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Table 2 EISCAT_3D radar coverage and location requirements for different science topics, together with suggestions for complementary instruments
| Science topic | Horizontal coverage | Optimal location of radar | Number of beams; other requirements | Complementary ground-based instruments |
|---|---|---|---|---|
| Mesoscale electrodynamics and flows (including BBFs) | As wide as possible (30° elevation with all azimuths) | Within auroral oval | 20 × 20; multi-static meas. | Magnetometers, optical equipment, tomography radio receivers, SuperDARN |
| Small-scale (auroral) dynamics | 100 km in the F region, 33 km in the E region | Within the auroral oval | 30 in N-S, 10 in E-W; Multi-static meas. | Optical equipment, rockets |
| – “– | – “– | – “– | – “– | |
| Fine-scale auroral structures | 5 km in the E region, within 10–20 km from magnetic zenith in the F region | Within the auroral oval | 5–7 N-S, 1–7 E-W; multi-static meas., interferometric studies | Optical equipment, rockets |
| – “– | – “– | – “– | – “– | |
| Ion outflow (natural and heater-induced) | ~100 km curvature of field line | Within the auroral oval | N-S fan of 5–10 beams | Optical equipment, rockets |
| NEIALs (aperture synthesis imaging) | 40 km × 40 km at 700 km | Within the auroral oval | Spreading the beam in the F-A direction; plasma lines ±6 MHz | Optical equipment, rockets |
| Ionospheric irregularities | As wide as possible | Within the auroral oval | 20 × 20 | GPS scintillation measurements, rockets |
| Topside composition (O+, He+, H+) | N/A (field line tracing) | Fan, enough to cover field line curving | Optical equipment, rockets | |
| Transition region composition (NO+/O2 + vs. O+) | N/A | One; heater ion-cyclotron freq. gives additional information | Optical equipment, rockets | |
| High-energy particle events (SEPs, etc.) | As wide as possible | Oval and just equatorward of the oval | 20 × 20 | VLF, riometers, MF radar, satellites (POES, GOES, LANL, etc.), rockets |
| – “– | – “– | |||
| Atmosphere-ionosphere coupling (AGW, winds) | As wide as possible | Auroral oval and at the edge of the polar vortex | 20 × 20 | MST radar, MF radar, meteor radar, lidar, airglow imager, FPI, sounding rockets, heater (API) |
| Mesosphere-stratosphere-troposphere (MST) small-scale dynamics | As wide as possible | Location inside the polar winter vortex favourable for some questions | 20 × 20 (M), one (ST); additional low-power TX mode, dual frequency (200–1000-kHz separation) for interferometric distance determination | MST radar, MF radar, meteor radar, lidar, airglow imager, sounding rockets, heater |
| D region phenomena | As wide as possible | Oval and just equatorward of the oval | 20 × 20 | Riometer, VLF, MF radar, rockets, heater |
| PMSE, PMWE | As wide as possible | 20 × 20 | MST radar, additional ISR at higher frequency, lidar, sounding rockets, heater | |
| Meteoroids and their effects on the background (Es, PMSE, etc.), high-power mode | Fattened beam or multiple beams | Tracking mode (20 × 20 piggyback), fan for receiver beams, multi-static measurements for trajectory | Meteor radar, MST radar, optical networks | |
| Planets and asteroids | Low elevation look direction to the south, at least 25° | As far south as possible | One; arbitrary polarisation TX and RX, hydrogen maser clocks | Other IS radars, optical instruments |
| Interplanetary scintillation | Low elevation with all azimuths, particularly to the south | One; BW > 20 MHz, minimal RFI and ability to clip out individual narrow-frequency bands prior to integration over the bandwidth | Other radio receiver networks, including LOFAR and e-MERLIN | |
| Heating experiments | 20° zenith angle | Auroral oval | 10 × 10 | MST radar, airglow imager, FPI, sounding rockets |
| Heating experiments, aperture synthesis imaging | 20° zenith angle | Fatten the beam or multiple beams (10 × 10) | MST radar, airglow imager, FPI, sounding rockets | |
| Space debris monitoring and satellite tracking | 25° elevation with all azimuths | North for satellite tracking | N/A; multi-static meas. for trajectory, multiple overlapping receiver beams for interferometric angle determination, dual freq. (200–1000-kHz separation) for interferometric distance determination | |
| Meteoroid monitoring (piggyback and low-power mode) | N/A | N/A | Meteor radar, MST radar, optical networks |
