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“Tales and Adventures”: G.A. Henty’s Union Jack and the Competitive World of Publishing for Boys in the 1880s’
In the competitive publishing environment of the late nineteenth century, writers and magazines had to distinguish themselves carefully from potential rivals. This article examines how G.A. Henty’s quality boys’ weekly, Union Jack (1880-83), attempted to secure a niche in the juvenile publishing market by deliberately distinguishing itself from other papers as a literary, imperialist and “healthy” publication. The article explores the design and marketing techniques of the magazine, its status as a fiction paper, the high calibre of its contributors, and its aggressive rhetoric in targeting an exclusively masculine audience. It argues that while Union Jack was marketed as a niche publication, it eventually failed to distinguish itself sufficiently to survive in an extremely competitive environment
Current Renormalisation Constants with an O(a)-improved Fermion Action
Using chiral Ward identities, we determine the renormalisation constants of
bilinear quark operators for the Sheikholeslami-Wohlert action lattice at
beta=6.2. The results are obtained with a high degree of accuracy. For the
vector current renormalisation constant we obtain Z_V=0.817(2)(8), where the
first error is statistical and the second is due to mass dependence of Z_V.
This is close to the perturbative value of 0.83. For the axial current
renormalisation constant we obtain Z_A = 1.045(+10 -14), significantly higher
than the value obtained in perturbation theory. This is shown to reduce the
difference between lattice estimates and the experimental values for the
pseudoscalar meson decay constants, but a significant discrepancy remains. The
ratio of pseudoscalar to scalar renormalisation constants, Z_P/Z_S, is less
well determined, but seems to be slightly lower than the perturbative value.Comment: 8 pages uuencoded compressed postscript file. Article to be submitted
to Phys.Rev.
Optimal Concentration of Light in Turbid Materials
In turbid materials it is impossible to concentrate light into a focus with
conventional optics. Recently it has been shown that the intensity on a dyed
probe inside a turbid material can be enhanced by spatially shaping the wave
front of light before it enters a turbid medium. Here we show that this
enhancement is due to concentration of light energy to a spot much smaller than
a wavelength. We focus light on a dyed probe sphere that is hidden under an
opaque layer. The light is optimally concentrated to a focus which does not
exceed the smallest focal area physically possible by more than 68%. A
comparison between the intensity enhancements of both the emission and
excitation light supports the conclusion of optimal light concentration.Comment: We corrected an ambiguous description of the focus size in our
abstract and text pointed out by an anonymous refere
The Hyperfine Splitting in Charmonium: Lattice Computations Using the Wilson and Clover Fermion Actions
We compute the hyperfine splitting on the lattice,
using both the Wilson and -improved (clover) actions for quenched quarks.
The computations are performed on a lattice at ,
using the same set of 18 gluon configurations for both fermion actions. We find
that the splitting is 1.83\err{13}{15} times larger with the clover action than
with the Wilson action, demonstrating the sensitivity of the spin-splitting to
the magnetic moment term which is present in the clover action. However, even
with the clover action the result is less than half of the physical
mass-splitting. We also compute the decay constants and
, both of which are considerably larger when computed using
the clover action than with the Wilson action. For example for the ratio
we find 0.32\err{1}{2} with the Wilson action
and with the clover action (the physical value is 0.44(2)).Comment: LaTeX file, 8 pages and two postscript figures. Southampton Preprint:
SHEP 91/92-27 Edinburgh Preprint: 92/51
Weinberg propagator of a free massive particle with an arbitrary spin from the BFV-BRST path integral
The transition amplitude is obtained for a free massive particle of arbitrary
spin by calculating the path integral in the index-spinor formulation within
the BFV-BRST approach. None renormalizations of the path integral measure were
applied. The calculation has given the Weinberg propagator written in the
