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ISSN  2096-3955

CN  10-1502/P

Citation: Wu, X. S., Cui, J., Yu, J., Liu, L. J., and Zhou, Z. J. (2019). Photoelectron balance in the dayside Martian upper atmosphere. Earth Planet. Phys., 3(5), 373–379.doi: 10.26464/epp2019038

2019, 3(5): 373-379. doi: 10.26464/epp2019038


Photoelectron balance in the dayside Martian upper atmosphere


National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100101, China


School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai Guangdong 519082, China


Chinese Academy of Sciences Center for Excellence in Comparative Planetology, Hefei 230026, China


Space Science Institute, Macau University of Science and Technology, Macau, China

Corresponding author: Jun Cui,

Received Date: 2019-06-04
Web Publishing Date: 2019-09-01

Photoelectrons are produced by solar Extreme Ultraviolet radiation and contribute significantly to the local ionization and heat balances in planetary upper atmospheres. When the effect of transport is negligible, the photoelectron energy distribution is controlled by a balance between local production and loss, a condition usually referred to as local energy degradation. In this study, we examine such a condition for photoelectrons near Mars, with the aid of a multi-instrument Mars Atmosphere and Volatile Evolution data set gathered over the inbound portions of a representative dayside MAVEN orbit. Various photoelectron production and loss processes considered here include primary and secondary ionization, inelastic collisions with atmospheric neutrals associated with both excitation and ionization, as well as Coulomb collisions with ionospheric thermal electrons. Our calculations indicate that photoelectron production occurs mainly via primary ionization and degradation from higher energy states during inelastic collisions; photoelectron loss appears to occur almost exclusively via degradation towards lower energy states via inelastic collisions above 10 eV, but the effect of Coulomb collisions becomes important at lower energies. Over the energy range of 30–55 eV (chosen to reduce the influence of the uncertainty in spacecraft charging), we find that the condition of local energy degradation is very well satisfied for dayside photoelectrons from 160 to 250 km. No evidence of photoelectron transport is present over this energy range.

Key words: Mars, Photoelectron, MAVEN

Benna, M., Mahaffy, P. R., Grebowsky, J. M., Fox, J. L., Yelle, R. V., and Jakosky, B. M. (2015). First measurements of composition and dynamics of the Martian ionosphere by MAVEN’s Neutral Gas and Ion Mass Spectrometer. Geophys. Res. Lett., 42(21), 8958–8965.

Bhardwaj, A., and Jain, S. K. (2009). Monte Carlo model of electron energy degradation in a CO2 atmosphere. J. Geophys. Res. Space Phys., 114(A11), A11309.

Brain, D. A., Mitchell, D. L., and Halekas, J. S. (2006). The magnetic field draping direction at Mars from April 1999 through August 2004. Icarus, 182(2), 464–473.

Chen, R. H., Cravens, T. E., and Nagy, A. F. (1978). The Martian ionosphere in light of the Viking observations. J. Geophys. Res. Space Phys., 83(A8), 3871–3876.

Choi, Y. W., Kim, J., Min, K. W., Nagy, A. F., and Oyama, K. I. (1998). Effect of the magnetic field on the energetics of Mars ionosphere. Geophys. Res. Lett., 25(14), 2753–2756.

Coates, A. J., Frahm, R. A., Linder, D. R., Kataria, D. O., Soobiah, Y., Collinson, G., Sharber, J. R., Winningham, J. D., Jeffers, S. J., … Grande, M. (2008). Ionospheric photoelectrons at Venus: Initial observations by ASPERA-4 ELS. Planet. Space Sci., 56(6), 802–806.

Coates, A. J., Crary, F. J., Young, D. T., Szego, K., Arridge, C. S., Bebesi, Z., Sittler, Jr. E. C., Hartle, R. E., and Hill, T. W. (2007). Ionospheric electrons in Titan’s tail: Plasma structure during the Cassini T9 encounter. Geophys. Res. Lett., 34(24), L24S05.

Coates, A. J., Tsang, S. M. E., Wellbrock, A., Frahm, R. A., Winningham, J. D., Barabash, S., Lundin, R., Young, D. T., and Crary, F. J. (2011). Ionospheric photoelectrons: Comparing Venus, Earth, Mars and Titan. Planet. Space Sci., 59(10), 1019–1027.

