The beam-beam effects of the PEP-II as an asymmetric collider are studied with strong-strong simulations using a newly developed particle-in-cell (PIC) code[1]. The simulated luminosity agrees with the measured one within 10% in a large range of the beam currents. The spectra of coherent dipole oscillation are simulated with and without the transparency symmetry. The simulated tune shift of the...

Analytical formulas are derived for the average intensity, the root-mean-square (rms) angular width, and the M2-factor of Laguerre-Gaussian correlated Schell-model (LGCSM) beam propagating in non-Kolmogorov turbulence. The influence of the beam and turbulence parameters on the LGCSM beam is numerically calculated. It is shown that the quality of the LGCSM beam can be improved by choo...

This paper presents a parametric study of steel I- beam with stepped flanges by using finite element analysis. Stepped flange beam is used in structures to decrease the negative bending moments near interior supports that causes failure due to buckling. Steps in the cross section can be achieved by adding cover plates to the beam flanges, changing the size of the hot rolled section, or changing...

in this paper, a crack localization method for euler-bernoulli beams via an efficient static data based indicator is proposed. the crack in beams is simulated here using a triangular variation in the stiffness. static responses of a beam are obtained by the finite element modeling. in order to reduce the computational cost of damage detection method, the beam deflection is fitted through a poly...

We report on a novel diagnostics instrument for in-situ imaging and measurements of X-ray beam parameters in real-time. The instrument is based on the robust and simple idea of a pinhole camera that collects the weakly scattered radiation from a thin sheet of a low-Z material placed in the X-ray beam at an acute angle. We demonstrate how by recording the scattered radiation with an appropriate ...

This is a summary of a panel discussion following a presentation on beam-beam simulation codes [1]. It reflects the main issues raised and considered important during the discussion by the panel members and the audience. Due to the limited time available for the formal discussion, some relevant deliberations during informal discussions mainly between and with panel members have been included as...

We study experimentally and theoretically a beam splitter setup for guided atomic matter waves. The matter wave is a guided atom laser that can be tuned from quasimonomode to a regime where many transverse modes are populated, and propagates in a horizontal dipole beam until it crosses another horizontal beam at 45°. We show that depending on the parameters of this X configuration, the atoms ca...

In this paper, an overview of the calculation of synthetic seismograms using the Gaussian beam method is presented accompanied by some representative applications and new extensions of the method. Since caustics are a frequent occurrence in seismic wave propagation, modifications to ray theory are often necessary. In the Gaussian beam method, a summation of paraxial Gaussian beams is used to de...

The theoretical description of the beam-beam interaction presented here takes into account all the important features of the beam-beam phenomenon: the nonlinear beam-beam force and its dependence on both transverse coordinates, damping of the oscillations, presence of noise in the particle motion, in particular the quantum noise in its synchrotron radiation, actual machine functions, layout and...