Charles W. Smith

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The magnetic eld experiment o n A CE provides continuous measurements of the local magnetic eld in the interplanetary medium. These measurements are essential in the interpretation of simultaneous ACE observations of energetic and thermal particles distributions. The experiment consists of a pair of twin, boom-mounted, triaxial uxgate sensors which are(More)
We test a theory presented previously to account for the turbulent transport of magnetic uctuation energy in the solar wind and the related dissipation and heating of the ambient ion population. This theory accounts for the injection of magnetic energy through the damping of large-scale ow gradients such as wind shear and compression, and incorporates the(More)
We examine some implications of inertial range and dissipation range correlation and spectral analyses extracted from 33 intervals of Wind magnetic field data. When field polarity and signatures of cross helicity and magnetic helicity are examined, most of the data sets suggest some role of cyclotron-resonant dissipative processes involving thermal protons.(More)
In a previous paper we argued that the damping of obliquely propagating kinetic Alfv en waves, chieey by resonant mechanisms, was a likely explanation for the formation of the dissipation range for interplanetary magnetic eld uctuations. This suggestion was based largely on observations of the dissipation range at 1 AU as recorded by the Wind spacecraft. We(More)
Detailed morphological investigation, mechanical testing and high-speed cinematography and stroboscopic examination of desert locusts, Schistocerca gregaria, in flight show that their hind wings are adapted to deform cyclically and automatically through the wing stroke and that the deformations are subtly dependent on the wings' structure: their shape,(More)
Identifying the causal factors underlying natural selection remains a key challenge in evolutionary biology. Although the genetic basis for the plate morph evolution of three-spined stickleback (Gasterosteus aculeatus) is well described, the environmental variables that form the basis for different morphs are not understood. We measured the effects of(More)
The dissipation range of interplanetary magnetic field (IMF) fluctuations is perhaps the least-studied aspect of the IMF. This is undoubtedly due, at least in part, to the large volume of data required to perform thorough studies of the high-frequency spectrum. We examine the properties of the dissipation range at 1 AU as observed by the WIND spacecraft,(More)
We study one-point statistical properties of the induced turbulent electric field for a magnetohydrodynamic (MHD) plasma under the quasinormal approximation. Assuming exact Gaussianity for both the velocity field and the magnetic field, and different degrees of correlations between their Cartesian components, we derive the probability distribution function(More)
Magnetic reconnection in a current sheet converts magnetic energy into particle energy, a process that is important in many laboratory, space and astrophysical contexts. It is not known at present whether reconnection is fundamentally a process that can occur over an extended region in space or whether it is patchy and unpredictable in nature. Frequent(More)
Mechanisms for the deposition of heat in the lower coronal plasma are discussed, emphasizing recent attempts to reconcile the Ñuid and kinetic perspectives. Structures at magnetohydrodynamic (MHD) scales may drive a nonlinear cascade, preferentially exciting high perpendicular wavenumber Ñuctuations. Relevant dissipative kinetic processes must be identiÐed(More)