35,261 research outputs found
Whatâs the Difference: A Study of the Nature and Extent of Racism in Rugby League
At the start of the 1993/4 season the Commission for Racial Equality (CRE) and the Professional Footballers' Association launched the 'Let's Kick Racism Out of Football' campaign which subsequently gained the support of the Football Association, the FA Premier, the Endsleigh League and the Football Trust (CRE/PFA, 1994). That campaign led to discussions between the Rugby Football League (RFL), Leeds City Council and the Commission for Racial Equality (CRE) with a view to taking action to address racism in rugby league. Some sports though have become renowned as being sites for racialist confrontations, most notably football, as recorded in Hill's (1989) account of John Barnes' experiences and Holland's (1994) work on the terraces at Newcastle, Leeds and Bolton. General impressions suggested that the position in rugby league was not as bad as in football, but racist abuse and occasional incidents of banana throwing and monkey chants have all been recorded at rugby league matches. Concern about racism at matches has also been expressed recently in the letters pages of the rugby league press and players have talked about their own experiences on television. Since we live in a racist society it would be remarkable if there was no evidence of racism in sport. Nonetheless, as the National Governing Body of the sport, the RFL recognised that this was not a reason for taking no action if it were demonstrated that there are cases of racism in rugby league. However, before embarking on direct action it was decided that information was needed on the nature and extent of racism within the game. To that end Leeds Metropolitan University was asked to survey attitudes and it was agreed that this investigation should have three main components: a) the attitudes of the clubs b) the attitudes of (black and white) players c) the attitudes of spectators At this stage we have been concerned only with the professional game, thou
Single and Many Particle Correlation Functions and Uniform Phase Bases for Strongly Correlated Systems
The need for suitable many or infinite fermion correlation functions to
describe some low dimensional strongly correlated systems is discussed. This is
linked to the need for a correlated basis, in which the ground state may be
postive definite, and in which single particle correlations may suffice. A
particular trial basis is proposed, and applied to a certain quasi-1D model.
The model is a strip of the 2D square lattice wrapped around a cylinder, and is
related to the ladder geometries, but with periodic instead of open boundary
conditions along the edges. Analysis involves a novel mean-field approach and
exact diagonalisation. The model has a paramagnetic region and a Nagaoka
ferromagnetic region. The proposed basis is well suited to the model, and
single particle correlations in it have power law decay for the paramagnet,
where the charge motion is qualitatively hard core bosonic. The mean field also
leads to a BCS-type model with single particle long range order.Comment: 23 pages, in plain tex, 12 Postscript figures included. Accepted for
publication in J.Physics : Condensed Matte
Flavor Changing Neutral Current Effects and CP Violation in the Minimal 3-3-1 Model
We investigate in detail the flavor structure of the minimal 331 model and
its implications for several flavor changing neutral current (FCNC) processes.
In this model, where the weak SU(2)_L gauge group of the Standard Model is
extended to a SU(3)_L, the by far dominant new contributions come from an
additional neutral Z' gauge boson, that can transmit FCNCs at tree-level. At
the same time, electroweak precision observables receive new contributions only
at the loop level and do not constrain the model very strongly. In our
analysis, we take into account new CP violating effects that have been
neglected in earlier analyses, and account for a general flavor structure
without reference to a certain parameterization of the new mixing matrix. We
begin by studying the bounds obtained from quantities such as Delta M_K,
epsilon_K, Delta M_{d/s} as well as sin 2 beta|_{J/psi K_S}, and go on to
explore the implications for several clean rare decay channels, namely the
decays K+->pi+ nu nu, K_L -> pi0 nu nu, B_{d/s} -> mu+ mu- and K_L -> pi0 l+l-.
