Abstract:
We present electron temperature and density measurements of Titan's cold ionospheric plasma from the Langmuir probe instrument on Cassini from 52 flybys. An expression of the density as a function of temperature is presented for altitudes below two Titan radii. The density falls off exponentially with increased temperature as log(ne) = -2.0log(Te) + 0.6 on average around Titan. We show that this relation varies with location around Titan as well as with the solar illumination direction. Significant heating of the electrons appears to take place on the night/wake side of Titan as the density-temperature relation is less steep there. Furthermore, we show that the magnetospheric ram pressure is not balanced by the thermal and magnetic pressure in the topside ionosphere and discuss its implications for plasma escape. The cold ionospheric plasma of Titan extends to higher altitudes in the wake region, indicating the loss of atmosphere down the induced magnetospheric tail. © 2010 by the American Geophysical Union.
Registro:
Documento: |
Artículo
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Título: | Electron density and temperature measurements in the cold plasma environment of Titan: Implications for atmospheric escape |
Autor: | Edberg, N.J.T.; Wahlund, J.-E.; Ågren, K.; Morooka, M.W.; Modolo, R.; Bertucci, C.; Dougherty, M.K. |
Filiación: | Swedish Institute of Space Physics, Box 537, SE-75121 Uppsala, Sweden LATMOS, IPSL, UVSQ, 11 blvd. d'Alembert, F-78280 Guyancourt CEDEX, France Institute for Astronomy and Space Physics, Ciudad Universitaria, Casilla de Correo 67-Suc. 28, C1428ZAA Buenos Aires, Argentina Space and Atmospheric Physics Group, Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BW, United Kingdom
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Palabras clave: | Electron temperature; Heating; Ionosphere; Magnetosphere; Temperature measurement; Thermal logging; Atmospheric escape; Cassini; Cold plasmas; Density Measurements; Electron density and temperature measurements; Increased temperature; Ionospheric plasmas; Langmuirs; Magnetic pressure; Magnetospheric tail; Probe instruments; Solar illumination; Top-side ionosphere; Wake region; Atmospheric temperature; air temperature; atmospheric electricity; electron density; heating; ionosphere; magnetosphere; plasma; solar activity |
Año: | 2010
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Volumen: | 37
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Número: | 20
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DOI: |
http://dx.doi.org/10.1029/2010GL044544 |
Título revista: | Geophysical Research Letters
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Título revista abreviado: | Geophys. Res. Lett.
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ISSN: | 00948276
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CODEN: | GPRLA
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Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00948276_v37_n20_p_Edberg |
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Citas:
---------- APA ----------
Edberg, N.J.T., Wahlund, J.-E., Ågren, K., Morooka, M.W., Modolo, R., Bertucci, C. & Dougherty, M.K.
(2010)
. Electron density and temperature measurements in the cold plasma environment of Titan: Implications for atmospheric escape. Geophysical Research Letters, 37(20).
http://dx.doi.org/10.1029/2010GL044544---------- CHICAGO ----------
Edberg, N.J.T., Wahlund, J.-E., Ågren, K., Morooka, M.W., Modolo, R., Bertucci, C., et al.
"Electron density and temperature measurements in the cold plasma environment of Titan: Implications for atmospheric escape"
. Geophysical Research Letters 37, no. 20
(2010).
http://dx.doi.org/10.1029/2010GL044544---------- MLA ----------
Edberg, N.J.T., Wahlund, J.-E., Ågren, K., Morooka, M.W., Modolo, R., Bertucci, C., et al.
"Electron density and temperature measurements in the cold plasma environment of Titan: Implications for atmospheric escape"
. Geophysical Research Letters, vol. 37, no. 20, 2010.
http://dx.doi.org/10.1029/2010GL044544---------- VANCOUVER ----------
Edberg, N.J.T., Wahlund, J.-E., Ågren, K., Morooka, M.W., Modolo, R., Bertucci, C., et al. Electron density and temperature measurements in the cold plasma environment of Titan: Implications for atmospheric escape. Geophys. Res. Lett. 2010;37(20).
http://dx.doi.org/10.1029/2010GL044544