Search Results - "Galand, M."

Cold electrons at a weakly outgassing comet by Stephenson, P, Galand, M, Deca, J, Henri, P

“…ABSTRACT Throughout the Rosetta mission, cold electrons (<1 eV) were measured in the coma of comet 67P/Churyumov–Gerasimenko. Cometary electrons are produced…”
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PREDICTIONS OF ION PRODUCTION RATES AND ION NUMBER DENSITIES WITHIN THE DIAMAGNETIC CAVITY OF COMET 67P/CHURYUMOV-GERASIMENKO AT PERIHELION by Vigren, E, Galand, M

“…We present a one-dimensional ion chemistry model of the diamagnetic cavity of comet 67P/Churyumov-Gerasimenko, the target comet for the ESA Rosetta mission. We…”
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A collisional test-particle model of electrons at a comet by Stephenson, Peter, Galand, M, Deca, J, Henri, P, Carnielli, G

“…ABSTRACT We have developed the first 3D collisional model of electrons at a comet, which we use to examine the impact of electron-neutral collisions in the…”
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Constraining ion transport in the diamagnetic cavity of comet 67P by Lewis, Z M, Beth, A, Galand, M, Henri, P, Rubin, M, Stephenson, P

“…ABSTRACT The European Space Agency Rosetta mission escorted comet 67P for a 2-yr section of its six and a half-year orbit around the Sun. By perihelion in 2015…”
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Effects of the convective field on weakly outgassing comets by Beth, A, Galand, M

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Energy deposition and primary chemical products in Titan’s upper atmosphere by Lavvas, P., Galand, M., Yelle, R.V., Heays, A.N., Lewis, B.R., Lewis, G.R., Coates, A.J.

“…► We have performed detailed calculations for the energy deposition of photons and photoelectrons in Titan’s atmosphere. ► We use new, high-resolution cross…”
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Origin and trends in NH4+ observed in the coma of 67P by Lewis, Z M, Beth, A, Altwegg, K, Galand, M, Goetz, C, Heritier, K, O’Rourke, L, Rubin, M, Stephenson, P

“…ABSTRACT The European Space Agency/Rosetta mission escorted comet 67P/Churyumov–Gerasimenko and witnessed the evolution of its coma from low activity (∼2.5–3.8…”
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Time variability and heterogeneity in the coma of 67P/Churyumov-Gerasimenko by Hässig, M., Altwegg, K., Balsiger, H., Bar-Nun, A., Berthelier, J. J., Bieler, A., Bochsler, P., Briois, C., Calmonte, U., Combi, M., De Keyser, J., Eberhardt, P., Fiethe, B., Fuselier, S. A., Galand, M., Gasc, S., Gombosi, T. I., Hansen, K. C., Jäckel, A., Keller, H. U., Kopp, E., Korth, A., Kührt, E., Le Roy, L., Mall, U., Marty, B., Mousis, O., Neefs, E., Owen, T., Rème, H., Rubin, M., Sémon, T., Tornow, C., Tzou, C.-Y., Waite, J. H., Wurz, P.

“…Comets contain the best-preserved material from the beginning of our planetary system. Their nuclei and comae composition reveal clues about physical and…”
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The source of electrons at comet 67P by Stephenson, P, Beth, A, Deca, J, Galand, M, Goetz, C, Henri, P, Heritier, K, Lewis, Z, Moeslinger, A, Nilsson, H, Rubin, M

“…ABSTRACT We examine the origin of electrons in a weakly outgassing comet, using Rosetta mission data and a 3D collisional model of electrons at a comet. We…”
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Diamagnetic region(s): structure of the unmagnetized plasma around Comet 67P/CG by Henri, P., Vallières, X., Hajra, R., Goetz, C., Richter, I., Glassmeier, K.-H., Galand, M., Rubin, M., Eriksson, A. I., Nemeth, Z., Vigren, E., Beth, A., Burch, J.L., Carr, C., Nilsson, H., Tsurutani, B., Wattieaux, G.

“…Abstract The ESA’s comet chaser Rosetta has monitored the evolution of the ionized atmosphere of comet 67P/Churyumov–Gerasimenko (67P/CG) and its interaction…”
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Day‐to‐night transport in the Martian ionosphere: Implications from total electron content measurements by Cui, J., Galand, M., Yelle, R. V., Wei, Y., Zhang, S.‐J.

