A Near-Surface Burst EMP Driver Package for Prompt Gamma-Induced Sources
Abstract
This report summarizes the development of software package specifying electromagnetic pulse (EMP) drivers produced by prompt gamma rays emitted by a near-surface nuclear burst in the air. The package is designed for use with the NEMP EMP prediction computer code. This report describes improved calculations of EMP drivers arising from a point gamma source in air over ground, based on Monte Carlo simulation of the gamma transport by the specially developed SLEDGE computer code. This simulation was done for seven source gamma energies from 0.5 to 7.0 MeV. The transport was carried to a range of 25 mean free paths. Correlated sampling was used to estimate Compton electron currents more accurately. The theoretical basis of the SLEDGE code is discussed. Analytic approximations to the Monte Carlo results are described in detail, including (1) the energy deposition buildup factor (both free field and ground influenced), (2) time dependence of energy deposition as a function of both range from the burst and nearness to the ground, (3) ratio of radial Compton electron current to energy deposition rate, and (4) theta Compton electron current due to the presence of the ground. Comparisons are made with two previous EMP driver packages, with good agreement for cases where the previous packages are believed reliable.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1980
- Accession Number
- ADA091509
Entities
People
- William T. Wyatt Jr.
Organizations
- Harry Diamond Laboratories