2,762 research outputs found
Fermi Surface reconstruction in the CDW state of CeTe3 observed by photoemission
CeTe3 is a layered compound where an incommensurate Charge Density Wave (CDW)
opens a large gap (400 meV) in optimally nested regions of the Fermi Surface
(FS), whereas other sections with poorer nesting remain ungapped. Through
Angle-Resolved Photoemission, we identify bands backfolded according to the CDW
periodicity. They define FS pockets formed by the intersection of the original
FS and its CDW replica. Such pockets illustrate very directly the role of
nesting in the CDW formation but they could not be detected so far in a CDW
system. We address the reasons for the weak intensity of the folded bands, by
comparing different foldings coexisting in CeTe3
Informal Action—Adjudication—Rule Making: Some Recent Developments in Federal Administrative Law
Direct energy consumption of ICT hardware is only “half the story.” In order to get the “whole story,” energy consumption during the entire life cycle has to be taken into account. This chapter is a first step toward a more comprehensive picture, showing the “grey energy” (i.e., the overall energy requirements) as well as the releases (into air, water, and soil) during the entire life cycle of exemplary ICT hardware devices by applying the life cycle assessment method. The examples calculated show that a focus on direct energy consumption alone fails to take account of relevant parts of the total energy consumption of ICT hardware as well as the relevance of the production phase. As a general tendency, the production phase is more and more important the smaller (and the more energy-efficient) the devices are. When in use, a tablet computer is much more energy-efficient than a desktop computer system with its various components, so its production phase has a much greater relative importance. Accordingly, the impacts due to data transfer when using Internet services are also increasingly relevant the smaller the end-user device is, reaching up to more than 90 % of the overall impact when using a tablet computer.QC 20140825</p
Multiscale Technicolor and the Zbb-bar Vertex
We estimate the correction to the Zbb-bar vertex arising from the exchanges
of the sideways extended technicolor (ETC) boson and the flavor-diagonal ETC
boson in the multiscale walking technicolor model. The obtained result is too
large to explain the present data. However, if we introduce a new self-
interaction for the top quark to induce the top quark condensate serving as the
origin of the large top quark mass, the corrected R_b=Gamma_b/Gamma_h can be
consistent with the recent LEP data. The corresponding correction to
R_c=Gamma_c/Gamma_h is shown to be negligibly small.Comment: 9-page LaTex fil
Is it possible to formulate least action principle for dissipative systems?
A longstanding open question in classical mechanics is to formulate the least
action principle for dissipative systems. In this work, we give a general
formulation of this principle by considering a whole conservative system
including the damped moving body and its environment receiving the dissipated
energy. This composite system has the conservative Hamiltonian
where is the kinetic energy of the moving body, its potential
energy and the energy of the environment. The Lagrangian can be derived
by using the usual Legendre transformation where is the
total kinetic energy of the environment. An equivalent expression of this
Lagrangian is where is the energy dissipated by the
friction from the moving body into the environment from the beginning of the
motion. The usual variation calculus of least action leads to the correct
equation of the damped motion. We also show that this general formulation is a
natural consequence of the virtual work principle.Comment: 11 pages, no figur
Geometry and topology of two kinds of extreme Reissner-Nordstrm-anti-de Sitter black holes
Different geometrical and topological properties have been shown for two
kinds of extreme Reissner-Nordstrm-anti-de Sitter black holes. The
relationship between the geometrical properties and the intrinsic
thermodynamical properties has been made explicit.Comment: Latex, 12 pages, 4 figure
Quasinormal Modes in three-dimensional time-dependent Anti-de Sitter spacetime
The massless scalar wave propagation in the time-dependent BTZ black hole
background has been studied. It is shown that in the quasi-normal ringing both
the decay and oscillation time-scales are modified in the time-dependent
background.Comment: 8 pages and 7 figure
Global organization of metabolic fluxes in the bacterium, Escherichia coli
Cellular metabolism, the integrated interconversion of thousands of metabolic
substrates through enzyme-catalyzed biochemical reactions, is the most
investigated complex intercellular web of molecular interactions. While the
topological organization of individual reactions into metabolic networks is
increasingly well understood, the principles governing their global functional
utilization under different growth conditions pose many open questions. We
implement a flux balance analysis of the E. coli MG1655 metabolism, finding
that the network utilization is highly uneven: while most metabolic reactions
have small fluxes, the metabolism's activity is dominated by several reactions
with very high fluxes. E. coli responds to changes in growth conditions by
reorganizing the rates of selected fluxes predominantly within this high flux
backbone. The identified behavior likely represents a universal feature of
metabolic activity in all cells, with potential implications to metabolic
engineering.Comment: 15 pages 4 figure
Testing Technicolor Models in Top Quark Pair Production at High Energy Photon Colliders
We study pseudo-Goldstone boson corrections to top quark pair production
rates in technicolor models with and without topcolor at the E=0.5 teV and 1.5
TeV photon colliders. We find that, for reasonable ranges of the parameters,
the corrections are large enough to be observable, and the corrections in
models with topcolor are considerably larger than those in models without
topcolor, and they are all significantly larger than the corresponding
corrections in the minimal supersymmetric standard model (MSSM) with tan(beta)
of the order of 1. So that the two kinds of technicolor models and the MSSM
with tan(beta) of the order of 1 can be experimentally distinguished.Comment: Version for publication in Phys.Rev.D with some references and
discussions added and some typos correcte
Predictions for Pb Collisions at TeV: Comparison with Data
Predictions made in Albacete {\it et al} prior to the LHC Pb run at
TeV are compared to currently available data. Some
predictions shown here have been updated by including the same experimental
cuts as the data. Some additional predictions are also presented, especially
for quarkonia, that were provided to the experiments before the data were made
public but were too late for the original publication are also shown here.Comment: 55 pages 35 figure
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