Diagnosis of Nonlinear Elastic Properties of the Boundary of two Flat Rough Solids by Surface Acoustic Waves

AbstractThe paper presents the results of experimental investigations of nonlinear elastic properties of boundary between two rough surfaces of solids. The study was carried out using surface acoustic waves (SAW). We investigated the effect of the static pressure applied to the boundary of two solids and the amplitude of the probing SAW on efficiency of second harmonic generation at the border of rough surfaces. Nonlinear acoustic parameter of the second order depending on the external pressure applied to the interface was calculated. Analysis of the experimental results based on the theory of contact acoustic nonlinearity

Diagnosis of Metal Plates with Defects Using Laser Vibrometer

AbstractThe method of nonlinear laser scanning vibrometry is used for diagnostics of thin cylindrical resonators of polycrystalline aluminum alloy D16 with latent defects and residual stresses. Flexural Lamb waves are used for diagnosis. The dependence of the frequency of the resonator eigenmode on the amplitude of the flexural Lamb waves in it is detected (the effect of the fast dynamics); it indicates the presence of defects in the material of the resonator. Coordinates of defects were identified by vibromodulation technique in the resonator

CMD-3 Overview

The CMD-3 detector is installed at the VEPP-2000 e+e− collider at BINP (Novosibirsk, Russia). It is a general-purpose detector, equipped with a tracking system, two crystal (CSI and BGO) calorimeters, liquid Xe calorimeter, TOF and muon systems. The main goal of experiments at CMD-3 is a study of exclusive modes of e+e−→ hadrons at energies $\sqrt s \le$ GeV. In particular, these results provide an important input for calculation of the hadronic contribution to the muon anomalous magnetic moment. The first round of data taking was performed in 2011–2013, when about 60 1/pb were taken in the center-of-mass (c.m.) energy range from 0.32 to 2.0 GeV. Here we present a survey of results of data analysis. Between 2013 and 2016 the collider and the detector were upgraded. The data taking resumed by the end of 2016. In the first run after the upgrade about 50 1/pb were collected at the energy range between 1.28 and 2.007 GeV. We discuss the upgrade and the first preliminary results from the new data

Study of the process e+e−→KS0KL0 in the center-of-mass energy range 1004–1060 MeV with the CMD-3 detector at the VEPP-2000 e+e− collider

The e+e−→KS0KL0 cross section has been measured in the center-of-mass energy range 1004–1060 MeV at 25 energy points using 6.1×105 events with KS0→π+π− decay. The analysis is based on 5.9 pb−1 of an integrated luminosity collected with the CMD-3 detector at the VEPP-2000 e+e− collider. To obtain ϕ(1020) meson parameters the measured cross section is approximated according to the Vector Meson Dominance model as a sum of the ρ,ω,ϕ-like amplitudes and their excitations. This is the most precise measurement of the e+e−→KS0KL0 cross section with a 1.8% systematic uncertainty