Coates, A. J., Wellbrock, A., Frahm, R. A., Winningham, J. D., Fedorov, A., Barabash, S., and Lundin, R. (2015). Distant ionospheric photoelectron energy peak observations at Venus. Planet. Space Sci., 113-114, 378–384.

Cui, J., Yelle, R. V., Vuitton, V., Waite, Jr. J. H., Kasprzak, W. T., Gell, D. A., Niemann, H. B., Müller-Wodarg, I. C. F., Borggren, N., … Magee, B. A. (2009). Analysis of Titan’s neutral upper atmosphere from Cassini Ion Neutral Mass Spectrometer measurements. Icarus, 200(2), 581–615.

Cui, J., Galand, M., Coates, A. J., Zhang, T. L., and Müller-Wodarg, I. C. F. (2011). Suprathermal electron spectra in the Venus ionosphere. J. Geophys. Res. Space Phys., 116(A4), A04321.

Cui, J., Wu, X. S., Xu, S. S., Wang, X. D., Wellbrock, A., Nordheim, T. A., Cao, Y. T., Wang, W. R., Sun, W. Q., … Wei, Y. (2018). Ionization efficiency in the dayside Martian upper atmosphere. Astrophys. J. Lett., 857(2), L18.

Cui, J., Cao, Y. T., Wu, X. S., Xu, S. S., Yelle, R. V., Stone, S., Vigren, E., Edberg, N. J. T., Shen, C. L., He, F., and Wei, Y. (2019). Evaluating local ionization balance in the nightside Martian upper atmosphere during MAVEN Deep Dip campaigns. Astrophys. J. Lett., 876(1), L12.

Doering, J. P., Peterson, W. K., Bostrom, C. O., and Potemra, T. A. (1976). High resolution daytime photoelectron energy spectra from AE-E. Geophys. Res. Lett., 3(3), 129–131.

Ergun, R. E., Morooka, M. W., Andersson, L. A., Fowler, C. M., Delory, G. T., Andrews, D. J., Eriksson, A. I., McEnulty, T., and Jakosky, B. M. (2015). Dayside electron temperature and density profiles at Mars: First results from the MAVEN Langmuir probe and waves instrument. Geophys. Res. Lett., 42(21), 8846–8853.

Fox, J. L., Galand, M. I., and Johnson, R. E. (2008). Energy deposition in planetary atmospheres by charged particles and solar photons. Space Sci. Rev., 139(1-4), 3–62.

Frahm, R. A., Winningham, J. D., Sharber, J. R., Scherrer, J. R., Jeffers, S. J., Coates, A. J., Linder, D. R., Kataria, D. O., Lundin, R., … Dierker, C. (2006a). Carbon dioxide photoelectron energy peaks at Mars. Icarus, 182(2), 371–382.

Frahm, R. A., Sharber, J. R., Winningham, J. D., Wurz, P., Liemohn, M. W., Kallio, E., Yamauchi, M., Lundin, R., Barabash, S., … McKenna-Lawer, S. (2006b). Locations of atmospheric photoelectron energy peaks within the Mars environment. Space Sci. Rev., 126(1-4), 389–402.

Frahm, R. A., Sharber, J. R., Winningham, J. D., Link, R., Liemohn, M. W., Kozyra, J. U., Coates, A. J., Linder, D. R., Barabash, S., … Fedorov, A. (2010). Estimation of the escape of photoelectrons from Mars in 2004 liberated by the ionization of carbon dioxide and atomic oxygen. Icarus, 206(1), 50–63.

Han, X., Fraenz, M., Dubinin, E., Wei, Y., Andrews, D. J., Wan, W., He, M., Rong, Z. J., Chai, L., … Barabash, S. (2014). Discrepancy between ionopause and photoelectron boundary determined from Mars Express measurements. Geophys. Res. Lett., 41(23), 8221–8227.

Heays, A. N., Bosman, A. D., and van Dishoeck, E. F. (2017). Photodissociation and photoionisation of atoms and molecules of astrophysical interest. Astron. Astrophys., 602, A105.

