We propose a generalized S-Parameter analysis for transmission lines with linear/nonlinear load terminations subject to arbitrary plane wave and port excitations. S-parameters are prevalently used to model transmission lines such as cable bundles and interconnects on printed circuit boards subject to port excitations. The conventional S-parameter approach is well suited to characterize interact...

S U M M A R Y We present a globally distributed data set of ∼400 000 frequency-dependent SH-wave traveltimes. An automated technique is used to measure teleseismic S, ScS and SS traveltimes at several periods ranging from 10 to 51 s. The targeted seismic phases are first extracted from the observed and synthetic seismograms using an automated time window algorithm. Traveltimes are then measured...

In 1964, Dashen and Frautschi published two papers in the Physical Review claiming that they calculated the neutron-proton mass difference. It was once regarded as a history-making calculation, in view of the fact that the proton and neutron had been and still are regarded as the same particle with different electromagnetic properties. However, their calculation was shown to be based on a bound...

S U M M A R Y We use cross-correlation of seismic noise recorded at stations in the San Andreas Fault Observatory at Depth (SAFOD) pilot hole to extract P and S waves and measure S-wave anisotropy on the horizontal components. The data are recorded at seven three-component stations at depths from 1857 to 2097 m in the pilot hole. In late September and early 2004 October drilling noise underneat...

The Earth’s magnetotail is an extremely complex system which—energized by the solar wind—displays many phenomena, and Alfvén waves are essential to its dynamics. While Alfvén waves were first predicted in the early 1940’s and ample observations were later made with rockets and low-altitude satellites, observational evidence of Alfvén waves in different regions of the extended magnetotail has be...

Microseismic events generate compressive waves and shear waves which can be recorded at receivers. We present a theory that shows how elastic P and S waves separately backpropagate to the original source location. These refocused P and S wavefields are free of singularities. We also demonstrate a technique that enhances the ability to image the spatial focus for each wave type using elastic wav...