Abstract
The Radio Plasma Imager (RPI) on the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) spacecraft was designed as a long-range magnetospheric radio sounder, relaxation sounder, and a passive plasma wave instrument. The RPI is a highly flexible instrument that can be programmed to perform these types of measurements at times when IMAGE is located in key regions of the magnetosphere. RPI is the first radio sounder ever flown to large radial distances into the magnetosphere.
The long-range sounder echoes from RPI allow remote sensing of a variety of plasmas structures and boundaries in the magnetosphere. A profile inversion technique for RPI echo traces has been developed and provides a method for determining the density distribution of the plasma from either direct or field-aligned echoes. This technique has enabled the determination of the evolving density structure of the polar cap and the plasmasphere under a variety of geomagnetic conditions. New results from RPI show that the plasmasphere refills in slightly greater than a day at L values of 2.8 and that ion heating is probably playing a major role in the overall density distribution along the field-line. In addition, RPF’s plasma resonance observations at large radial distances over the polar cap provided in situ measurements of the plasma density with an accuracy of a few percent. For the first time in the magnetosphere, RPI has also observed the plasma D resonances.
RPF’s long antennas and its very low noise receivers provide excellent observations in the passive receive-only mode when the instrument measures the thermal plasma noise as well as natural emissions such as the continuum radiation and auroral kilometric radiation (AKR). Recent passive measurements from RPI have been compared extensively with images from the Extreme Ultraviolet (EUV) imager on IMAGE resulting in a number of new discoveries. For instance, these combined observations show that kilometric continuum can be generated at the plasmapause from sources in or very near the magnetic equator, within a bite-out region of the plasmasphere. The process by which plasmaspheric bite-out structures are produced is not completely understood at this time.
Finally, RPI has been used to successfully test the feasibility of magnetospheric tomography. During perigee passages of the Wind spacecraft, RPI radio transmissions at one and two frequencies have been observed by the Waves instrument. The received electric field vector was observed to rotate with time due to the changing density of plasma, and thus Faraday rotation was measured. Many future multi-spacecraft missions propose to use Faraday rotation to obtain global density pictures of the magnetosphere.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Benson, R.F.: 1997, ‘Evidence for the stimulation of field-aligned electron density irregularities on a short time scale by ionospheric topside sounders’, J. Atm. and Solar-Terr. Phys. 59, 2281–2293.
Benson, R.F., Osherovich, V.A., Fainberg, J., and Reinisch, B.W.: 2003, ‘Classification of IMAGE/RPI-stimulated resonances for the accurate determination of magnetospheric electron-density and magnetic field values’ 108(A5), 1207, doi: 1029/2002JA009589, J. Geophys. Res.
Calvert, W., Benson, R.F., Carpenter, D.L., Fung, S.F., Gallagher, D.L., Green, J.L., Haines, D.M., Reiff, P.H., Reinisch, B.W., Smith, M.F. and Taylor, W.W.L.: 1995, The feasibility of radio sounding in the magnetosphere‘, Radio Science 30, 5, 1577–1615.
Calvert, W., Benson, R.F., Carpenter, D.L., Fung, S.F., Gallagher, D., Green, J.L., Haines, D.M., Reiff, P.H., Reinisch, B.W., Smith, M. and Taylor, W.W.L.: 1997, ‘Reply to R.A. Greenwald concerning the feasibility of radio sounding of the magnetosphere’, Radio Sci. 32, 1, 281–284.
Carpenter, D.L., Anderson, R.R., Calvert, W. and Moldwin, M.B.: 2000, ‘CRRES observations of density cavities inside the plasmasphere’, J. Geophys. Res. 105, 23323.
Carpenter, D.L., Spasojevic, M., Bell, T.F., Inan, U.S., Reinisch, B.W., Galkin, I.A., Benson, R.F., Green, J.L., Fung, S.F., Boardsen, S.A.: 2002, ‘Small-scale field-aligned plasmaspheric density structures inferred from RPI on IMAGE’, 107(A9), 1258, 10.1029/2001JA009199, J. Geophys. Res.
Chappell, C.R., Harris, K.K. and Sharp, G.W.: 1970, ‘A study of the influence of magnetic activity on the location of the plasmapause as measured by OGO-5’, J. Geophys. Res. 75, 50–56.
