Shock wave

About: Shock wave is a research topic. Over the lifetime, 36184 publications have been published within this topic receiving 635848 citations. The topic is also known as: Shock waves & shockwave.

Light scattering measurements of the repetitive supersonic implosion of a sonoluminescing bubble.

Abstract: Light scattering is used to measure the dynamics of the repetitive collapse of a sonoluminescing bubble of gas trapped in water. It is found that the surface of the bubble is collapsing with a supersonic velocity at about the time of light emision which in turn precedes the minimum bubble radius by about 0.03% of the period of the acoustic drive. These observations suggest that the shedding of an imploding shock mediates between the bubble collapse and light emission

Shock waves in a dusty gas

Abstract: The plane steady decelerated flow of a dust-gas mixture is analysed in an approximate manner. The problem, which has a five-parameter family of solutions, is reduced to a form such that the analysis can be completed by the integration of a first-order non-linear differential equation and a quadrature. A few integral curves are given and the characterizing features of the flow field are discussed.

Plasma waves associated with energetic particles streaming into the solar wind from the earth's bow shock. Progress report for period ending jul 80

Abstract: In the upstream solar wind, three dominant types of plasma waves are observed associated with energetic particle streams coming from the earth's bow shock: ion-acoustic waves, electron plasma oscillations, and whistler-mode waves. The ion-acoustic waves occur simultaneously with either ion beams or a dispersed ion population in the energy range from approximately 0.5 to greater than 45 keV. These short-wavelength electrostatic waves are very impulsive and the peak amplitudes increase with increasing ion flux and at spatial gradients in the energetic ion densities. The electon plasma oscillations are long-wavelength nearly monochromatic electrostatic wave which are closely correlated with the flux of low energy electrons, especially in the 0.2 - 1.5 keV range. In the presence of only enhanced electron fluxes, the average amplitudes of the electron plasma oscillations approach the peak amplitudes. (Author)

Radio signature of cosmological structure formation shocks

Abstract: In the course of the formation of cosmological structures, large shock waves are generated in the intracluster medium (ICM). In analogy to processes in supernova remnants, these shock waves may generate a significant population of relativistic electrons which, in turn, produce observable synchrotron emission. The extended radio relics found at the periphery of several clusters and possibly also a fraction of radio halo emission may have this origin. Here, we derive an analytic expression for (i) the total radio power in the downstream region of a cosmological shock wave, and (ii) the width of the radio-emitting region. These expressions predict a spectral slope close to -1 for strong shocks. Moderate shocks, such as those produced . in mergers between clusters of galaxies, lead to a somewhat steeper spectrum. Moreover, we predict an upper limit for the radio power of cosmological shocks. Comparing our results to the radio relics in Abell 115, 2256 and 3667, we conclude that the magnetic field in these relics is typically at a level of 0.1 μG. Magnetic fields in the ICM are presumably generated by the shocks themselves; this allows us to calculate the radio emission as a function of the cluster temperature. The resulting emissions agree very well with the radio power-temperature relation found for cluster haloes. Finally, we show that cosmic accretion shocks generate less radio emission than merger shock waves. The latter may, however, be detected with upcoming radio telescopes.