THERMAL ION RESULTS FROM AN EXPERIMENT TO PRODUCE ARTIFICIALLY AN IONOSPHERIC HOLE - LAGOPEDO UNO

An instrument designed to determine the three-dimensional velocity and mass distribution of ions with energy per charge up to 3 eV was flown for the first time as part of the Lagopedo Uno rocket experiment, the purpose of which was to deplete artificially the ion concentration in the F layer ionosphere over Hawaii. The device measured relative ion densities and directionality; mass analysis between 1-32 amu/e was performed by using a time-of-flight technique. The depletion was achieved by detonating an explosive charge which released 10**2**7 molecules of H//2O, accompanied by lesser amounts of NO and CO//2. At the time of the explosion the densities of all ion species were reduced below the limit of detectability for 2. 5 s. The measurements of ion composition and depleted region growth pattern are in general agreement with theoretical descriptions of such events.