Date of Award

Fall 1987

Project Type


Program or Major


Degree Name

Doctor of Philosophy


A capped hemisphere electrostatic analyzer has been developed for the purpose of performing detailed studies of charged particle distributions in space from sounding rocket platforms. This instrument employs micro channel plate detectors in conjunction with a linear resistive anode to carry out angular imaging, by resistive charge division, of particle arrivals. Two such instruments, capable of supplying 64 x 32 angle-energy positive ion distributions every $\sim1$ second were flown on two separate high latitude sounding rockets in February, 1985, from Sondre Stromfjord, Greenland. One of these two rockets featured an active ion beam experiment whereby 200 eV/q Ar$\sp{+}$ ions were injected into the ionospheric plasma from a separated sub payload in broad $(\sim60\sp\circ$ FWHM) beams directed alternately either parallel to or perpendicular to the geomagnetic field. Ion fluxes associated with beam operations were observed on the main payload out to a main/sub payload separation distance of nearly 1 km. Several distinct ion populations are identified, based on their energy/pitch angle characteristics and the existence of ion fluxes at unexpected energies and pitch angles is demonstrated and discussed in light of current understanding of these types of beam-plasma systems. The ion flux signatures of parallel versus perpendicular beam injections are compared and contrasted.