202 research outputs found
An error tolerant memory aid for reduced cognitive load in number copying tasks
Number copying tasks are still common despite increased digitalization of services. Number copying tasks are cognitively and visually demanding, errors are easily introduced and the process is often perceived as laborious. This study proposes an alternative scheme based on dictionary coding that reduces the cognitive load on the user by a factor of five. The strategy has several levels of error detection and error correction characteristics and is easy to implemen
Dielectric and conductivity relaxation in mixtures of glycerol with LiCl
We report a thorough dielectric characterization of the alpha relaxation of
glass forming glycerol with varying additions of LiCl. Nine salt concentrations
from 0.1 - 20 mol% are investigated in a frequency range of 20 Hz - 3 GHz and
analyzed in the dielectric loss and modulus representation. Information on the
dc conductivity, the dielectric relaxation time (from the loss) and the
conductivity relaxation time (from the modulus) is provided. Overall, with
increasing ion concentration, a transition from reorientationally to
translationally dominated behavior is observed and the translational ion
dynamics and the dipolar reorientational dynamics become successively coupled.
This gives rise to the prospect that by adding ions to dipolar glass formers,
dielectric spectroscopy may directly couple to the translational degrees of
freedom determining the glass transition, even in frequency regimes where
usually strong decoupling is observed.Comment: 8 pages, 7 figure
Mass spectrum of the axial-vector hidden charmed and hidden bottom tetraquark states
In this article, we perform a systematic study of the mass spectrum of the
axial-vector hidden charmed and hidden bottom tetraquark states using the QCD
sum rules, and identify the as an axial-vector tetraquark state
tentatively.Comment: 24 pages, 38 figures, slight revisio
A study of pseudoscalar states produced centrally in pp interactions at 450 GeV/c
A study has been made of pseudoscalar mesons produced centrally in pp
interactions. The results show that the eta and etaprime appear to have a
similar production mechanism which differs from that of the pi0. The production
properties of the eta and etaprime are not consistent with what is expected
from double Pomeron exchange. In addition the production mechanism for the eta
and etaprime is such that the production cross section are greatest when the
azimuthal angle between the pT vectors of the two protons is 90 degrees.Comment: 11 pages, Latex, 3 Figure
A study of the centrally produced phiphi system in pp interactions at 450 GeV/c
The reaction pp to pfps(K+K-K+K-) in which the K+K-K+K- system is centrally
produced has been studied at 450 GeV/c. Phi phi production has been found to
dominate this reaction and is compatible with being produced by double Pomeron
exchange. An angular analysis of the phi phi system favours JPC = 2++ and its
dPT dependence is similar to that observed for glueball candidates.Comment: 11 pages, Latex, 4 Figure
Heavy quarkonium: progress, puzzles, and opportunities
A golden age for heavy quarkonium physics dawned a decade ago, initiated by
the confluence of exciting advances in quantum chromodynamics (QCD) and an
explosion of related experimental activity. The early years of this period were
chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in
2004, which presented a comprehensive review of the status of the field at that
time and provided specific recommendations for further progress. However, the
broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles
could only be partially anticipated. Since the release of the YR, the BESII
program concluded only to give birth to BESIII; the -factories and CLEO-c
flourished; quarkonium production and polarization measurements at HERA and the
Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the
deconfinement regime. All these experiments leave legacies of quality,
precision, and unsolved mysteries for quarkonium physics, and therefore beg for
continuing investigations. The plethora of newly-found quarkonium-like states
unleashed a flood of theoretical investigations into new forms of matter such
as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the
spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b},
and b\bar{c} bound states have been shown to validate some theoretical
approaches to QCD and highlight lack of quantitative success for others. The
intriguing details of quarkonium suppression in heavy-ion collisions that have
emerged from RHIC have elevated the importance of separating hot- and
cold-nuclear-matter effects in quark-gluon plasma studies. This review
systematically addresses all these matters and concludes by prioritizing
directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K.
Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D.
Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A.
Petrov, P. Robbe, A. Vair
corrections to the polar angle dependence of the longitudinal spin-spin correlation asymmetry in
We provide analytical results for the corrections to the polar
angle dependence of the longitudinal spin-spin correlation asymmetry in
. For top quark pair production the
corrections to the longitudinal spin-spin asymmetry are strongly polar angle
dependent and can amount up to in the -range from above
threshold up to GeV. The radiative corrections
to the correlation asymmetry are below in the forward direction where the
cross section is largest. In the case the
corrections reduce the asymmetry value from its value of to
approximately for -values around the peak and are practically
independent of the value of the polar angle theta. This reduction can be traced
to finite anomalous contributions from residual mass effects which survive the
limit. We discuss the role of the anomalous contributions and the
pattern of how they contribute to spin-flip and non-flip terms.Comment: 32 pages written in LaTeX, including 8 encapsulated postscript
figures and 2 tables; v2: corrections according to the erratu
A study of the centrally produced 4pi channel in pp interactions at 450 GeV/c
The reaction pp -> pf (pi+pi-pi+pi-) ps has been studied at 450 GeV/c in an
experiment designed to search for gluonic states. A spin analysis has been
performed and the dPT filter applied. In addition to the well known f1(1285)
there is evidence for two JPC=2-+ states called the eta2(1620) and eta2(1875)
and a broad scalar called the f0(2000). The production of these states as a
function of the dPT kinematical filter shows the behaviour expected for qqbar
states. In contrast, there is evidence for two states at 1.45 GeV and at 1.9
GeV which do not show the behaviour observed for qqbar states.Comment: 14 pages, Latex, 3 Figure
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