Itikawa, Y. (2002). Cross sections for electron collisions with carbon dioxide. J. Phys. Chem. Ref. Data, 31(3), 749–769.

Jakosky, B. M., Grebowsky, J. M., Luhmann, J. G., and Brain, D. A. (2015). Initial results from the MAVEN mission to Mars. Geophys. Res. Lett., 42(21), 8791–8802.

Kitamura, N., Seki, K., Nishimura, Y., and McFadden, J. P. (2015). Limited impact of escaping photoelectrons on the terrestrial polar wind flux in the polar cap. Geophys. Res. Lett., 42(9), 3106–3113.

Lavvas, P., Galand, M., Yelle, R. V., Heays, A. N., Lewis, B. R., Lewis, G. R., and Coates, A. J. (2011). Energy deposition and primary chemical products in Titan’s upper atmosphere. Icarus, 213(1), 233–251.

Lee, J. S., Doering, J. P., Potemra, T. A., and Brace, L. H. (1980). Measurements of the ambient photoelectron spectrum from atmosphere explorer: Ⅰ. AE-E measurements below 300 km during solar minimum conditions. Planet. Space Sci., 28(10), 947–971.

Lee, J. S., Doering, J. P., Potemra, T. A., and Brace, L. H. (1980). Measurements of the ambient photoelectron spectrum from atmosphere explorer: Ⅱ. AE-E measurements from 300 to 1000 km during solar minimum conditions. Planet. Space Sci., 28(10), 973–996.

Liemohn, M. W., Dupre, A., Bougher, S. W., Trantham, M., Mitchell, D. L., and Smith, M. D. (2012). Time-history influence of global dust storms on the upper atmosphere at Mars. Geophys. Res. Lett., 39(11), L11201.

Mahaffy, P. R., Benna, M., Elrod, M., Yelle, R. V., Bougher, S. W., Stone, S. W., and Jakosky, B. M. (2015). Structure and composition of the neutral upper atmosphere of Mars from the MAVEN NGIMS investigation. Geophys. Res. Lett., 42(21), 8951–8957.

Mantas, G. P., and Hanson, W. B. (1979). Photoelectron fluxes in the Martian ionosphere. J. Geophys. Res., 84(A2), 369–385.

Matta, M., Galand, M., Moore, L., Mendillo, M., and Withers, P. (2014). Numerical simulations of ion and electron temperatures in the ionosphere of Mars: Multiple ions and diurnal variations. Icarus, 227, 78–88.

McFadden, J. P., Kortmann, O., Curtis, D., Dalton, G., Johnson, G., Abiad, R., Sterling, R., Hatch, K., Berg, P., … Jakosky, B. (2015). MAVEN suprathermal and thermal ion compostion (STATIC) instrument. Space Sci. Rev., 195(1-4), 199–256.

Mitchell, D. L., Lin, R. P., Rème, H., Crider, D. H., Cloutier, P. A., Connerney, J. E. P., Acuña, M. H., and Ness, N. F. (2000). Oxygen auger electrons observed in Mars’ ionosphere. Geophys. Res. Lett., 27(13), 1871–1874.

Mitchell, D. L., Mazelle, C., Sauvaud, J. A., Thocaven, J. J., Rouzaud, J., Fedorov, A., Rouger, P., Toublanc, D., Taylor, E., … Jakosky, B. M. (2016). The MAVEN solar wind electron analyzer. Space Sci. Rev., 200(1-4), 495–528.

Nicholson, W. P., Gronoff, G., Lilensten, J., Aylward, A. D., and Simon, C. (2009). A fast computation of the secondary ion production in the ionosphere of Mars. Mon. Not. R. Astron. Soc., 400(1), 369–382.

Peterson, W. K., Thiemann, E. M. B., Eparvier, F. G., Andersson, L., Fowler, C. M., Larson, D., Mitchell, D., Mazelle, C., Fontenla, J., … Jakosky, B. (2016). Photoelectrons and solar ionizing radiation at Mars: Predictions versus MAVEN observations. J. Geophys. Res. Space Phys., 121(9), 8859–8870.

