Survey of PDP Data from PMG DELTA II.
Abstract
The Plasma Motor Generator (PMG) experiment was launched on 26 June 1993. The purpose was to verify the ability of the Hollow Cathode plasma contactor to provide a low impedance contact between the spacecraft and the ambient plasma. This thesis uses the data from Plasma Diagnostics Package (PDP) to study the effects of different modes on the rocket body. The electron data normally show a warm. or hot power law distribution with a characteristic energy of 10's eV. There is a consistent peak in the ion data at approx. 10 eV, which is also a peak in phase space density (distribution function). The average potential difference due to the varying bias (+65 and +0V) between rocket and ambient plasma is approx. 4 V. Subtle changes in the spectrum occur when the Far End Package (FEP) hollow cathode is switched off. Attempts were made to estimate the potential of the Delta rocket body. The variations in the data due to environmental (orbital) effects and the rapid sequencing of the PMG, made it difficult to analyze the data. The most of the measurements are interpreted as generated locally. The non-Maxwellian character of the electron distributions suggest a heating process has occurred. These processes may be due to collisions between gas or plasma einifled from the experiment and the ambient neutral oxygen, due to the high orbital energy of the system. (AN)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1995
- Accession Number
- ADA303444
Entities
People
- Chia-hwa Chi
Organizations
- Naval Postgraduate School