12,261 research outputs found
Scattering Dynamics of Driven Closed Billiards
We investigate the classical scattering dynamics of the driven elliptical
billiard. Two fundamental scattering mechanisms are identified and employed to
understand the rich behavior of the escape rate. A long-time algebraic decay
which can be tuned by varying the driving amplitude is established. Pulsed
escape rates and decelerated escaping particles are generic properties of the
harmonically breathing billiard. This suggests time-dependent billiards as
prototype systems to study the nonequilibrium evolution of classical ensembles
encountering a multitude of scattering processes off driven targets.Comment: 12 pages, 4 figure
The large CP phase in B(s)-anti-B(s) mixing from primary scalar unparticles
In this letter we consider the case of primary scalar unparticle
contributions to B(d,s) mixing. With particular emphasis on the impact of the
recent hint of new physics in the measurement of the B(s) mixing phase, phi(s),
we determine the allowed parameter space and impose bounds on the unparticle
couplings.Comment: 8 pages, 8 jpeg figures, using pdflatex. Typo corrected, reference
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Emotional Regulation and Interpersonal Effectiveness as Mechanisms of Change for Treatment Outcomes Within a DBT Program for Adolescents
Predictive modeling was used to identify the degree that hypothesized moderators of dialectical behavioral therapy for adolescents (DBT-A) treatment outcomes predicted anxiety and depression symptoms over time. Participants were 66 adolescents (41 girls; 25 boys) with a mean age of 15.38 years (SD = 1.51) who completed a 7-week DBT-A intervention. Analyses revealed convergent models, wherein emotion regulation and interpersonal effectiveness were substantial predictors of change in the symptoms of anxiety, F(4, 65) = 23.21, p \u3c .01, R2 = .60, and depression, F(4, 65) = 29.76, p \u3c .01, R2 = .66
Spin wave excitations: The main source of the temperature dependence of Interlayer exchange coupling in nanostructures
Quantum mechanical calculations based on an extended Heisenberg model are
compared with ferromagnetic resonance (FMR) experiments on prototype trilayer
systems Ni_7/Cu_n/Co_2/Cu(001) in order to determine and separate for the first
time quantitatively the sources of the temperature dependence of interlayer
exchange coupling. Magnon excitations are responsible for about 75% of the
reduction of the coupling strength from zero to room temperature. The remaining
25% are due to temperature effects in the effective quantum well and the
spacer/magnet interfaces.Comment: accepted for publication in PR
Chiral Condensate and Short-Time Evolution of QCD(1+1) on the Light-Cone
Chiral condensates in the trivial light-cone vacuum emerge if defined as
short-time limits of fermion propagators. In gauge theories, the necessary
inclusion of a gauge string in combination with the characteristic light-cone
infrared singularities contain the relevant non-perturbative ingredients
responsible for formation of the condensate, as demonstrated for the 't Hooft
model.Comment: 4 pages, Revtex
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