197 research outputs found
The First Moments of Nucleon Generalized Parton Distributions
We extrapolate the first moments of the generalized parton distributions
using heavy baryon chiral perturbation theory. The calculation is based on the
one loop level with the finite range regularization. The description of the
lattice data is satisfactory and the extrapolated moments at physical pion mass
are consistent with the results obtained with dimensional regularization,
although the extrapolation in the momentum transfer to does show
sensitivity to form factor effects which lie outside the realm of chiral
perturbation theory. We discuss the significance of the results in the light of
modern experiments as well as QCD inspired models.Comment: 14 pages, 9 figure
The DVCS Measurement at HERA
The recent results of the studies of Deeply Virtual Compton Scattering (DVCS)
events at HERA are presented. The possibility offered by this process to gain
information about skewed parton distributions (SPD) is emphasized.Comment: Talk given at New Trends in HERA Physics 2001, Ringberg Castle,
Tegernsee, Germany, 17-22 Jun 2001, 13 pages, 10 figures, recent ZEUS data
discussed, references update
Aerial Measurement of Radioxenon Concentration off the West Coast of Vancouver Island following the Fukushima Reactor Accident
In response to the Fukushima nuclear reactor accident, on March 20th, 2011,
Natural Resources Canada conducted aerial radiation surveys over water just off
of the west coast of Vancouver Island. Dose-rate levels were found to be
consistent with background radiation, however a clear signal due to Xe-133 was
observed. Methods to extract Xe-133 count rates from the measured spectra, and
to determine the corresponding Xe-133 volumetric concentration, were developed.
The measurements indicate that Xe-133 concentrations on average lie in the
range of 30 to 70 Bq/m3.Comment: 14 pages, 5 figures, accepted for publication in Journal of
Environmental Radioactivit
Measurement of inclusive D*+- and associated dijet cross sections in photoproduction at HERA
Inclusive photoproduction of D*+- mesons has been measured for photon-proton
centre-of-mass energies in the range 130 < W < 280 GeV and a photon virtuality
Q^2 < 1 GeV^2. The data sample used corresponds to an integrated luminosity of
37 pb^-1. Total and differential cross sections as functions of the D*
transverse momentum and pseudorapidity are presented in restricted kinematical
regions and the data are compared with next-to-leading order (NLO) perturbative
QCD calculations using the "massive charm" and "massless charm" schemes. The
measured cross sections are generally above the NLO calculations, in particular
in the forward (proton) direction. The large data sample also allows the study
of dijet production associated with charm. A significant resolved as well as a
direct photon component contribute to the cross section. Leading order QCD
Monte Carlo calculations indicate that the resolved contribution arises from a
significant charm component in the photon. A massive charm NLO parton level
calculation yields lower cross sections compared to the measured results in a
kinematic region where the resolved photon contribution is significant.Comment: 32 pages including 6 figure
Measurement of event shapes in deep inelastic scattering at HERA
Inclusive event-shape variables have been measured in the current region of
the Breit frame for neutral current deep inelastic ep scattering using an
integrated luminosity of 45.0 pb^-1 collected with the ZEUS detector at HERA.
The variables studied included thrust, jet broadening and invariant jet mass.
The kinematic range covered was 10 < Q^2 < 20,480 GeV^2 and 6.10^-4 < x < 0.6,
where Q^2 is the virtuality of the exchanged boson and x is the Bjorken
variable. The Q dependence of the shape variables has been used in conjunction
with NLO perturbative calculations and the Dokshitzer-Webber non-perturbative
corrections (`power corrections') to investigate the validity of this approach.Comment: 7+25 pages, 6 figure
Angular and Current-Target Correlations in Deep Inelastic Scattering at HERA
Correlations between charged particles in deep inelastic ep scattering have
been studied in the Breit frame with the ZEUS detector at HERA using an
integrated luminosity of 6.4 pb-1. Short-range correlations are analysed in
terms of the angular separation between current-region particles within a cone
centred around the virtual photon axis. Long-range correlations between the
current and target regions have also been measured. The data support
predictions for the scaling behaviour of the angular correlations at high Q2
and for anti-correlations between the current and target regions over a large
range in Q2 and in the Bjorken scaling variable x. Analytic QCD calculations
and Monte Carlo models correctly describe the trends of the data at high Q2,
but show quantitative discrepancies. The data show differences between the
correlations in deep inelastic scattering and e+e- annihilation.Comment: 26 pages including 10 figures (submitted to Eur. J. Phys. C
Neoliberalism and the Far-Right: A Contradictory Embrace
This article examines the contradictory relationship between neoliberalism and the politics of the far-right. It seeks to identify and explain the divergence of the âeconomicâ and the social/cultural spheres under neoliberalism (notably in articulations of race and class and the âpolitics of whitenessâ) and how such developments play out in the politics of the contemporary far-right. We also seek to examine the degree to which the politics of the far-right pose problems for the consolidation and long-term stabilization of neoliberalism, through acting as a populist source of pressure on the conservative-right and tapping into sources of alienation amongst dĂ©classĂ© social layers. Finally, we locate the politics of the far-right within the broader atrophying of political representation and accountability of the neoliberal era with respect to the institutional and legal organization of neoliberalism at the international level, as most obviously highlighted in the ongoing crisis of the EU and Eurozone
A Search for the Electric Dipole Moment of the Tau-Lepton
Using the ARGUS detector at the e+e- storage ring DORIS II, we have searched
for the real and imaginary part of the electric dipole formfactor d_tau of the
tau lepton in the production of tau pairs at q^2=100 GeV^2. This is the first
direct measurement of this CP violating formfactor. We applied the method of
optimised observables which takes into account all available information on the
observed tau decay products. No evidence for CP violation was found, and we
derive the following results: Re(d_tau)=(1.6+-.9)*10^(-16) ecm and
Im(d_tau)=(-0.2+-0.8)*10^(-16) ecm, where statistical and systematic errors
have been combined.Comment: 8 pages, 5 figures (10 subfigures
- âŠ