentzian
distribution.Comment: 6 Europhys pages, 2 Ps figures, new version to appear in Europhys.
Let
The Lerch Zeta Function II. Analytic Continuation
This is the second of four papers that study algebraic and analytic
structures associated with the Lerch zeta function. In this paper we
analytically continue it as a function of three complex variables. We that it
is well defined as a multivalued function on the manifold M equal to C^3 with
the hyperplanes corresponding to integer values of the two variables a and c
removed. We show that it becomes single valued on the maximal abelian cover of
M. We compute the monodromy functions describing the multivalued nature of this
function on M, and determine various of their properties.Comment: 29 pages, 3 figures; v2 notation changes, homotopy action on lef
Production of the h_c and h_b and Implications for Quarkonium Spectroscopy
The recent observation of the h_c is an important test of QCD calculations
and provides constraints on models of quarkonium spectroscopy. In this
contribution I discuss some of these implications and describe methods to
search for the h_c and h_b via radiative transitions and other means.Comment: Talk presented at the 1st Meeting of the APS Topical Group on
Hadronic Physics (Fermilab, Oct 24-26, 2004), 4 pages, 1 figure, uses jpconf.
References adde
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