Imperial College London
Portrait Picture

Dr Ravindra T. Desai

Faculty of Natural Sciences, Department of Physics

Academic Visitor
 
 
 
//

Contact

 

ravindra.desai Website

 
 
//

Location

 

Blackett LaboratorySouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Desai:2017:2041-8213/aa7851,
author = {Desai, RT and Coates, AJ and Wellbrock, A and Vuitton, V and Crary, FJ and Gonzalez-Caniulef, D and Shebanits, O and Jones, GH and Lewis, GR and Waite, JH and Cordiner, M and Taylor, SA and Kataria, DO and Wahlund, J-E and Edberg, NJT and Sittler, EC},
doi = {2041-8213/aa7851},
journal = {Letters of the Astrophysical Journal},
title = {Carbon chain anions and the growth of complex organic molecules in titan's ionosphere},
url = {http://dx.doi.org/10.3847/2041-8213/aa7851},
volume = {844},
year = {2017}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Cassini discovered a plethora of neutral and ionized molecules in Titan's ionosphere including, surprisingly, anions and negatively charged molecules extending up to 13,800 u q−1. In this Letter, we forward model the Cassini electron spectrometer response function to this unexpected ionospheric component to achieve an increased mass resolving capability for negatively charged species observed at Titan altitudes of 950–1300 km. We report on detections consistently centered between 25.8 and 26.0 u q−1 and between 49.0–50.1 u q−1 which are identified as belonging to the carbon chain anions, CN−/C3N− and/or C2H−/C4H−, in agreement with chemical model predictions. At higher ionospheric altitudes, detections at 73–74 u q−1 could be attributed to the further carbon chain anions C5N−/C6H− but at lower altitudes and during further encounters extend over a higher mass/charge range. This, as well as further intermediary anions detected at >100 u, provide the first evidence for efficient anion chemistry in space involving structures other than linear chains. Furthermore, at altitudes below <1100 km, the low-mass anions (<150 u q−1) were found to deplete at a rate proportional to the growth of the larger molecules, a correlation that indicates the anions are tightly coupled to the growth process. This study adds Titan to an increasing list of astrophysical environments where chain anions have been observed and shows that anion chemistry plays a role in the formation of complex organics within a planetary atmosphere as well as in the interstellar medium.
AU  - Desai,RT
AU  - Coates,AJ
AU  - Wellbrock,A
AU  - Vuitton,V
AU  - Crary,FJ
AU  - Gonzalez-Caniulef,D
AU  - Shebanits,O
AU  - Jones,GH
AU  - Lewis,GR
AU  - Waite,JH
AU  - Cordiner,M
AU  - Taylor,SA
AU  - Kataria,DO
AU  - Wahlund,J-E
AU  - Edberg,NJT
AU  - Sittler,EC
DO  - 2041-8213/aa7851
PY  - 2017///
SN  - 2041-8205
TI  - Carbon chain anions and the growth of complex organic molecules in titan's ionosphere
T2  - Letters of the Astrophysical Journal
UR  - http://dx.doi.org/10.3847/2041-8213/aa7851
UR  - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000406276800001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR  - http://hdl.handle.net/10044/1/98353
VL  - 844
ER  -
Download