Determination of the sources and sinks of N+ ions in the thermosphere

Measurements of atmospheric parameters made by the Atmosphere Explorer-C satellite are used to identify mechanisms for the production and loss of N+ ions in the ionosphere. The main source below 250 km is found to be photo-dissociative ionization of N2. Above 250 km the reaction O+(4S)+N(2D)→k1N+(3P)+O(3P) is dominant; k1 is found to be 5 −2+7 × 10−11cm³s−1. A possible minor source of N+ is the reaction O+(2P)+N2→k2N+NO where k2 = 1 −.5+1 × 10−10cm³s−1. Photoionization of N(4S) and dissociative charge exchange of He+ with N2 constitute detectable sources above 350 km. Charge exchange of N+ with O is identified as a significant sink above 300 km. The rate coefficient for this reaction is 5 −2+7 × 10−13 cm³s−1

[1]  M. Torr,et al.  Review of rate coefficients of ionic reactions determined from measurements made by the Atmosphere Explorer satellites , 1978 .

[2]  J. Frederick,et al.  On the chemistry of metastable atomic nitrogen in the F region deduced from Simultaneous satellite measurements of the 5200‐Å airglow and atmospheric composition , 1977 .

[3]  Carl A. Reber,et al.  A global thermospheric model based on mass spectrometer and incoherent scatter data MSIS, 2. Composition , 1977 .

[4]  P. Hays,et al.  The O II (7319-7330 ) Dayglow , 1977 .

[5]  M. Oppenheimer,et al.  Molecular oxygen abundances in the thermosphere from Atmosphere Explorer-C ion composition measurements , 1976 .

[6]  V. Anicich,et al.  On the reaction of N+ ions with O2 , 1976 .

[7]  C. E. Brion,et al.  Dipole excitation, ionization and fragmentation of N2 and CO in the 10-60 eV region , 1976 .

[8]  J. Hoffman,et al.  The N I (5200 Å) dayglow , 1975 .

[9]  F. Fehsenfeld,et al.  Temperature dependence of some ionospheric ion-neutral reactions from 300°–900°K , 1974 .

[10]  G. Shepherd,et al.  The visible‐airglow experiment on Atmosphere Explorer , 1973 .

[11]  A. Nier,et al.  The open‐source neutral‐mass spectrometer on Atmosphere Explorer‐C, ‐D, and ‐E , 1973 .

[12]  D. Bedo,et al.  The EUV spectrophotometer on Atmosphere Explorer. , 1973 .

[13]  J. Hoffman,et al.  The magnetic ion-mass spectrometer on Atmosphere Explorer , 1973 .

[14]  R. Moffett,et al.  Atomic nitrogen ions in the F-region , 1972 .

[15]  M. McElroy.  ATOMIC NITROGEN IONS IN THE UPPER ATMOSPHERE. , 1967 .

[16]  R. Henry.  Photoionization Cross Sections for N and O , 1966 .

[17]  S. Bauer.  Chemical processes involving helium ions and the behavior of atomic nitrogen ions in the upper atmosphere , 1966 .

[18]  D. Rapp,et al.  Total Cross Sections for Ionization and Attachment in Gases by Electron Impact. I. Positive Ionization , 1965 .

[19]  A. Hedin,et al.  Atomic nitrogen densities in the thermosphere , 1976 .

[20]  J. Hoffman,et al.  Correction [to “The N I (5200 Å) Dayglow”] , 1976 .

[21]  E. Ferguson.  Rate constants of thermal energy binary ion-molecule reactions of aeronomic interest , 1973 .

[22]  A. Dalgarno.  METASTABLE SPECIES IN THE IONOSPHERE. , 1970 .