First observations of SPEAR-induced artificial backscatter from CUTLASS and the EISCAT Svalbard radarsT. R. Robinson1, T. K. Yeoman1, R. S. Dhillon1, M. Lester1, E. C. Thomas1, J. D. Thornhill1, D. M. Wright1, A. P. van Eyken2, and I. W. McCrea31Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
2EISCAT Scientific Association, Box 164, 981 23 Kiruna, Sweden
3Department of Space Science and Technology, Rutherford-Appleton Laboratories, Chilton, Oxfordshire OX11 0QX, UK
Abstract. Results are presented from the first two active experimental campaigns
undertaken by the new SPEAR (Space Plasma Exploration by Active Radar)
high-power system that has recently become operational on Spitzbergen, in
the Svalbard archipelago. SPEAR's high-power beam was used to excite
artificial enhancements in the backscatter detected by the ESR (EISCAT
Svalbard Radar) parallel to the geomagnetic field, as well as coherent
backscatter detected by both of the CUTLASS (Co-operative UK Twin Located
Auroral Sounding System) coherent radars, in directions orthogonal to the
geomagnetic field. The ESR detected both enhanced ion-lines as well as
enhanced plasma-lines, that were sustained for the whole period when SPEAR
was transmitting ordinary mode radio waves, at frequencies below the maximum
F-region plasma frequency. On a number of occasions, coherent backscatter
was also observed in one or in both of the CUTLASS radars, in beams that
intersected the heated volume. Although the levels of enhanced backscatter
varied considerably in time, it appeared that ion-line, plasma-line and
coherent backscatter were all excited simultaneously, in contrast to what
has typically been reported at Tromsø, during EISCAT heater operations. A
description of the technical and operational aspects of the new SPEAR system
is also included.
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Citation: Robinson, T. R., Yeoman, T. K., Dhillon, R. S., Lester, M., Thomas, E. C., Thornhill, J. D., Wright, D. M., van Eyken, A. P., and McCrea, I. W.: First observations of SPEAR-induced artificial backscatter from CUTLASS and the EISCAT Svalbard radars, Ann. Geophys., 24, 291-309, 2006. Bibtex EndNote Reference Manager