The Experts below are selected from a list of 216 Experts worldwide ranked by ideXlab platform
Alice C. Quillen - One of the best experts on this subject based on the ideXlab platform.
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Resonant chains and three-Body Resonances in the closely packed inner Uranian satellite system
Monthly Notices of the Royal Astronomical Society, 2014Co-Authors: Alice C. Quillen, Robert S. FrenchAbstract:Numerical integrations of the closely-packed inner Uranian satellite system show that variations in semi-major axes can take place simultaneously between three or four consecutive satellites. We find that the three-Body Laplace angle values are distributed unevenly and have histograms showing structure, if the angle is associated with a resonant chain, with both pairs of bodies near first-order two-Body Resonances. Estimated three-Body Resonance libration frequencies can be only an order of magnitude lower than those of first-order Resonances. Their strength arises from a small divisor from the distance to the first-order Resonances and insensitivity to eccentricity, which make up for their dependence on moon mass. Three-Body Resonances associated with low-integer Laplace angles can also be comparatively strong due to the many multiples of the angle contributed from Fourier components of the interaction terms. We attribute small coupled variations in semi-major axis, seen throughout the simulation, to ubiquitous and weak three-Body resonant couplings. We show that a system with two pairs of bodies in first-order mean-motion Resonance can be transformed to resemble the well-studied periodically-forced pendulum with the frequency of a Laplace angle serving as a perturbation frequency. We identify trios of bodies and overlapping pairs of two-Body Resonances in each trio that have particularly short estimated Lyapunov timescales.
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three Body Resonance overlap in closely spaced multiple planet systems
Monthly Notices of the Royal Astronomical Society, 2011Co-Authors: Alice C. QuillenAbstract:We compute the strengths of zeroth order (in eccentricity) three-Body Resonances for a co-planar and low-eccentricity multiple-planet system. In a numerical integration we illustrate that slowly moving Laplace angles are matched by variations in semimajor axes among three bodies with the outer two bodies moving in the same direction and the inner one moving in the opposite direction, as would be expected from the two quantities that are conserved in the three-Body Resonance. A Resonance overlap criterion is derived for the closely and uniformly spaced, equal-mass system with three-Body Resonances overlapping when interplanetary separation is less than an order unity factor times the planet mass to the one quarter power. We find that three-Body Resonances are sufficiently dense to account for wander in semimajor axis seen in numerical integrations of closely spaced systems and they are likely the cause of instability of these systems. For interplanetary separations outside the overlap region, stability time-scales significantly increase. Crudely estimated diffusion coefficients in eccentricity and semimajor axis depend on a high power of planet mass and interplanetary spacing. An exponential dependence previously fit to stability or crossing time-scales is likely due to the limited range of parameters and times possible in integration and the strong power-law dependence of the diffusion rates on these quantities.
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Three Body Resonance Overlap in Closely Spaced Multiple Planet Systems
Monthly Notices of the Royal Astronomical Society, 2011Co-Authors: Alice C. QuillenAbstract:We compute the strengths of zero-th order (in eccentricity) three-Body Resonances for a co-planar and low eccentricity multiple planet system. In a numerical integration we illustrate that slowly moving Laplace angles are matched by variations in semi-major axes among three bodies with the outer two bodies moving in the same direction and the inner one moving in the opposite direction, as would be expected from the two quantities that are conserved in the three-Body Resonance. A Resonance overlap criterion is derived for the closely and equally spaced, equal mass system with three-Body Resonances overlapping when interplanetary separation is less than an order unity factor times the planet mass to the one quarter power. We find that three-Body Resonances are sufficiently dense to account for wander in semi-major axis seen in numerical integrations of closely spaced systems and they are likely the cause of instability of these systems. For interplanetary separations outside the overlap region, stability timescales significantly increase. Crudely estimated diffusion coefficients in eccentricity and semi-major axis depend on a high power of planet mass and interplanetary spacing. An exponential dependence previously fit to stability or crossing timescales is likely due to the limited range of parameters and times possible in integration and the strong power law dependence of the diffusion rates on these quantities.
Michael S. Triantafyllou - One of the best experts on this subject based on the ideXlab platform.
