BibTex format
@article{Fuselier:2015:0004-6361/201526210,
author = {Fuselier, SA and Altwegg, K and Balsiger, H and Berthelier, JJ and Bieler, A and Briois, C and Broiles, TW and Burch, JL and Calmonte, U and Cessateur, G and Combi, M and De, Keyser J and Fiethe, B and Galand, M and Gasc, S and Gombosi, TI and Gune, H and Hansen, KC and Haessig, M and Jaeckel, A and Korth, A and Le, Roy L and Mall, U and Mandt, KE and Petrinec, SM and Raghuram, S and Reme, H and Rinaldi, M and Rubin, M and Semon, T and Trattner, KJ and Tzou, C-Y and Vigren, E and Waite, JH and Wurz, P},
doi = {0004-6361/201526210},
journal = {Astronomy & Astrophysics},
title = {ROSINA/DFMS and IES observations of 67P: Ion-neutral chemistry in the coma of a weakly outgassing comet},
url = {http://dx.doi.org/10.1051/0004-6361/201526210},
volume = {583},
year = {2015}
}
RIS format (EndNote, RefMan)
TY - JOUR
AB - Context. The Rosetta encounter with comet 67P/Churyumov-Gerasimenko provides a unique opportunity for an in situ, up-closeinvestigation of ion-neutral chemistry in the coma of a weakly outgassing comet far from the Sun.Aims. Observations of primary and secondary ions and modeling are used to investigate the role of ion-neutral chemistry within thethin coma.Methods. Observations from late October through mid-December 2014 show the continuous presence of the solar wind 30 km fromthe comet nucleus. These and other observations indicate that there is no contact surface and the solar wind has direct access tothe nucleus. On several occasions during this time period, the Rosetta/ROSINA/Double Focusing Mass Spectrometer measured thelow-energy ion composition in the coma. Organic volatiles and water group ions and their breakup products (masses 14 through 19),CO+, and CO+2(masses 28 and 44) and other mass peaks (at masses 26, 27, and possibly 30) were observed. Secondary ions includeH3O+and HCO+(masses 19 and 29). These secondary ions indicate ion-neutral chemistry in the thin coma of the comet. A relativelysimple model is constructed to account for the low H3O+/H2O+and HCO+/CO+ratios observed in a water dominated coma. Resultsfrom this simple model are compared with results from models that include a more detailed chemical reaction network.Results. At low outgassing rates, predictions from the simple model agree with observations and with results from more complex modelsthat include much more chemistry. At higher outgassing rates, the ion-neutral chemistry is still limited and high HCO+/CO+ratiosare predicted and observed. However, at higher outgassing rates, the model predicts high H3O+/H2O+ratios and the observed ratiosare often low. These low ratios may be the result of the highly heterogeneous nature of the coma, where CO and CO2 number densitiescan exceed that of water.
AU - Fuselier,SA
AU - Altwegg,K
AU - Balsiger,H
AU - Berthelier,JJ
AU - Bieler,A
AU - Briois,C
AU - Broiles,TW
AU - Burch,JL
AU - Calmonte,U
AU - Cessateur,G
AU - Combi,M
AU - De,Keyser J
AU - Fiethe,B
AU - Galand,M
AU - Gasc,S
AU - Gombosi,TI
AU - Gune,H
AU - Hansen,KC
AU - Haessig,M
AU - Jaeckel,A
AU - Korth,A
AU - Le,Roy L
AU - Mall,U
AU - Mandt,KE
AU - Petrinec,SM
AU - Raghuram,S
AU - Reme,H
AU - Rinaldi,M
AU - Rubin,M
AU - Semon,T
AU - Trattner,KJ
AU - Tzou,C-Y
AU - Vigren,E
AU - Waite,JH
AU - Wurz,P
DO - 0004-6361/201526210
PY - 2015///
SN - 1432-0746
TI - ROSINA/DFMS and IES observations of 67P: Ion-neutral chemistry in the coma of a weakly outgassing comet
T2 - Astronomy & Astrophysics
UR - http://dx.doi.org/10.1051/0004-6361/201526210
UR - http://hdl.handle.net/10044/1/28757
VL - 583
ER -