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Department of Trade and Industry Energy Review Consultation 2006: Submission by Open University Energy & Environment Research Unit
The Open University Energy and Environment Research Unit has, since its foundation in 1986, focussed on a range of sustainable energy technologies on a variety of scales, from large to small, in the belief that a sustainable energy system will require contributions at all scales. So while we support, for example, the development of microgeneration and improvements in energy efficiency in buildings, we also believe that larger-scale projects, in particular offshore wind and city-wide combined heat and power (CHP), have a major role to play in a sustainable energy future.
This submission is in two parts:
Part One proposes a major expansion in the UK's offshore wind programme.
Part Two proposes a major expansion in Combined Heat and Power (CHP)
Heavy-light meson spectrum with and without NRQCD
Results for the spectrum of S and P-wave charmed mesons are obtained in the
quenched approximation from a tadpole-improved anisotropic gauge field action
and a D234 quark action. This is compared to the spectrum obtained from an
NRQCD charm quark and a D234 light antiquark. NRQCD results for bottom mesons
are also discussed.Comment: 4 pages, 5 figures. Lattice 2000 (Heavy Quark Physics
The charmed and bottom meson spectrum from lattice NRQCD
The mass spectrum of S and P-wave mesons containing a single heavy quark has
been computed using quenched lattice nonrelativistic QCD. Numerical results
have been obtained at first, second and third order in the heavy quark
expansion, so convergence can be discussed. The computed spectrum of charmed
and bottom mesons is compared to existing model calculations and experimental
data.Comment: 4 pages, 3 figures. To be published in the proceedings of the 4th
International Conference on Hyperons, Charm and Beauty Hadrons, Valencia,
Spain, 27-30 Jun 200
Two-Pion Decay Widths of Excited Charm Mesons
The widths for decay of the L=1 charm mesons are calculated by
describing the pion coupling to light constituents quarks by the lowest order
chiral interaction. The wavefunctions of the charm mesons are obtained as
solutions to the covariant Blankenbecler-Sugar equation. These solutions
correspond to an interaction Hamiltonian modeled as the sum of a linear scalar
confining and a screened one-gluon exchange (OGE) interaction. This interaction
induces a two-quark contribution to the amplitude for two-pion decay, which is
found to interfere destructively with the single quark amplitude. For the
currently known L=1 mesons, the total decay widths are found to be
MeV for the and MeV for the if the
axial coupling of the constituent quark is taken to be . The as yet
undiscovered spin singlet state is predicted to have a larger width of
7 - 10 MeV for decay.Comment: 20 pages, uses Feynmf Submitted to Nuclear Physics A, published
versio
The spectrum of D_s mesons from lattice QCD
The spectrum of orbitally excited mesons is computed in the continuum
limit of quenched lattice QCD. The results are consistent with the
interpretation that the narrow resonance in the channel discovered
by the BABAR Collaboration is a meson. Furthermore, within
statistical errors, the and the mass splittings are equal,
in agreement with the chiral multiplet structure predicted by heavy hadron
chiral effective theory. On our coarsest lattice we present results from the
first study of orbitally excited mesons with two flavors of dynamical
quarks, with mass slightly larger than the strange quark mass. These results
are consistent with the quenched data.Comment: 8 pages, 2 figure
Geographical interdependence, international trade and economic dynamics: the Chinese and German solar energy industries
The trajectories of the German and Chinese photovoltaic industries differ significantly yet are strongly interdependent. Germany has seen a rapid growth in market demand and a strong increase in production, especially in the less developed eastern half of the country. Chinese growth has been export driven. These contrasting trajectories reflect the roles of market creation, investment and credit and the drivers of innovation and competitiveness. Consequent differences in competiveness have generated major trade disputes
Cystic Fibrosis Foundation and European Cystic Fibrosis Society Survey of cystic fibrosis mental health care delivery
Background: Psychological morbidity in individuals with cystic fibrosis (CF) and their caregivers is common. The Cystic Fibrosis Foundation (CFF) and European Cystic Fibrosis Society (ECFS) Guidelines Committee on Mental Health sought the views of CF health care professionals concerning mental health care delivery.
Methods: An online survey which focused on the current provision and barriers to mental health care was distributed to CF health care professionals.
Results: Of the 1454 respondents, many did not have a colleague trained in mental health issues and 20% had no one on their team whose primary role was focused on assessing or treating these issues. Insufficient resources and a lack of competency were reported in relation to mental health referrals. Seventy-three percent of respondents had no experience with mental health screening. Of those who did, they utilized 48 different, validated scales.
Conclusions: These data have informed the decision-making, dissemination and implementation strategies of the Mental Health Guidelines Committee sponsored by the CFF and ECFS
Heavy-Quark Symmetry and the Electromagnetic Decays of Excited Charmed Strange Mesons
Heavy-hadron chiral perturbation theory (HHPT) is applied to the decays
of the even-parity charmed strange mesons, D_{s0}(2317) and D_{s1}(2460).
Heavy-quark spin symmetry predicts the branching fractions for the three
electromagnetic decays of these states to the ground states D_s and D_s^* in
terms of a single parameter. The resulting predictions for two of the branching
fractions are significantly higher than current upper limits from the CLEO
experiment. Leading corrections to the branching ratios from chiral loop
diagrams and spin-symmetry violating operators in the HHPT Lagrangian can
naturally account for this discrepancy. Finally the proposal that the
D_{s0}(2317) (D_{s1}(2460)) is a hadronic bound state of a D (D^*) meson and a
kaon is considered. Leading order predictions for electromagnetic branching
ratios in this molecular scenario are in very poor agreement with existing
data.Comment: 25 pages, 3 figure
Semileptonic B decays into even parity charmed mesons
By using a constituent quark model we compute the form factors relevant to
semileptonic transitions of B mesons into low-lying p-wave charmed mesons. We
evaluate the q^2 dependence of these form factors and compare them with other
model calculations. The Isgur-Wise functions tau(1/2) and tau(3/2) are also
obtained in the heavy quark limit of our results.Comment: 11 pages, 2 figure
S and P-wave heavy-light mesons in lattice NRQCD
The mass spectrum of S and P-wave mesons containing a single heavy quark is
computed in the quenched approximation, using NRQCD up to third order in the
inverse heavy quark mass expansion. Previous results found third order
contributions which are as large in magnitude as the total second order
contribution for the charmed S-wave spin splitting. The present work considers
variations such as anisotropic lattices, Landau link tadpole improvement, and a
highly-improved light quark action, and finds that the second order correction
to the charmed S-wave spin splitting is about 20% of the leading order
contribution, while the third order correction is about 20%(10%) for
D^*-D(D_s^*-D_s). Nonleading corrections are very small for the bottom meson
spectrum, and are statistically insignificant for the P-wave charmed masses.
The relative orderings among P-wave charmed and bottom mesons, and the sizes of
the mass splittings, are discussed in light of experimental data and existing
calculations.Comment: 21 pages including 6 figures, changed method of fitting correlators,
this version to be published in Phys Rev
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