Brian Fraser

Biography

Research interests have concentrated on the fields of magnetospheric physics and waves in space plasmas with an emphasis on ultra-low frequency (ULF) waves, often referred to as geomagnetic pulsations. The earth's magnetosphere is the region of near earth space that is threaded by magnetic field lines linked to the earth and in which ionized gas predominates over the neutral atmosphere. It is populated with ions and electrons from the earth's upper atmosphere and the impinging solar wind and by high energy particles trapped in the radiation belts. Space plasma waves of interest are hydromagnetic wave disturbance phenomena which relate to sources that may be internal or external to the magnetosphere. In particular Pc1 2 (0.2 5 Hz) pulsations are ion cyclotron plasma waves associated with the substorm which is the fundamental magnetospheric instability and internal free energy source. On the other hand, the source of lower frequency plasma waves, Pc3-4 (10-150 s period) pulsations seen at low latitudes and in the high latitude cusp region, are thought to be upstream waves external to the magnetosphere and originating in the near earth solar wind. Of interest is the generation and propagation characteristics of ion cyclotron waves and hydromagnetic waves in the earth's magnetosphere and ionosphere at high and low latitudes using both ground-based observations in Australia and Antarctica and spacecraft data provided through US collaborations and outside studies program sabbaticals. Over the period 1968-1985 research was conducted primarily on an individual basis with postgraduate student participation. Extensive studies of the magnetospheric and ionospheric propagation of Pc1 ion cyclotron waves were undertaken using networks of ground recording stations. The mid-1980's saw the beginning of the expansion of the Space Plasma Waves Group (SPWG) with the appointment of a Postdoctoral Research Associate (Dr. F.W. Menk). At this time joint research with the Australian Antarctic Division led to the installation of magnetometers at all four Australian Antarctic bases, and later at the New Zealand base. Early work concentrated on the propagation of Pc1-2 waves across the polar cap but this has considerably expanded through international cooperation to include studies of Pc3-5 waves and their relationship to the magnetospheric cusp region and upstream wave sources in the solar wind. The SPWG continued to consolidate and expand with the appointment Dr. Menk as Lecturer (1987) and Dr. H.J. Hansen as a Postdoctoral Research Associate (1987-1994).

Research Interest

Astronomical and Space Sciences, Geophysics, Mechanical Engineering