“…The nightside Martian ionosphere is thought to be contributed by day‐to‐night transport and electron precipitation, of which the former has not been well…”
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On the origin of molecular oxygen in cometary comae by Heritier, K. L., Altwegg, K., Berthelier, J.-J., Beth, A., Carr, C. M., De Keyser, J., Eriksson, A. I., Fuselier, S. A., Galand, M., Gombosi, T. I., Henri, P., Johansson, F. L., Nilsson, H., Rubin, M., Simon Wedlund, C., Taylor, M. G. G. T., Vigren, E

“…We have used generous assumptions in terms of production rates and ion fluxes to assess the production of O2- through ER reactions as a mechanism to explain…”
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Energy deposition in Saturn’s equatorial upper atmosphere by Chadney, J.M., Koskinen, T.T., Hu, X., Galand, M., Lavvas, P., Unruh, Y.C., Serigano, J., Hörst, S.M., Yelle, R.V.

“…We construct Saturn equatorial neutral temperature and density profiles of H, H2, He, and CH4, between 10−12 and 1 bar using measurements from Cassini’s Ion…”
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Modelling H3+ in planetary atmospheres: effects of vertical gradients on observed quantities by Moore, L., Melin, H., O'Donoghue, J., Stallard, T. S., Moses, J. I., Galand, M., Miller, S., Schmidt, C. A.

“…Since its detection in the aurorae of Jupiter approximately 30 years ago, the H 3 + ion has served as an invaluable probe of giant planet upper atmospheres…”
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Saturn ring rain: Model estimates of water influx into Saturn’s atmosphere by Moore, L., O’Donoghue, J., Müller-Wodarg, I., Galand, M., Mendillo, M.

“…•We compare modeled and observed H3+ column densities in Saturn’s ionosphere.•Variations in H3+ densities give insight into water influxes from Saturn’s…”
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The Evolution of the Electron Number Density in the Coma of Comet 67P at the Location of Rosetta from 2015 November through 2016 March by Vigren, E., Edberg, N. J. T., Eriksson, A. I., Galand, M., Henri, P., Johansson, F. L., Odelstad, E., Rubin, M., Valliéres, X.

“…A comet ionospheric model assuming the plasma moves radially outward with the same bulk speed as the neutral gas and not being subject to severe reduction…”
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Modelling H 3 + in planetary atmospheres: effects of vertical gradients on observed quantities by Moore, L, Melin, H, O'Donoghue, J, Stallard, T S, Moses, J I, Galand, M, Miller, S, Schmidt, C A

“…Since its detection in the aurorae of Jupiter approximately 30 years ago, the H ion has served as an invaluable probe of giant planet upper atmospheres…”
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Magnetosphere–atmosphere coupling at Saturn: 1 – Response of thermosphere and ionosphere to steady state polar forcing by Müller-Wodarg, I.C.F., Moore, L., Galand, M., Miller, S., Mendillo, M.

“…► We self-consistently calculate Saturn magnetosphere–ionosphere–thermosphere coupling. ► Magnetospheric energy controls flow of mass and energy in Saturn’s…”
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Vertical structure of the near-surface expanding ionosphere of comet 67P probed by Rosetta by Heritier, K. L., Henri, P., Vallières, X., Galand, M., Odelstad, E., Eriksson, A. I., Johansson, F. L., Altwegg, K., Behar, E., Beth, A., Broiles, T. W., Burch, J. L., Carr, C. M., Cupido, E., Nilsson, H., Rubin, M., Vigren, E.

“…Abstract The plasma environment has been measured for the first time near the surface of a comet. This unique data set has been acquired at…”
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Negative ion chemistry in Titan's upper atmosphere by Vuitton, V., Lavvas, P., Yelle, R.V., Galand, M., Wellbrock, A., Lewis, G.R., Coates, A.J., Wahlund, J.-E.

“…The Electron Spectrometer (ELS), one of the sensors making up the Cassini Plasma Spectrometer (CAPS) revealed the existence of numerous negative ions in…”
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