Cummer, S.A., Reiner, M.J., Reinisch, B.W., Kaiser, M.L., Green, J.L., Benson, R.F., Manning, R., Goetz, K.: 2001, ‘A test of magnetospheric radio tomographic imaging with IMAGE and WIND’, Geophys. Res. Letts. 28, 1131–1134.
Cummer, S.A., Green, J.L., Reinisch, B.W., Fung, S.F., Kaiser, M.L., Mutel, R., Pickett, J., Chistopher, I., Gurnett, D.A.: 2003, ‘Advances in Magnetospheric Radio Wave Analysis and Tomography’, Adv. Space Res. Accepted.
Ergun, R.E. et al.: 2000, ‘Feasibility of a multi-satellite investigation of the Earth’s magnetosphere with radio tomography’, J. Geophys. Res. 105, 361–373.
Fung, S.F., Benson, R.F., Green, J.L., Reinisch, B.W., Haines, D.M., Galkin, I.A., Bougeret, J.-L., Manning, R., Reiff, P.H., Gallagher, D.L., Carpenter, D.L. and Taylor, W.W.L.: 2002, ‘Observations of Magnetospheric Plasmas by the Radio Plasma Imager (RPI) on the IMAGE Mission’, Adv. Space Res. 30 (10), 2259–2266.
Fung, S.F., Benson, R.F., Carpenter, D.L., Green, J.L., Jayanti, V., Galkan, I.A. and Reinisch, B.W.: 2003, ‘Guided Echoes in the Magnetosphere: Observations by Radio Plasma Imager on IMAGE’ 30(11), 1589, doi: 10.1029/2002GL016531, Geophys. Res. Letts.
Gallagher, D.L., Craven, P.D. and Comfort, R.H.: 2000, ‘Global core plasma model’, J. Geophys. Res. 105, 18819.
Garcia, L.N., Fung, S.F., Green, J.L., Boardsen, S., Sandel, B.R. and Reinisch, B.W.: 2002, ‘Comparison of IMAGE RPI and EUV observations of plasma density structures outside of the plasmasphere’, Accepted J. Geophys. Res.
Goldstein, J., Spasojevic, M., Reiff, P.H., Sandel, B.R., Forrester, T., Gallagher, D.L. and Reinisch,B.W.: 2002, ‘Identifying the plasmapause in IMAGE EUV data using IMAGE RPI in situ steep gradients’, Accepted in J. Geophys. Res.
Grebowsky, J.M.: 1970, ‘Model study of plasmapause motion’, J. Geophys. Res. 75, 4329–4333.
Green, J.L., Gurnett, D.A. and Shawhan, S.D.: 1977, ‘The angular distribution of auroral kilometric radiation’, J. Geophys. Res. 82, 1825.
Green, J.L., Sandel, B.R., Fung, S.F., Gallagher, D.L. and Reinisch, B.W.: 2002, ‘On the Origin of Kilometric Continuum’, J. Geophys. Res. 107(A7), 10.1029/2001JA000193.
Green, J.L., Boardsen, S.A., Fung, S.F., Matsumoto, H., Hashimoto, K., Anderson, R.R., Sandel, B.R.and Reinisch, B.W.: 2003, ‘Association of Kilometric Continuum Radiation with Plasmaspheric Structures’, Submitted to J. Geophys. Res..
Greenwald, R.A.: January-February 1997a, ‘Comment on The feasibility of radio sounding of the magnetopause by W. Calvert et al.’, Radio Science 32, 277–280.
Greenwald, R.A.: May-June 1997b, ‘Rebuttal to reply by W. Calvert et al.’, Radio Science 32, 877–879.
Gurnett, D.A.: 1975, ‘The Earth as a radio source: The nonthermal continuum’, J. Geophys. Res. 80,2751–2763.
Hashimoto, K., Calvert, W. and Matsumoto, H.: 1999, ‘Kilometric continuum detected by Geotail’,J. Geophys. Res. 104, 28645–28656.
Huang, X. and Reinisch, B.W.: 1982, ‘Automatic calculation of electron density profiles from digital ionograms 2’. True height inversion of topside ionograms with the profile-fitting method, Radio Sci. 17, 837–844.
Larson, N.R., and Parks, G.K.: 1992, ‘Motions of particle microstructures in the magnetopause boundary layer’, J. Geophys. Res. 97, 10733–10749.
