23,385 research outputs found
From the chiral magnetic wave to the charge dependence of elliptic flow
The quark-gluon plasma formed in heavy ion collisions contains charged chiral
fermions evolving in an external magnetic field. At finite density of electric
charge or baryon number (resulting either from nuclear stopping or from
fluctuations), the triangle anomaly induces in the plasma the Chiral Magnetic
Wave (CMW). The CMW first induces a separation of the right and left chiral
charges along the magnetic field; the resulting dipolar axial charge density in
turn induces the oppositely directed vector charge currents leading to an
electric quadrupole moment of the quark-gluon plasma. Boosted by the strong
collective flow, the electric quadrupole moment translates into the charge
dependence of the elliptic flow coefficients, so that
(at positive net charge). Using the latest quantitative simulations of the
produced magnetic field and solving the CMW equation, we make further
quantitative estimates of the produced splitting and its centrality
dependence. We compare the results with the available experimental data.Comment: Contains 12 pages, 6 figures, written as a proceeding for the talk of
Y. Burnier at the conference "P and CP-odd Effects in Hot and Dense Matter
2012" held in BN
Simulating Ability: Representing Skills in Games
Throughout the history of games, representing the abilities of the various
agents acting on behalf of the players has been a central concern. With
increasingly sophisticated games emerging, these simulations have become more
realistic, but the underlying mechanisms are still, to a large extent, of an ad
hoc nature. This paper proposes using a logistic model from psychometrics as a
unified mechanism for task resolution in simulation-oriented games
Renormalization Group Approach to Field Theory at Finite Temperature
Scalar field theory at finite temperature is investigated via an improved
renormalization group prescription which provides an effective resummation over
all possible non-overlapping higher loop graphs. Explicit analyses for the
lambda phi^4 theory are performed in d=4 Euclidean space for both low and high
temperature limits. We generate a set of coupled equations for the mass
parameter and the coupling constant from the renormalization group flow
equation. Dimensional reduction and symmetry restoration are also explored with
our improved approach.Comment: 29 pages, can include figures in the body of the text using epsf.st
UV/IR duality in noncommutative quantum field theory
We review the construction of renormalizable noncommutative euclidean
phi(4)-theories based on the UV/IR duality covariant modification of the
standard field theory, and how the formalism can be extended to scalar field
theories defined on noncommutative Minkowski space.Comment: 12 pages; v2: minor corrections, note and references added;
Contribution to proceedings of the 2nd School on "Quantum Gravity and Quantum
Geometry" session of the 9th Hellenic School on Elementary Particle Physics
and Gravity, Corfu, Greece, September 13-20 2009. To be published in General
Relativity and Gravitatio
Boson Decays to Meson and Its Uncertainties
The programming new collider with high luminosity shall provide
another useful platform to study the properties of the doubly heavy meson
in addition to the hadronic colliders as LHC and TEVATRON. Under the `New Trace
Amplitude Approach', we calculate the production of the spin-singlet and
the spin-triplet mesons through the boson decays, where
uncertainties for the production are also discussed. Our results show
KeV and
KeV, where the errors are caused by
varying and within their reasonable regions.Comment: 11 pages, 5 figures, 2 tables. To be published in Eur.Phys.J.
Managing urban flood resilience through the English planning system: insights from the ‘SuDS-face'
In academic and professional circles, ‘resilience thinking’ has emerged as the dominant paradigm in flood risk management, which emphasizes the need to plan and design cities that can absorb water and replicate natural processes more closely. In this paper, we explore how planners in England are expected to respond to the resilience agenda against the realities in practice, zoning in on the delivery of sustainable (urban) drainage systems (SuDS). Our exploration highlights that, while SuDS are being implemented, they are largely characterized by a ‘bog standard’ design. We found that there are three main institutional factors that are constraining the implementation of SuDS: the lack of legislative backing, the power afforded to private commercial interests in the neoliberalized planning process, compounded by the severe lack of resources in local authorities. What is missing at the moment is SuDS process and design that is flexible, integrated, collaborative and innovative. There are clear implications that, without the necessary institutional support, resilience thinking will remain largely aspirational, and professionals will struggle to gain traction and translate the larger flood resilience policy agenda into England's future climate-resilient places
Linear and nonlinear instabilities in rotating cylindrical Rayleigh-Bénard convection
Copyright © 2008 The American Physical SocietyLinear and nonlinear convection in a rotating annular cylinder, under experimental boundary conditions, heated from below and rotating about a vertical axis are investigated. In addition to the usual physical parameters such as the Rayleigh and Taylor number, an important geometric parameter, the ratio of the inner to outer radius, enters into the problem. For intermediate ratios, linear stability analysis reveals that there exist two countertraveling convective waves which are nonlinearly significant: a retrograde wave located near the outer sidewall and a prograde wave adjacent to the inner sidewall. Several interesting phenomena of nonlinear convection are found: (i) tempospatially modulated countertraveling waves caused by an instability of the Eckhaus-Benjamin-Feir type, (ii) destructive countertraveling waves in which the existence or disappearance of the prograde wave is determined by its relative phase to the retrograde wave, and (iii) a saddle-node-type bifurcation in which the prograde wave takes an infinite amount of time to pass over the retrograde wave
Dose-Incidence Modeling: Consequences of Linking Quantal Measures of Response to Depletion of Critical Tissue Targets
In developing mechanistic PK-PD models, incidence of toxic responses in a population has to be described in relation to measures of biologically effective dose (BED). We have developed a simple dose-incidence model that links incidence with BED for compounds that cause toxicity by depleting critical cellular target molecules. The BED in this model was the proportion of target molecule adducted by the dose of toxic compound. Our modeling approach first estimated the proportion depleted for each dose and then calculated the tolerance distribution for toxicity in relation to either administered dose or log of administered dose. We first examined cases where the mean of the tolerance distribution for toxicity occurred when a significant proportion of target had been adducted (i.e., more than half). When a normal distribution was assumed to exist for the relationship of incidence and BED, the tolerance distribution based on administered dose for these cases becomes asymmetrical and logarithmic transformations of the administered dose axis lead to a more symmetrical distribution. These linked PK-PD models for tissue reactivity, consistent with conclusions from other work for receptor binding models (Lutz et al., 2005), indicate that log normal distributions with administered dose may arise from normal distributions for BED and nonlinear kinetics between BED and administered dose. These conclusions are important for developing biologically based dose response (BBDR) models that link incidences of toxicity or other biological responses to measures of BE
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