Title: Carbon dioxide photoelectron energy peaks at Mars

Author(s): Frahm RA, Winningham JD, Sharber JR, Scherrer JR, Jeffers SJ, Coates AJ, Linder DR, Kataria DO, Lundin R, Barabash S, Holmstrom M, Andersson H, Yamauchi M, Grigoriev A, Kallio E, Sales T, Riihela P, Schmidt W, Koskinen H, Kozyra JU, Luhmann JG, Roelof EC, Williams DJ, Livi S, Curtis CC, Hsieh KC, Sandel BR, Grande M, Carter M, Sauvaud JA, Fedorov A, Thocaven JJ, McKenna-Lawler S, Orsini S, Cerulli-Irelli R, Maggi M, Wurz P, Bochsler P, Krupp N, Woch J, Franz M, Asamura K, Dierker C

Source: ICARUS 182 (2): 371-382 JUN 2006

Document Type: Article

Language: English

Abstract: The ELectron Spectrometer (ELS) from the Analyzer of Space Plasmas and Energetic Atoms (ASPERA-3) flown on the Mars Express spacecraft has an No energy resolution. combined with the capability to oversample the martian electron distribution. This makes possible the resolution and identification of electrons generated as a result of the He 304 angstrom ionization of CO2 at the martian exobase on the dayside of the planet. Ionospheric photoelectrons were observed during, almost every pass into the ionosphere and CO2 photoelectron peaks were identified near the terminator. Atmospherically generated CO2 photoelectrons are also observed at 10,000 km altitude in the martian tail near the inner magnetospheric boundary. Observations over a wide range of spacecraft orbits showed a consistent presence of photoelectrons at locations along the inner magnetospheric boundary and in the ionosphere, front an altitude of 250 to 10,000 km. (c) 2006 Elsevier Inc. All rights reserved.

Author Keywords: Mars; ionospheres; atmospheres; magnetospheres

KeyWords Plus: MAGNETIC-FIELD; IONOSPHERE; ELECTRON

Addresses: Frahm RA (reprint author), SW Res Inst, PO Drawer 28510, San Antonio, TX 78228 USA
SW Res Inst, San Antonio, TX 78228 USA
Univ Coll London, Mullard Space Sci Lab, Dorking, Surrey RH5 6NT England
Swedish Inst Space Phys, Kiruna, S-98128 Sweden
Finnish Meteorol Inst, Helsinki, FIN-00101 Finland
Univ Helsinki, Dept Phys Sci, Helsinki, FIN-00014 Finland
Univ Michigan, Space Phys Res Lab, Ann Arbor, MI 48109 USA
Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA
Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA
Univ Arizona, Tucson, AZ 85721 USA
Rutherford Appleton Lab, Didcot, Oxon OX11 0QX England
Ctr Etud Spatiale Rayonnements, Toulouse, F-31028 France
Natl Univ Ireland, Space Technol Ireland, Maynooth, Kildare Ireland
Ist Fis Spazio Interplanetari, Rome, I-00133 Italy
Univ Bern, Inst Phys, Bern, CH-3012 Switzerland
Max Planck Inst Aeron, Katlenburg Lindau, D-37191 Germany
Inst Space & Astronaut Sci, Sagamihara, Japan
Tech Univ Carolo Wilhelmina Braunschweig, Braunschweig, D-38106 Germany

E-mail Addresses: rfrahm@swri.edu

Publisher: ACADEMIC PRESS INC ELSEVIER SCIENCE, 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA

Subject Category: ASTRONOMY & ASTROPHYSICS

IDS Number: 052JE