118 research outputs found
The relationship between students' subject preferences and their information behaviour
Purpose
The purpose of this paper is to investigate the relationship between preferred choice of school subject and student information behaviour (IB).
Design/methodology/approach
Mixed methods were employed. In all, 152 students, teachers and librarians participated in interviews or focus groups. In total, 1,375 students, key stage 3 (11-14 years) to postgraduate, responded to a questionnaire. The research population was drawn from eight schools, two further education colleges and three universities. Insights from the literature review and the qualitative research phase led to a hypothesis which was investigated using the questionnaire: that students studying hard subjects are less likely to engage in deep IB than students studying soft subjects.
Findings
Results support the hypothesis that preferences for subjects at school affect choice of university degree. The hypothesis that a preference for hard or soft subjects affects IB is supported by results of an analysis in which like or dislike of maths/ICT is correlated with responses to the survey. Interviewees’ comments led to the proposal that academic subjects can be classified according to whether a subject helps students to acquire a “tool of the Mind” or to apply such a tool. A model suggesting how IB may differ depending on whether intellectual tools are being acquired or applied is proposed.
Practical implications
The “inner logic” of certain subjects and their pedagogies appears closely linked to IB. This should be considered when developing teaching programmes.
Originality/value
The findings offer a new perspective on subject classification and its association with IB, and a new model of the association between IB and tool acquisition or application is proposed, incorporating the perspectives of both teacher and student
Astrophysical Uncertainties in the Cosmic Ray Electron and Positron Spectrum From Annihilating Dark Matter
In recent years, a number of experiments have been conducted with the goal of
studying cosmic rays at GeV to TeV energies. This is a particularly interesting
regime from the perspective of indirect dark matter detection. To draw reliable
conclusions regarding dark matter from cosmic ray measurements, however, it is
important to first understand the propagation of cosmic rays through the
magnetic and radiation fields of the Milky Way. In this paper, we constrain the
characteristics of the cosmic ray propagation model through comparison with
observational inputs, including recent data from the CREAM experiment, and use
these constraints to estimate the corresponding uncertainties in the spectrum
of cosmic ray electrons and positrons from dark matter particles annihilating
in the halo of the Milky Way.Comment: 21 pages, 9 figure
QCD Predictions for the Transverse Energy Flow in Deep-Inelastic Scattering in the Small x HERA Regime
The distribution of transverse energy, , which accompanies
deep-inelastic electron-proton scattering at small , is predicted in the
central region away from the current jet and proton remnants. We use BFKL
dynamics, which arises from the summation of multiple gluon emissions at small
, to derive an analytic expression for the flow. One interesting
feature is an increase of the distribution with
decreasing , where . We perform a
numerical study to examine the possibility of using characteristics of the
distribution as a means of identifying BFKL dynamics at HERA.Comment: 16 pages, REVTEX 3.0, no figures. (Hardcopies of figures available on
request from Professor A.D. Martin, Department of Physics, University of
Durham, DH1 3LE, England.) Durham preprint : DTP/94/0
Pinning down the Glue in the Proton
The latest measurements of at HERA allow for a {\it combination} of
gluon and sea quark distributions at small that is significantly different
from those of existing parton sets. We perform a new global fit to
deep-inelastic and related data. We find a gluon distribution which is larger
for x \lapproxeq 0.01, and smaller for , and a flatter input sea
quark distribution than those obtained in our most recent global analysis. The
new fit also gives . We study other experimental
information available for the gluon including, in particular, the constraints
coming from fixed-target and collider prompt production data.Comment: 8 pages, LATEX, 6 figs available as .uu fil
Bottom Quark Fragmentation in Top Quark Decay
We study the fragmentation of the b quark in top decay in NLO QCD, within the
framework of perturbative fragmentation, which allows one to resum large
logarithms . We show the b-energy distribution, which
we compare with the exact result for a massive b quark.
