68,053 research outputs found
Nonconical theory of flow past slender wing bodies with leading-edge separation
Nonconical theory of flow past slender wing bodies with leading edge separatio
Nonlinear lift and pressure distribution of slender conical bodies with strakes at low speeds
Nonlinear lift and pressure distribution of slender conical bodies with strakes at low spee
Modeling the IDV emissions of the BL Lac Objects with a Langevin type stochastic differential equation
In this paper, we introduce a simplified model for explaining the
observations of the optical intraday variability (IDV) of the BL Lac Objects.
We assume that the source of the IDV are the stochastic oscillations of an
accretion disk around a supermassive black hole. The Stochastic Fluctuations on
the vertical direction of the accretion disk are described by using a Langevin
type equation with a damping term and a random, white noise type force.
Furthermore, the preliminary numerical simulation results are presented, which
are based on the numerical analysis of the Langevin stochastic differential
equation.Comment: 4 pages, 4 figures, accepted for publication in J. Astrophys. Ast
Suppression of low-energy Andreev states by a supercurrent in YBa_2Cu_3O_7-delta
We report a coherence-length scale phenomenon related to how the high-Tc
order parameter (OP) evolves under a directly-applied supercurrent. Scanning
tunneling spectroscopy was performed on current-carrying YBa_2Cu_3O_7-delta
thin-film strips at 4.2K. At current levels well below the theoretical
depairing limit, the low-energy Andreev states are suppressed by the
supercurrent, while the gap-like structures remain unchanged. We rule out the
likelihood of various extrinsic effects, and propose instead a model based on
phase fluctuations in the d-wave BTK formalism to explain the suppression. Our
results suggest that a supercurrent could weaken the local phase coherence
while preserving the pairing amplitude. Other possible scenarios which may
cause the observed phenomenon are also discussed.Comment: 6 pages, 4 figures, to appear in Physical Review
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