3,881 research outputs found
Quantitative Analysis of the Publishing Landscape in High-Energy Physics
World-wide collaboration in high-energy physics (HEP) is a tradition which
dates back several decades, with scientific publications mostly coauthored by
scientists from different countries. This coauthorship phenomenon makes it
difficult to identify precisely the ``share'' of each country in HEP scientific
production. One year's worth of HEP scientific articles published in
peer-reviewed journals is analysed and their authors are uniquely assigned to
countries. This method allows the first correct estimation on a ``pro rata''
basis of the share of HEP scientific publishing among several countries and
institutions. The results provide an interesting insight into the geographical
collaborative patterns of the HEP community. The HEP publishing landscape is
further analysed to provide information on the journals favoured by the HEP
community and on the geographical variation of their author bases. These
results provide quantitative input to the ongoing debate on the possible
transition of HEP publishing to an Open Access model.Comment: For a better on-screen viewing experience this paper can also be
obtained at:
http://doc.cern.ch/archive/electronic/cern/preprints/open/open-2006-065.pd
Quark fragmentation functions in a diquark model for proton and hyperon production
A simple quark-diquark model for nucleon and structure is used to
calculate leading twist light-cone fragmentation functions for a quark to
inclusively decay into P or . The parameters of the model are
determined by fitting to the known deep-inelastic structure functions of the
nucleon. When evolved from the initial to the final scale, the calculated
fragmentation functions are in remarkable agreement (for ) with those
extracted from partially inclusive and experiments at high
energies. Predictions are made, using no additional parameters, for
longitudinally and transversely polarized quarks to fragment into p or
.Comment: 15 pages, latex, figures may be obtained by writing to
hafsa%png-qau%[email protected]
ANOMALOUS GAUGE BOSON INTERACTIONS
We discuss the direct measurement of the trilinear vector boson couplings in
present and future collider experiments. The major goals of such experiments
will be the confirmation of the Standard Model (SM) predictions and the search
for signals of new physics. We review our current theoretical understanding of
anomalous trilinear gauge boson self-interactions. If the energy scale of the
new physics is TeV, these low energy anomalous couplings are expected
to be no larger than . Constraints from high precision
measurements at LEP and low energy charged and neutral current processes are
critically reviewed.Comment: 53 pages with 17 embedded figures, LaTeX, uses axodraw.sty, figures
available on request. The complete paper, is available at
ftp://phenom.physics.wisc.edu/pub/preprints/1995/madph-95-871.ps.Z or
http://phenom.physics.wisc.edu/pub/preprints/1995/madph-95-871.ps.Z Summary
of the DPF Working Subgroup on Anomalous Gauge Boson Interactions of the DPF
Long Range Planning Stud
The performance of thin NaI(Tl) scintillator plate for dark matter search
A thin (0.05cm) and wide area (5cmX5cm) NaI(Tl) scintillator was developed.
The performance of the thin NaI(Tl) plate, energy resolution, single
photoelectron energy and position sensitivity were tested. An excellent energy
resolution of 20% (FWHM) at 60keV was obtained. The single photoelectron energy
was calculated to be approximately 0.42 0.02keV. Position information in the
5cmx5cm area of the detector was also obtained by analyzing the ratio of the
number of photons collected at opposite ends of the detector. The position
resolution was obtained to be 1cm (FWHM) in the 5cmx5cm area.Comment: 10 pages. Accepted to Journal of Physical Society of Japa
Photon Structure and Quantum Fluctuation
Photon structure derives from quantum fluctuation in quantum field theory to
fermion and anti-fermion, and has been an experimentally established feature of
electrodynamics since the discovery of the positron. In hadronic physics, the
observation of factorisable photon structure is similarly a fundamental test of
the quantum field theory Quantum Chromodynamics (QCD). An overview of
measurements of hadronic photon structure in e+e- and ep interactions is
presented, and comparison made with theoretical expectation, drawing on the
essential features of photon fluctuation into quark and anti-quark in QCD.Comment: 29 pages, 15 figures, to appear in Philosophical Transactions of the
Royal Society of London (Series A: Mathematical, Physical and Engineering
Sciences
First Observation of the Hadronic Transition Υ(4S)→ηhb(1P)and New Measurement of the hb(1P) and ηb(1S) Parameters
Using a sample of 771.6×106 ΥΥ(4S) decays collected by the Belle experiment at the KEKB e+e− collider, we observe, for the first time, the transition Υ(4S)→ηhb(1P) with the branching fraction B[Υ(4S)→ηhb(1P)]=(2.18±0.11±0.18)×10−3 and we measure the hb(1P) mass Mhb(1P)=(9899.3±0.4±1.0)  MeV/c2, corresponding to the hyperfine (HF) splitting ΔMHF(1P)=(0.6±0.4±1.0)  MeV/c2. Using the transition hb(1P)→γηb(1S), we measure the ηb(1S) mass Mηb(1S)=(9400.7±1.7±1.6)  MeV/c2, corresponding to ΔMHF(1S)=(59.6±1.7±1.6)  MeV/c2, the ηb(1S) width Γηb(1S)=(8+6−5±5)  MeV/c2and the branching fraction B[hb(1P)→γηb(1S)]=(56±8±4)%
Clocking hadronization in relativistic heavy ion collisions with balance functions
A novel state of matter has been hypothesized to exist during the early stage
of relativistic heavy ion collisions, with normal hadrons not appearing until
several fm/c after the start of the reaction. To test this hypothesis,
correlations between charges and their associated anticharges are evaluated
with the use of balance functions. It is shown that late-stage hadronization is
characterized by tightly correlated charge/anticharge pairs when measured as a
function of relative rapidity.Comment: 5 pages, 3 figure
Scale Dependence of Halo Bispectrum from Non-Gaussian Initial Conditions in Cosmological N-body Simulations
We study the halo bispectrum from non-Gaussian initial conditions. Based on a
set of large -body simulations starting from initial density fields with
local type non-Gaussianity, we find that the halo bispectrum exhibits a strong
dependence on the shape and scale of Fourier space triangles near squeezed
configurations at large scales. The amplitude of the halo bispectrum roughly
scales as . The resultant scaling on the triangular shape is consistent
with that predicted by Jeong & Komatsu based on perturbation theory. We
systematically investigate this dependence with varying redshifts and halo mass
thresholds. It is shown that the dependence of the halo bispectrum is
stronger for more massive haloes at higher redshifts. This feature can be a
useful discriminator of inflation scenarios in future deep and wide galaxy
redshift surveys.Comment: 27 pages, 10 figures; revised argument in section 6, added appendix
C, JCAP accepted versio
An SU(3) model for octet baryon and meson fragmentation
The production of the octet of baryons and mesons in e^+ e^- collisions is
analysed, based on considerations of SU(3) symmetry and a simple model for
SU(3) symmetry breaking in fragmentation functions. All fragmentation
functions, D_q^h(x, Q^2), describing the fragmentation of quarks into a member
of the baryon octet (and similarly for fragmentation into members of the meson
octet) are expressed in terms of three SU(3) symmetric functions, \alpha(x,
Q^2), \beta(x, Q^2), and \gamma(x, Q^2). With the introduction of an SU(3)
breaking parameter, \lambda, the model is successful in describing
hadroproduction data at the Z pole. The fragmentation functions are then
evolved using leading order evolution equations and good fits to currently
available data at 34 GeV and at 161 GeV are obtained.Comment: 24 pages LaTeX file including 11 postscript figure file
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