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The determination of shock ramp width using the noncoplanar magnetic field component

J. A. Newbury·C. T. Russell·M. Gedalin
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Abstract

We determine a simple expression for the ramp width of a collisionless fast shock, based upon the relationship between the noncoplanar and main magnetic field components. By comparing this predicted width with that measured during an observation of a shock, the shock velocity can be determined from a single spacecraft. For a range of low-Mach, low-beta bow shock observations made by the ISEE-1 and -2 spacecraft, ramp widths determined from two-spacecraft comparison and from this noncoplanar component relationship agree within 30%. When two-spacecraft measurements are not available or are inefficient, this technique provides a reasonable estimation of scale size for low-Mach shocks.

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J. A. Newbury, C. T. Russell, M. Gedalin. 1997-02-09. The determination of shock ramp width using the noncoplanar magnetic field component. https://doi.org/10.1029/97gl01977

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