Electromagnetic Response of a Sphere Over a Ground Plane in the Presence of Source and Conduction Currents in the Air.
Abstract
Electromagnetic effects on ground-based military systems involved in tactical nuclear warfare will be engendered by ionizing radiation, a current density of Compton-recoil electrons in the air, and a nonlinear air conductivity. Many of these systems contain conducting enclosures of one form or another that may house susceptible electronic subsystems. Consequently, the electromagnetic responses of such enclosures to tactical nuclear threats could be significant in vulnerability assessments of critical equipment. The objective of the work discussed in this report was to develop physical intuition and analytical approximations that would be useful in these assessments. Emphasis is placed on the analytical description of the salient physical phenomena that may dominate the electromagnetic response of an ideal gamma-thin obstacle subjected to a tactical nuclear threat. The charge and current on a gamma-thin conducting sphere over a ground plane were determined via the following analyses: (a) an early-time analysis wherein the ground plane is ignored and the transient air conductivity is replaced by an average value over an interval, and (b) a late-time analysis wherein the ground plane is accounted for and conduction current is assumed to dominate displacement current in the air. In both analyses, the Compton-current density and the transient air conductivity were taken to be independent of the obstacle.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1975
- Accession Number
- ADA018142
Entities
People
- John N. Bombardt Jr.
Organizations
- Harry Diamond Laboratories