We find sizeable effects in all these decays, but the most interesting quantity
turns out to be the B_s - bar B_s mixing phase beta_s, as measured in the
mixing induced CP asymmetry of B_s -> J/psi phi, which can be large. In
general, we find effects in purely hadronic channels to be larger than in
(semi-)leptonic ones, due to a suppression of the Z'-lepton couplings.Comment: 29 pages, 11 figures, Some Comments and References added, version to
appear in Phys Rev
Rare Kaon Decay K^+ --> \pi^+ \nu \bar{\nu} in SU(3)_C X SU(3)_L X U(1)_N Models
The rare kaon decay K^+ --> \pi^+ \nu \bar{\nu} is considered in the
framework of the models based on the SU(3)_C X SU(3)_L X U(1)_N (3 - 3 - 1)
gauge group. It is shown that a lower bound of the Z' mass in the 3 - 3 - 1
model with right-handed neutrinos at a value of 3 TeV is derived, while that in
the minimal version -- 1.7 TeV.Comment: 7 pages, 1 figure, late
Quartic Gauge Boson Couplings and Tree Unitarity in the SU(3)_C X SU(3)_L X U(1)_N Models
The quartic gauge boson couplings in the models are presented. We find that the couplings of four {\it
differrent} gauge bosons may have unusual Lorentz structure and the couplings
sastify the tree unitarity requirement at high energy limit.Comment: 13 pages, Latex, axodraw.st
Improved ground based sky camera for studies of enhanced spectral UV irradiance
A recent World Meteorological Organisation report discussed the importance of continued study of the effect of clouds on the solar UV radiation reaching the earths surface. The report mentions that the use of all-sky imagery offers the potential to understand and quantify cloud effects more accurately. There are an increasing number of studies investigating the enhancement of surface UV irradiance, and UV actinic flux, using automated CCD and sky cameras. This paper describes image-processing improvements and new algorithms applicable to a commercially available, relatively low cost all-sky camera (TSI-440), we use for investigating cloud enhanced spectral UV irradiance. Specifically, these include improved shadow band masking, and the addition of three new algorithms relating to cloud amount at different spatial positions and the visible brightness of clouds surrounding the sun. We also present a summary of 5-minute resolution cloud enhanced UV index and spectral UV irradiance over a 5-month period at a Southern Hemispheric sub-tropical latitude site using these new techniques, as well as how these findings relate to the current literature on this topic
The interpretation of the field angle dependence of the critical current in defect-engineered superconductors
We apply the vortex path model of critical currents to a comprehensive
analysis of contemporary data on defect-engineered superconductors, showing
that it provides a consistent and detailed interpretation of the experimental
data for a diverse range of materials. We address the question of whether
electron mass anisotropy plays a role of any consequence in determining the
form of this data and conclude that it does not. By abandoning this false
interpretation of the data, we are able to make significant progress in
understanding the real origin of the observed behavior. In particular, we are
able to explain a number of common features in the data including shoulders at
intermediate angles, a uniform response over a wide angular range and the
greater discrimination between individual defect populations at higher fields.
We also correct several misconceptions including the idea that a peak in the
angular dependence of the critical current is a necessary signature of strong
correlated pinning, and conversely that the existence of such a peak implies
the existence of correlated pinning aligned to the particular direction. The
consistency of the vortex path model with the principle of maximum entropy is
introduced.Comment: 14 pages, 7 figure
Evolution of Nuclear Shell Structure due to the Pion Exchange Potential
The evolution of nuclear shell structure is investigated for the first time
within density-dependent relativistic Hartree-Fock theory and the role of
-exchange potential is studied in detail. The energy differences between
the neutron orbits \Lrb{\nu1h_{9/2},\nu 1i_{13/2}} in the N=82 isotones and
between the proton ones \Lrb{\pi1g_{7/2},\pi1h_{11/2}} in the Z=50 isotopes
are extracted as a function of neutron excess . A kink around for
the N=82 isotones is found as an effect resulting from pion correlations. It is
shown that the inclusion of -coupling plays a central role to provide
realistic isospin dependence of the energy differences. In particular, the
tensor part of the -coupling has an important effect on the characteristic
isospin dependence observed in recent experiments.Comment: 4 pages and 4 figure
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