index-free form with the use of index spinor. The choice of boundary conditions
on the index spinor determines holomorphic or antiholomorphic representation
for the canonical description of particle/antiparticle spin.Comment: 31 pages, Latex, version published in Class. Quantum Gra
Quenched Hadrons using Wilson and O(a)-Improved Fermion Actions at beta=6.2
We present the first study of the light hadron spectrum and decay constants
for quenched QCD using an O(a)-improved nearest-neighbour Wilson fermion action
at \beta=6.2. We compare the results with those obtained using the standard
Wilson fermion action, on the same set of 18 gauge field configurations of a
24^3 times 48 lattice. For pseudoscalar meson masses in the range 330-800 MeV,
we find no significant difference between the results for the two actions. The
scales obtained from the string tension and mesonic sector are consistent, but
differ from that derived from baryon masses. The ratio of the pseudoscalar
decay constant to the vector meson mass is roughly independent of quark mass as
observed experimentally, and in approximate agreement with the measured value.Comment: 11 page
Problems in Lattice Gauge Fixing
We review many topics and results about numeric gauge fixing in lattice QCD.Comment: 47 pages, 16 eps figures. Review article sent to IJMP
Chiral behaviour of the lattice -parameter with the Wilson and Clover Actions at
We present results for the kaon -parameter from a sample of
configurations using the Wilson action and configurations using the
SW-Clover action, on a lattice at . We compare
results obtained by renormalizing the relevant operator with different
``boosted" values of the strong coupling constant . In the case of
the SW-Clover action, we also use the operator renormalized non-perturbatively.
In the Wilson case, we observe a strong dependence of on the prescription
adopted for , contrary to the results of the Clover case which are
almost unaffected by the choice of the coupling. We also find that the matrix
element of the operator renormalized non-perturbatively has a better chiral
behaviour. This gives us our best estimate of the renormalization group
invariant -parameter, .Comment: LaTeX, 17 pages, 3 postscript figures uuencode
Gauge Invariant Smearing and Matrix Correlators using Wilson Fermions at beta=6.2
We present an investigation of gauge invariant smearing for Wilson fermions
on a lattice at . We demonstrate a smearing
algorithm that allows a substantial improvement in the determination of the
baryon spectrum obtained using propagators smeared at both source and sink, at
only a small computational cost. We investigate the matrix of correlators
constructed from local and smeared operators, and are able to expose excited
states of both the mesons and baryons.Comment: at lattice `92. 4 pages latex + 3 postscript figures. Edinburgh
preprint: 92/51
Heavy Quark Spectroscopy and Matrix Elements: A Lattice Study using the Static Approximation
We present results of a lattice analysis of the parameter, , the
decay constant , and several mass splittings using the static
approximation. Results were obtained for 60 quenched gauge configurations
computed at on a lattice size of . Light quark
propagators were calculated using the -improved Sheikholeslami-Wohlert
action. We find \Bbstat(m_b) = 0.69\er{3}{4} {\rm(stat)}\er{2}{1}
{\rm(syst)}, corresponding to \Bbstat = 1.02\er{5}{6}\er{3}{2}, and \fbstat
= 266\err{18}{20}\err{28}{27} \mev, f_{B_s}^2 B_{B_s}/f_B^2 B_B =
1.34\er{9}{8}\er{5}{3}, where a variational fitting technique was used to
extract \fbstat. For the mass splittings we obtain M_{B_s}-M_{B_d} =
87\err{15}{12}\err{6}{12} \mev, M_{\Lambda_b}-M_{B_d} =
420\errr{100}{90}\err{30}{30} \mev and M_{B^*}^2-M_B^2 =
0.281\err{15}{16}\err{40}{37} \gev^2. We compare different smearing techniques
intended to improve the signal/noise ratio. From a detailed assessment of
systematic effects we conclude that the main systematic uncertainties are
associated with the renormalisation constants relating a lattice matrix element
to its continuum counterpart. The dependence of our findings on lattice
artefacts is to be investigated in the future.Comment: 40 pages, uuencoded compressed tar file, containing one LaTeX file
and 14 postscript files (to be included with epsf). Minor change in the value
of the B parameter. Contains corrected value for the B*-B mass splitting.
Version accepted for publication in Phys. Rev.
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