2010 Workshop:RAX plasma turbulence science
From CedarWiki
Mid-to-high latitude ionospheric irregularities and experimental opportunities with the Radio Aurora Explorer satellite mission
Location, Date/Time and Duration
2 hours
Conveners
Workshop Categories
Altitudes: IT - Latitudes: global - Inst/Model: radar - Other: satellite
Format of the Workshop
Short Presentations
Estimated attendance
30
Speakers:
Meers Oppenheim (Boston University) Dave Hysell (Cornell University) Roger Varney (Cornell University) J.P. St.Maurice, (University of Saskatchewan) Phil Ericson (MIT Haystack) Hasan Bahcivan (SRI International) James Cutler (University of Michigan)
Conflicts with other workshops or Requested Specific Days
Special technology requests
Description
Small-scale (m to 10s m) ionospheric irregularities are plasma waves that are excited between the altitudes of ~80-500 km under strong electric fields and currents with magnetospheric or neutral wind origin. Understanding the microphysics of the irregularities is important to predict their occurrence for a set of geophysical conditions, to assess the effect on the transionospheric communication and navigation signals, and to quantify the contribution to the energetics of the upper atmosphere.
The Radio Aurora Explorer (RAX) satellite mission, currently planned for launch in 2010, is a ground-to-space bistatic radar experiment to measure meter-scale magnetic field-aligned irregularities that are not observable from the ground or observable but with poor resolution. Furthermore, since the irregularity volume is illuminated by an incoherent scatter radar (ISR), the incoherently scattered signals back to the ISR can be used to measure the plasma parameters and electric field in the scattering volume. This last capability enables aspect sensitivity measurements of the irregularities by probing the same volume from different angles. The UHF radar receiver on RAX is capable of receiving signals from PFISR, RISR, ESR, Millstone, and Arecibo incoherent scatter radars, providing experimental capability for observations of ionospheric irregularities in mid- auroral and polar latitudes. Finally, since RAX payload is a 5-min snapshot radar receiver with postprocessing of radar signals, simultaneous multi-beam capabilities of PFISR and RISR can also be used with RAX.
This workshop invites presentations about recent findings on mid-to-high ionospheric irregularities in the form of short-scale plasma turbulence (including Polar Mesospheric Summer Echoes) and how RAX mission can test/confirm these findings or test our current theoretical understanding. In particular, we invite plasma turbulence research with RAX, including active ionospheric experiments. Furthermore, we welcome presentations on plans for potential opportunistic measurements between RAX and other ground- or space-based instruments if they are near by.
Student Description
The Radio Aurora Explorer (RAX) satellite mission, currently planned for launch in 2010, is a ground-to-space bistatic radar experiment to study aspects of mid- and high-latitude ionospheric plasma turbulence that cannot be studied from ground or space alone. The turbulence creates radar clutter, disrupts or degrades communication and navigation signals, and contributes an unknown amount to the energetics of the upper atmosphere. This workshop is about the current state of knowledge of the E and F region ionospheric irregularities and how RAX can improve our understanding of the micro-physics of the plasma instabilities in these regions.
By plasma turbulence, we refer to meter-scale ionospheric electron density irregularities that are 1-10% of the background density. Because of much stronger plasma diffusion rates parallel to the magnetic field lines (as opposed to perpendicular), the irregularities are magnetic field-aligned, so called "field-aligned irregularities" or FAI. Because of their field-aligned nature and because the magnetic field lines in the higher latitudes are close to vertical, it is difficult to detect and monitor them with a radar on the ground because the radar echoes escape to space. The RAX mission is designed to catch these echoes in space. Note that the smallness of the RAX UHF antenna is compensated by the utilization of MW-range UHF incoherent scatter radars (ISR) to illuminate the plasma irregularities. Furthermore, the echoes returning to the ISRs can be used to measure the electric field and the background plasma density and temperatures of the turbulent volume, allowing us to observe the conditions in which plasma instabilities occur.
From this experiment, we expect to map ionospheric irregularities from 80-400 km altitudes under different electric field conditions and altitude profiles of background electron density. More specifically, we expect to measure the magnetic elongation of the irregularities to understand the saturation mechanisms of plasma instabilities, such as the Farley-Buneman instability.
Workshop Summary
This is where the final summary workshop report will be.
Presentation Resources
Upload presentation and link to it here. Links to other resources.
- Add links to your presentations here, including agendas, that are uploaded above. Please add bullets to separate talks. See further information on how to upload a file and link to it.