Nelms, G.L., and Lockwood, G.E.K.: 1967, ‘Early results from the topside sounder in the Alouette II satellite, Space Research VII’, in R.L. Smith-Rose (ed.), North-Holland Publishing Co.,Amsterdam, pp. 604–623.
Nsumei, P.A., Huang, X., Reinisch, B.W., Song, P., Vasyliunas, V.M., Green, J.L., Fung, S.F., Benson,R.F. and Gallagher, D.L.: 2003, ‘Electron Density distribution over the northern polar region deduced from IMAGE/RPI sounding’ 108(A2), 1078, doi: 1029/2002JA009616, J. Geophys. Res.
Park, C.G.: 1974, ‘Some features of plasma distribution in the plasmasphere deduced from Antarctic whistlers’, J. Geophys. Res. 79, 169–173.
Persoon, A.M., Gurnett, D.A. and Shawhan, S.D.: 1983, ‘Polar cap electron densities from DE 1 plasma wave observations’, J. Geophys. Res. 88, 10123.
Reinisch, B.W., Haines, D.M., Bibl, K., Cheney, G., Galkin, I.A., Huang, X., Myers, S.H. and Sales,G.S., Benson, R.F., Fung, S.F., Green, J.L., Taylor, W.W.L., Bougeret, J.-L., Manning, R., Meyer-Vernet,N., Moncuquet, M., Carpenter, D.L., Gallagher, D.L. and Reiff, P.: February, 2000, ‘The Radio Plasma Imager investigation on the IMAGE spacecraft’, Space Science Reviews, IMAGE special issue, 91, 319–359.
Reinisch, B.W., Huang, X., Haines, D.M., Galkin, I.A., Green, J.L., Benson, R.F., Fung, S.F., Taylor,W.W.L., Reiff, P.H., Gallagher, D.L., Bougeret, J.-L., Manning, R. and Carpenter, D.L.: 2001a,‘First Results from the Radio Plasma Imager on IMAGE’, Geophys. Res. Letts. 28, 1167–1170.
Reinisch, B.W., Huang, X., Song, P., Sales, G.S., Fung, S.F., Green, J.L., Gallagher, D.L. and Vasyliunas, V.M.: 2001b, ‘Plasma density distribution along the magnetospheric field: RPI observations from IMAGE’, Geophys. Res. Letts. 28, 4521–4524.
Reinisch, B.W., Huang, X., Song, P., Sales, G.S., Galkin, S.I., Benson, R., Fung, S.F. and Green,J.L.: 2002, ‘Radio Plasma Imager observation of magnetostorm effects on the plasmaspheric density distribution, abstract, 27th General Assembly of the International Union of Radio Science (URSI)’, Maastricht, The Netherlands, August 17–24, 2002.
Sandel, B.R., King, R.A., King, W.A., Forrester, W.T., Gallagher, D.L., Broadfoot, A.L. and Curtis, C.C.: 2001, ‘Initial results from the IMAGE Extreme Ultraviolet Imager’, Geophys. Res. Letts. 28, 1439–1442.
Sandel, B.R., Goldstein, J., Gallagher, D.L. and Carpenter, D.L.: 2003, ‘EUV Observations of the Structure and Dynamics of the Plasmasphere’, this issue.
Stix, T.H.: 1962, ‘The Theory of Plasma Waves’, McGraw-Hill, New York.
Tu, J., Horwitz, J.L., Song, P., Huang, X-Q, Reinisch, B.W. and P.G. Richards, P.G.: 2003, ‘Simulating plasmaspheric field-aligned density profiles measured with IMAGE/RPI: Effects of plasmasphere refilling and ion heating’, J. Geophys. Res. in press.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2003 Kluwer Academic Publishers
About this chapter
Cite this chapter
Green, J.L., Reinisch, B.W. (2003). An Overview of Results from RPI on IMAGE. In: Burch, J.L. (eds) Magnetospheric Imaging — The Image Prime Mission. Springer, Dordrecht. https://doi.org/10.1007/978-94-010-0027-7_9
Download citation
DOI: https://doi.org/10.1007/978-94-010-0027-7_9
Publisher Name: Springer, Dordrecht
Print ISBN: 978-1-4020-1646-2
Online ISBN: 978-94-010-0027-7
eBook Packages: Springer Book Archive