DEVELOPMENT OF A QUADRUPOLE MASS FILTER FOR ANALYSIS OF THE ATMOSPHERE IN THE 50- TO 90-KM ALTITUDE RANGE.
Abstract
A rocket-borne mass spectrometer system for sampling the earth's atmosphere in the 50- to 90-kilometer altitude interval has been designed and built. The small quadrupole mass filter used as the mass analyzer combines high sensitivity with resolution which effectively separates the peaks at masses 28, 30, and 32. During sampling, the pressure is maintained low by a zeolite adsorption pump which exhibits a speed of 100 liters per second. A uniquely designed ion source has high differential sensitivity to incoming gas relative to background gas. The ion current amplifier has a logarithmic response over the five decades from 10 to the minus 12th power amperes to 10 to the minus 7th power amperes. It is periodically calibrated during flight. This fast electrometer, having a response time of ten milliseconds, permits complete mass scans to be made every two seconds. The mass scan covers all masses below 45 with the exception of 3 and 5 to 11, inclusive. All of the electronic components are enclosed in a cylindrical compartment which is hermetically sealed and filled with dry nitrogen at atmospheric pressure. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 15, 1963
- Accession Number
- AD0822607
Entities
People
- Wilson M. Brubaker