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Distributed Wake-Body Resonance of a Long Flexible Cylinder in Shear Flow
Volume 5: Ocean Engineering; CFD and VIV, 2012Co-Authors: Rémi Bourguet, Michael S. Triantafyllou, Michael Tognarelli, Pierre BeynetAbstract:The fluid-structure interaction mechanisms involved in the development of narrowband and broadband vortex-induced vibrations of long flexible structures placed in non-uniform currents are investigated by means of direct numerical simulation. We consider a tensioned beam of aspect ratio 200, free to move in both the in-line and cross-flow directions, and immersed in a sheared flow at Reynolds number 330. Both narrowband and broadband multi-frequency vibrations may develop, depending on the velocity profile of the sheared oncoming current.Narrowband vibrations occur when lock-in, i.e. the synchronization between vortex shedding and structure oscillations, is limited to a single location along the span, within the high current velocity region; thus, well-defined lock-in versus non-lock-in regions are noted along the span. In contrast, we show that broadband responses, where both high and low structural wavelengths are excited, are characterized by several isolated regions of lock-in, distributed along the length. The phenomenon of distributed lock-in impacts the synchronization of the in-line and cross-flow vibrations, and the properties of the fluid-structure energy transfer, as function of time and space.Copyright © 2012 by ASME
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Wake-Body Resonance of long flexible structures is dominated by counterclockwise orbits.
Physical review letters, 2011Co-Authors: Rémi Bourguet, Yahya Modarres-sadeghi, George Em Karniadakis, Michael S. TriantafyllouAbstract:We identify a dominant mechanism in the interaction between a slender flexible structure undergoing free vibrations in sheared cross-flow and the vortices forming in its wake: energy is transferred from the fluid to the Body under a Resonance condition, defined as wake-Body frequency synchronization close to a natural frequency of the structure; this condition occurs within a well-defined region of the span, which is dominated by counterclockwise, figure-eight orbits. Clockwise orbits are associated with damping fluid forces.
Toru Sato - One of the best experts on this subject based on the ideXlab platform.
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Strange dibaryon Resonance in the K ¯ NN - π Y N system
Physical Review C, 2007Co-Authors: Yoichi Ikeda, Toru SatoAbstract:Three-Body Resonances in the $\overline{K}\mathit{NN}$ system have been studied within a framework of the $\overline{K}\mathit{NN}$-$\ensuremath{\pi}YN$ coupled-channel Faddeev equation. By solving the three-Body equation, the energy dependence of the resonant $\overline{K}N$ amplitude is fully taken into account. The $S$-matrix pole has been investigated from the eigenvalue of the kernel with the analytic continuation of the scattering amplitude on the unphysical Riemann sheet. The $\overline{K}N$ interaction is constructed from the leading order term of the chiral Lagrangian using relativistic kinematics. The $\ensuremath{\Lambda}(1405)$ Resonance is dynamically generated in this model, where the $\overline{K}N$ interaction parameters are fitted to the data of scattering length. As a result we find a three-Body Resonance of the strange dibaryon system with binding energy $B~79$ MeV and width $\ensuremath{\Gamma}~74$ MeV. The energy of the three-Body Resonance is found to be sensitive to the model of the $I=0$ $\overline{K}N$ interaction.
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Strange dibaryon and KNN-pi Sigma N coupled channel equation
arXiv: Nuclear Theory, 2006Co-Authors: Yoichi Ikeda, Toru SatoAbstract:KNN three Body Resonance has been studied by KNN-pi Sigma N coupled channel Faddeev equation. The S-matrix pole has been investigated using the analytically continued scattering amplitude on the unphysical Riemann sheet. As a result we found a three-Body Resonance of strange dibaryon system with the binding energy and width B=76MeV and \Gamma=54MeV.
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Strange dibaryon and \( \bar K \)NN-πΣN coupled channel equation
Proceedings of The IX International Conference on Hypernuclear and Strange Particle Physics, 1Co-Authors: Yoichi Ikeda, Toru SatoAbstract:\( \bar K \) NN three Body Resonance has been studied by the \( \bar K \) NN — πΣN coupled channel Faddeev equation. The S-matrix pole has been investigated using the scattering amplitude on the unphysical Riemann sheet. As a result we found a three-Body Resonance of the strange dibaryon system with a binding energy B ∼ 76MeV and a width Г ∼ 54MeV.
A. Valcarce - One of the best experts on this subject based on the ideXlab platform.
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Effect of thresholds on the width of three-Body Resonances
Physics Letters B, 2017Co-Authors: Humberto Garcilazo, A. ValcarceAbstract:Abstract It has been recently reported an intriguing theoretical result of a narrow three-Body Resonance with a large available phase space [1] . The Resonance was reported in the N Λ Λ − Ξ N N system near the Ξd threshold, having a very small width in spite of the open NΛΛ channel lying around 23 MeV below the ΞNN channel. We use first-order perturbation theory as a plausible argument to explain this behavior. We apply our result to realistic local interactions. Other systems involving several thresholds are likely to follow the same behavior.