We use data from machines in order to describe the b-quark
hadronization and make predictions for the energy spectrum of b-flavoured
hadrons in top decay. We also investigate the effect of NLL soft-gluon
resummation in the initial condition of the perturbative fragmentation function
on parton- and hadron-level energy distributions.Comment: 25 pages, 9 figure
Transverse Energy Flow at HERA
We calculate the transverse energy flow accompanying small deep-inelastic
events and compare with recent data obtained at HERA. In the central region
between the current jet and the remnants of the proton we find that BFKL
leading dynamics gives a distinctively large transverse energy
distribution, in approximate agreement with recent data.Comment: 8 LaTeX pages, 4 figures included as uuencoded postscript at the end
of the LaTeX file, Durham preprint DTP/94/3
Perturbative QCD effects and the search for a H->WW->l nu l nu signal at the Tevatron
The Tevatron experiments have recently excluded a Standard Model Higgs boson
in the mass range 160 - 170 GeV at the 95% confidence level. This result is
based on sophisticated analyses designed to maximize the ratio of signal and
background cross-sections. In this paper we study the production of a Higgs
boson of mass 160 GeV in the gg -> H -> WW -> l nu l nu channel. We choose a
set of cuts like those adopted in the experimental analysis and compare
kinematical distributions of the final state leptons computed in NNLO QCD to
lower-order calculations and to those obtained with the event generators
PYTHIA, HERWIG and MC@NLO. We also show that the distribution of the output
from an Artificial Neural Network obtained with the different tools does not
show significant differences. However, the final acceptance computed with
PYTHIA is smaller than those obtained at NNLO and with HERWIG and MC@NLO. We
also investigate the impact of the underlying event and hadronization on our
results.Comment: Extra discussion and references adde
Joint resummation in electroweak boson production
We present a phenomenological application of the joint resummation formalism
to electroweak annihilation processes at measured boson momentum Q_T. This
formalism simultaneously resums at next-to-leading logarithmic accuracy large
threshold and recoil corrections to partonic scattering. We invert the impact
parameter transform using a previously described analytic continuation
procedure. This leads to a well-defined, resummed perturbative cross section
for all nonzero Q_T, which can be compared to resummation carried out directly
in Q_T space. From the structure of the resummed expressions, we also determine
the form of nonperturbative corrections to the cross section and implement
these into our analysis. We obtain a good description of the transverse
momentum distribution of Z bosons produced at the Tevatron collider.Comment: 27 pages, LaTeX, 8 figures as eps files. Some additions to earlier
version, this version as published in Phys. Rev. D66 (2002) 01401
Recoil and Threshold Corrections in Short-distance Cross Sections
We identify and resum corrections associated with the kinematic recoil of the
hard scattering against soft-gluon emission in single-particle inclusive cross
sections. The method avoids double counting and conserves the flow of partonic
energy. It reproduces threshold resummation for high-p_T single-particle cross
sections, when recoil is neglected, and Q_T-resummation at low Q_T, when
higher-order threshold logarithms are suppressed. We exhibit explicit resummed
cross sections, accurate to next-to-leading logarithm, for electroweak
annihilation and prompt photon inclusive cross sections.Comment: minor modifications of the text, some references added. 51 pages,
LaTeX, 6 figures as eps file
Hadronic final states in deep-inelastic scattering with Sherpa
We extend the multi-purpose Monte-Carlo event generator Sherpa to include
processes in deeply inelastic lepton-nucleon scattering. Hadronic final states
in this kinematical setting are characterised by the presence of multiple
kinematical scales, which were up to now accounted for only by specific
resummations in individual kinematical regions. Using an extension of the
recently introduced method for merging truncated parton showers with
higher-order tree-level matrix elements, it is possible to obtain predictions
which are reliable in all kinematical limits. Different hadronic final states,
defined by jets or individual hadrons, in deep-inelastic scattering are
analysed and the corresponding results are compared to HERA data. The various
sources of theoretical uncertainties of the approach are discussed and
quantified. The extension to deeply inelastic processes provides the
opportunity to validate the merging of matrix elements and parton showers in
multi-scale kinematics inaccessible in other collider environments. It also
allows to use HERA data on hadronic final states in the tuning of hadronisation
models.Comment: 32 pages, 22 figure
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