Imperial College London

DrMarinaGaland

Faculty of Natural SciencesDepartment of Physics

Reader in Planetary Science
 
 
 
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Contact

 

m.galand Website

 
 
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Location

 

Huxley BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Vigren:2016:3/59,
author = {Vigren, E and Altwegg, K and Edberg, NJT and Eriksson, AI and Galand, M and Henri, P and Johansson, F and Odelstad, E and Tzou, C-Y and ValliƩres, X},
doi = {3/59},
journal = {Astronomical Journal},
title = {MODEL-OBSERVATION COMPARISONS OF ELECTRON NUMBER DENSITIES IN THE COMA OF 67P/CHURYUMOV–GERASIMENKO DURING 2015 JANUARY},
url = {http://dx.doi.org/10.3847/0004-6256/152/3/59},
volume = {152},
year = {2016}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - During 2015 January 9–11, at a heliocentric distance of ~2.58–2.57 au, the ESA Rosetta spacecraft resided at a cometocentric distance of ~28 km from the nucleus of comet 67P/Churyumov–Gerasimenko, sweeping the terminator at northern latitudes of 43°N–58°N. Measurements by the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis/Comet Pressure Sensor (ROSINA/COPS) provided neutral number densities. We have computed modeled electron number densities using the neutral number densities as input into a Field Free Chemistry Free model, assuming H2O dominance and ion-electron pair formation by photoionization only. A good agreement (typically within 25%) is found between the modeled electron number densities and those observed from measurements by the Mutual Impedance Probe (RPC/MIP) and the Langmuir Probe (RPC/LAP), both being subsystems of the Rosetta Plasma Consortium. This indicates that ions along the nucleus-spacecraft line were strongly coupled to the neutrals, moving radially outward with about the same speed. Such a statement, we propose, can be further tested by observations of H3O+/H2O+ number density ratios and associated comparisons with model results.
AU - Vigren,E
AU - Altwegg,K
AU - Edberg,NJT
AU - Eriksson,AI
AU - Galand,M
AU - Henri,P
AU - Johansson,F
AU - Odelstad,E
AU - Tzou,C-Y
AU - ValliƩres,X
DO - 3/59
PY - 2016///
SN - 1538-3881
TI - MODEL-OBSERVATION COMPARISONS OF ELECTRON NUMBER DENSITIES IN THE COMA OF 67P/CHURYUMOV–GERASIMENKO DURING 2015 JANUARY
T2 - Astronomical Journal
UR - http://dx.doi.org/10.3847/0004-6256/152/3/59
UR - http://hdl.handle.net/10044/1/41111
VL - 152
ER -