Pierre Pillet - One of the best experts on this subject based on the ideXlab platform.
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Coherence of three-Body Förster Resonances in Rydberg atoms
Physical Review A, 2018Co-Authors: I. I. Ryabtsev, I. I. Beterov, D. B. Tretyakov, E. A. Yakshina, V. M. Entin, P. Cheinet, Pierre PilletAbstract:We have observed recently the Stark-tuned three-Body F\"orster Resonances ${\rm 3}\times nP_{3/2} (|M|)\to nS_{1/2} +(n+1)S_{1/2} +nP_{3/2} (|M^{*} |)$ at long-range interactions of a few cold Rb Rydberg atoms [D.B.Tretyakov et al., Phys. Rev. Lett. 119, 173402 (2017)]. The three-Body Resonance appears at a different dc electric field with respect to the ordinary two-Body Resonance ${\rm 2}\times nP_{3/2} (|M|)\to nS_{1/2} +(n+1)S_{1/2} $ and corresponds to a transition when the three interacting atoms change their states simultaneously (two atoms go to the $S$ states, and the third atom remains in the $P$ state but changes its moment projection), with the negligible contribution of the two-Body Resonance to the population transfer. It thus has a Borromean character and represents an effective three-Body operator, which can be used to directly control the three-Body interactions in quantum simulations and quantum gates implemented with Rydberg atoms. In this paper we theoretically investigate the coherence of such three-Body Resonances and we show that high-contrast Rabi-like population oscillations are possible for the localized Rydberg atoms in a certain spatial configuration. This paves the way to implementing three-qubit quantum gates and quantum simulations based on three-Body Rydberg interactions.
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Coherence of the Borromean three-Body Förster Resonances in Rydberg atoms
Physical Review A, 2018Co-Authors: I. I. Ryabtsev, I. I. Beterov, E. A. Yakshina, V. M. Entin, P. Cheinet, D Tretyakov, Pierre PilletAbstract:We have observed recently the Stark-tuned three-Body Förster Resonances 3 × nP 3/2 (|M |) → nS 1/2 + (n + 1)S 1/2 + nP 3/2 (|M * |) at long-range interactions of a few cold Rb Rydberg atoms [D. B. Tretyakov et al., Phys. Rev. Lett. 119, 173402 (2017)]. The three-Body Resonance appears at a different dc electric field with respect to the ordinary two-Body Resonance 2 × nP 3/2 (|M |) → nS 1/2 + (n + 1)S 1/2 and corresponds to a transition when the three interacting atoms change their states simultaneously (two atoms go to the S states, and the third atom remains in the P state but changes its moment projection), with the negligible contribution of the two-Body Resonance to the population transfer. It thus has a Borromean character and represents an effective three-Body operator, which can be used to directly control the three-Body interactions in quantum simulations and quantum gates implemented with Rydberg atoms. In this paper we theoretically investigate the coherence of such three-Body Resonances and we show that high-contrast Rabi-like population oscillations are possible for the localized Rydberg atoms in a certain spatial configuration. This paves the way to implementing three-qubit quantum gates and quantum simulations based on three-Body Rydberg interactions.
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Fast three-qubit Toffoli quantum gate based on the three-Body Förster Resonances in Rydberg atoms
Physical Review A, 2018Co-Authors: I. I. Beterov, I. I. Ryabtsev, E. A. Yakshina, V. M. Entin, P. Cheinet, Pierre Pillet, D Tretyakov, I Ashkarin, M SaffmanAbstract:We propose a scheme of fast three-qubit Toffoli quantum gate for ultracold neutral-atom qubits. The scheme is based on the Stark-tuned three-Body Förster Resonances, which we have observed in our recent experiment [D.B. Tretyakov et al., Phys. Rev. Lett. 119, 173402 (2017)]. The three-Body Resonance corresponds to a transition when the three interacting atoms change their states simultaneously, and it occurs at a different dc electric field with respect to the two-Body Förster Resonance. A combined effect of three-Body and two-Body Förster interactions in external electric and magnetic fields near the three-Body Resonance results in complex coherent behavior of the populations and phases of collective states of a three-atom system. We have found that it is possible to obtain experimental conditions suitable to implement three-qubit Toffoli gate with 98.3% fidelity and less than 3 µs duration.