HR: 15:25h
AN: SA53C-06    [Abstracts]
TI: Power Thresholds of SPEAR-induced Irregularities at Very High Latitudes
AU: * Wright, D M
EM: Darren.Wright@ion.le.ac.uk
AF: Radio and Space Plasma Physics Group, Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Yeoman, T K
EM: yxo@ion.le.ac.uk
AF: Radio and Space Plasma Physics Group, Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Robinson, T R
EM: txr@ion.le.ac.uk
AF: Radio and Space Plasma Physics Group, Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Thomas, E C
EM: ect@ion.le.ac.uk
AF: Radio and Space Plasma Physics Group, Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Baddeley, L J
EM: ljb14@ion.le.ac.uk
AF: Radio and Space Plasma Physics Group, Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AU: Dhillon, R S
EM: rsd6@ion.le.ac.uk
AF: Radio and Space Plasma Physics Group, Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom
AB: SPEAR (Space Plasma Exploration by Active Radar) is a high power facility uniquely located to study the plasma physics and geophysics of the very high latitude magnetosphere and ionosphere. Recently, experiments have been undertaken to investigate the power thresholds required to excite field-aligned irregularities (FAIs). The artificially stimulated FAI act as intense targets in the fields of view of the CUTLASS HF coherent radar pair. Data derived using this artificial backscatter technique demonstrate that SPEAR effective radiated powers (ERPs) of the order of 1 MW or less are capable of initiating the formation of the FAI. This represents only 1/30th of the heating capability of SPEAR. Ionospheric hysteresis was also observed to occur during the experiments. This relates to the nature of the instability which leads to their excitation.
UR: http:www.ion.le.ac.uk/spear
DE: 2403 Active experiments
SC: SPA-Aeronomy [SA]
MN: 2007 Joint Assembly