Peterson, W. K., Fowler, C. M., Andersson, L. A., Thiemann, E. M. B., Jain, S. K., Mayyasi, M., Esman, T. M., Yelle, R., Benna, M., and Espley, J. (2018). Martian electron temperatures in the subsolar region: MAVEN observations compared to a one-dimensional model. J. Geophys. Res. Space Phys., 123(7), 5960–5973.

Sakai, S., Rahmati, A., Mitchell, D. L., Cravens, T. E., Bougher, S. W., Mazelle, C., Peterson, W. K., Eparvier, F. G., Fontenla, J. M., and Jakosky, B. M. (2015). Model insights into energetic photoelectrons measured at Mars by MAVEN. Geophys. Res. Lett., 42(21), 8894–8900.

Shutte, N. M., Király, P., Cravens, T. E., Dyachkov, A. V., Gombos, T. I., Gringuaz, K. I., Nagy, A. F., Sharp, W. E., Sheronova, S. M., … Verigin, M. (1989). Observation of electron and ion fluxes in the vicinity of Mars with the HARP spectrometer. Nature, 341(6243), 614–616.

Stamnes, K., and Rees, M. H. (1983). Heating of thermal ionospheric electrons by suprathermal electrons. Geophys. Res. Lett., 10(4), 309–312.

Stone, S. W., Yelle, R. V., Benna, M., Elrod, M. K., and Mahaffy, P. R. (2018). Thermal structure of the Martian upper atmosphere from MAVEN NGIMS. J. Geophys. Res. Planets, 123(11), 2842–2867.

Thiemann, E. M. B., Chamberlin, P. C., Eparvier, F. G., Templeman, B., Woods, T. N., Bougher, S. W., and Jakosky, B. M. (2017). The MAVEN EUVM model of solar spectral irradiance variability at Mars: Algorithms and results. J. Geophys. Res. Space Phys., 122(3), 2748–2767.

Trantham, M., Liemohn, M., Mitchell, D., and Frank, J. (2011). Photoelectrons on closed crustal field lines at Mars. J. Geophys. Res. Space Phys., 116(A7), A07311.

Tsang, S. M. E., Coates, A. J., Jones, G. H., Frahm, R. A., Winningham, J. D., Barabash, S., Lundin, R., and Fedorov, A. (2015). Ionospheric photoelectrons at Venus: Case studies and first observation in the tail. Planet. Space Sci., 113-114, 385–394.

Wellbrock, A., Coates, A. J., Sillanpää, I., Jones, G. H., Arridge, C. S., Lewis, G. R., Young, D. T., Crary, F. J., and Aylward, A. D. (2012). Cassini observations of ionospheric photoelectrons at large distances from Titan: Implications for Titan’s exospheric environment and magnetic tail. J. Geophys. Res. Space Phys., 117(A3), A03216.

Xu, S. S., Liemohn, M., Bougher, S., and Mitchell, D. (2016a). Martian high-altitude photoelectrons independent of solar zenith angle. J. Geophys. Res. Space Phys., 121(4), 3767–3780.

Xu, S. S., Mitchell, D., Liemohn, M., Dong, C. F., Bougher, S., Fillingim, F., Lillis, R., McFadden, J., Mazelle, C., … Jakosky, B. (2016b). Deep nightside photoelectron observations by MAVEN SWEA: Implications for Martian northern hemispheric magnetic topology and nightside ionosphere source. Geophys. Res. Lett., 43(17), 8876–8884.

Xu, S. S., Mitchell, D., Liemohn, M., Fang, X. H., Ma, Y. J., Luhmann, J., Brain, D., Steckiewicz, M., Mazelle, C., … Jakosky, B. (2017a). Martian low-altitude magnetic topology deduced from MAVEN/SWEA observations. J. Geophys. Res. Space Phys., 122(2), 1831–1852.

Xu, S. S., Mitchell, D., Luhmann, J., Ma, Y. J., Fang, X. H., Harada, Y., Hara, T., Brain, D., Weber, T., … DiBraccio, G. A. (2017b). High-altitude closed magnetic loops at Mars observed by MAVEN. Geophys. Res. Lett., 44(22), 11229–11238.


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Photoelectron balance in the dayside Martian upper atmosphere

XiaoShu Wu, Jun Cui, Jiang Yu, LiJuan Liu, ZhenJun Zhou