Detection and analysis of the electromagnetic pulse from hypervelocity impact plasma expansion

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Hypervelocity dust particles, including meteoroids and space debris, routinely impact spacecraft and produce plasmas that are initially dense (10^25/m^3), but rapidly expand into the surrounding vacuum. This research was the first to detect radio frequency (RF) emission associated with electromagnetic pulses (EMPs) from hypervelocity dust particle impacts in ground-based experiments. These micro particles that produced RF are 15 orders of magnitude less massive than previously observed. We find that one mechanism for EMP production is the result of the growth of the unstable Weibel mode in the plasma and that the EMP detection rate is strongly dependent on impact speed and on the electrical charge conditions at the impact surface. This mode grows from a plasma temperature anisotropy driven by the impact ionization process combined with the external electric field. Upon expansion, the Weibel mode grows, producing RF emission within nanoseconds. In particular, impacts of the fastest particles (speed > 15 km/s) occurring under spacecraft charging conditions representative of high geomagnetic activity are the most likely to produce RF emission. The sensor design and analysis that led to this discovery is discussed. This phenomenon may provide a source for unexplained RF measurements and satellite electrical anomalies.


Type of resource text
Form electronic; electronic resource; remote
Extent 1 online resource.
Publication date 2015
Issuance monographic
Language English


Associated with Johnson, Theresa Lynn
Associated with Stanford University, Department of Aeronautics and Astronautics.
Primary advisor Close, Sigrid, 1971-
Thesis advisor Close, Sigrid, 1971-
Thesis advisor Cantwell, Brian
Thesis advisor Senesky, Debbie
Advisor Cantwell, Brian
Advisor Senesky, Debbie


Genre Theses

Bibliographic information

Statement of responsibility Theresa Lynn Johnson.
Note Submitted to the Department of Aeronautics and Astronautics.
Thesis Thesis (Ph.D.)--Stanford University, 2015.
Location electronic resource

Access conditions

© 2015 by Theresa Lynn Johnson
This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).

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