Narrow Results

In this paper, with some dispersion property and Schauder’s fixed point theorem, we establish the existence of a global classical solution to a damped Vlasov–Poisson system in three-dimensional space under the assumption that the initial datum is sufficiently small and decays at infinity in phase space. Before this work, only a local solution was obtained for the three-dimensional damped Vlasov–Poisson system.

We consider contribution of the radiation damping in the quantum hydrodynamic (QHD) equations for spinless particles. We discuss possibility of obtaining corresponding nonlinear Schrödinger equation (NLSE) for the macroscopic wave function. We compare contribution of the radiation damping with weakly (or semi-) relativistic effects appearing in the second-order on $v/c$. The radiation damping appears in the third-order on $v/c$. So it might be smaller than weakly relativistic effects, but it gives damping of the Langmuir waves which can be considerable.

We explore the effects of radiation damping on electrons in a high intensity laser pulse. From classical simulations it is found that an electron can get captured in the beam focus, solely because of its radiation back reaction. This capture regime is considered in the context of an intensity-dependent mass shift of the electron. It is demonstrated that the mass shift is not just a classical effect, occurring also in the (strong field) QED theory. Using the QED process of nonlinear Compton scattering as an example, we show that the condition for the onset of electron capture is the same as the definition of the center-of-mass frame for the effective mass kinematics.

In order to study the influence of pile-soil-structure dynamic interaction caused by seismic activity on long-span cable-stayed bridges, a seismic analysis is carried out using the JiangShun bridge, which has a main span of 700m. The key dynamic parameters of the concentrated mass model are given by the M method, viscoelastic artificial boundary method and radiation damping theory. The numerical model is established by Midas/Civil, and the dynamic interaction influence law on cable-stayed bridge is analyzed. The results show that regardless of the earthquake's action being vertical or horizontal, the pile internal force response of the concentrated mass model remains the smallest among the three model types. Moreover, the pile top force response value is 30% smaller than that from the engineering simplified model. This is mainly due to radiation damping which results from the scattering of seismic waves into the infinite foundation through wave propagation.

This article reviews the recent activities carried out at CERN in terms of transverse beam splitting with proton beams. Thanks to intense experimental and theoretical activities, the recently-proposed approach of splitting beams in the horizontal phase space using stable islands moved out of the test stage and it became a mature technique of beam manipulation to perform multi-turn extraction. It is therefore timely to address the question whether stable islands can be applied to other branches of accelerator physics, in view of bringing new means of improving ring’s performance. This is the case of synchrotron light machines, where the use of stable islands could lead to new developments, and in this paper options are presented and discussed.

The infinite foundation radiation damping effect shall be fully taken into account for the purpose of simulating the earthquake response of arch dam more genuinely. This article studies the border element with consistent equivalent viscoelasticity as well as the method and technology for wave input on this border, realizes the seismic motion input of arch dam-foundation system with the stress time history in correspondence with the incident field at bottom border and free field at side border as border load. With some high arch dam in China as example, it analyzes dynamic response of arch dam-foundation system in three-direction earthquake action, compares it with calculation results of traditional massless foundation model and studies the impact of infinite foundation radiation damping upon arch-dam earthquake response.