Open AccessA mass spectrometric determination of the composition of the nighttime topside ionosphere
Author(s) -
Hoffman John H.
Publication year - 1967
Publication title -
journal of geophysical research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/jz072i007p01883
Subject(s) - ionosphere , altitude (triangle) , atmospheric sciences , ionization , ion , scale height , physics , mass spectrometry , thermosphere , chemical composition , geophysics , astrophysics , thermodynamics , geometry , mathematics , quantum mechanics
The concentrations of H + , He + and O + were determined as a function of altitude by means of a magnetic mass spectrometer flown on an Argo D‐4 rocket at local midnight on January 17, 1964, from Wallops Island, Virginia. The lower ionosphere consists primarily of O + with a transition to H + as the predominant ion at 430 km. He + never becomes the predominant species, its maximum density being 5 × 10³/cm³. The temperature calculated from scale heights of the various constituents is 700°±100°K. The neurtal hydrogen density at 350 km is calculated, assuming chemical equilibrium between H + and O + , to be 5 × 10 6 /cm³.