Early Time Structuring of VHANES: Preliminary Results
Abstract
The stability of the debris shell of a nuclear burst at altitudes above 400 km is investigated. A set of relatively simple expressions are derived to estimate the effective gravitational acceleration associated with the deceleration of the shell (by mass pick-up and magnetic field sweep-up) and the curvature of the magnetic field. This stability analysis is based on recently developed kinetic theory. In particular, the turn-on conditions for the unmagnetized ion Rayleigh-Taylor instability are derived for both the fluid and kinetic regimes, as well as the finite Larmor radius stabilization criterion for the magnetized ion Rayleigh-Taylor instability. We apply these results to 1 MT bursts at altitudes h = 400 km, 1,000 km, and 10,000 km. We find the burst at 400 km is stable to the unmagnetized ion Rayleigh-Taylor instability; the burst at 1,000 km is marginally unstable to the kinetic instability; and the burst at 10,000 km is strongly unstable to both the kinetic and fluid instabilities. A critical parameter in determining the stability properties of the debris shell is the density gradient scale length (or shell thickness).
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 15, 1990
- Accession Number
- ADA225477
Entities
People
- Joseph D. Huba
Organizations
- United States Naval Research Laboratory