C2N2 vertical profile in Titan's stratosphere

Melody A S Sylvestre; Nicholas A  Teanby; M. Dobrijevic; Jason Sharkey; Patrick G. J. Irwin

doi:10.3847/1538-3881/abafb2

C₂N₂ vertical profile in Titan's stratosphere

Melody A S Sylvestre^*, Nicholas A Teanby, M. Dobrijevic, Jason Sharkey, Patrick G. J. Irwin

^*Corresponding author for this work

Research output: Contribution to journal › Article (Academic Journal) › peer-review

Abstract

In this paper, we present the first measurements of the vertical distribution of cyanogen (C₂N₂) in Titan’s lower atmosphere at different latitudes and seasons, us- ing Cassini/CIRS far-IR data. We also study the vertical distribution of three other minor species detected in our data: methylacetylene (C₃H₄), diacetylene (C₄H₂) and H₂O, in order to compare them to C₂N₂, but also to get an overview of their seasonal and meridional variations in Titan’s lower stratosphere from 85 km to 225 km. We measured an average volume mixing ratio of C₂N₂ of 6.2 ± 0.8 × 10⁻¹¹ at 125 km at the equator, but poles exhibit a strong enrichment in C₂N₂ (up to a factor 100 com- pared to the equator), greater than what was measured for C₃H₄ or C₄H₂ . Measuring C₂N₂ profiles provides constraints on the processes controlling its distribution, such as bombardment by Galactic Cosmic Rays which seem to have a smaller influence on C₂N₂ than predicted by photochemical models.

Original language	English
Article number	178
Number of pages	9
Journal	Astronomical Journal
Volume	160
Issue number	4
DOIs	https://doi.org/10.3847/1538-3881/abafb2
Publication status	Published - 21 Sep 2020

Access to Document

10.3847/1538-3881/abafb2

Embargoed Document

Full-text PDF (author’s accepted manuscript)
Accepted author manuscript, 543 KB
Embargo ends: 21/09/21
Request copy

Cite this

@article{bbf638b914664e70aee077fbb343b401,

title = "C2N2 vertical profile in Titan's stratosphere",

abstract = "In this paper, we present the first measurements of the vertical distribution of cyanogen (C2N2) in Titan{\textquoteright}s lower atmosphere at different latitudes and seasons, us- ing Cassini/CIRS far-IR data. We also study the vertical distribution of three other minor species detected in our data: methylacetylene (C3H4), diacetylene (C4H2) and H2O, in order to compare them to C2N2, but also to get an overview of their seasonal and meridional variations in Titan{\textquoteright}s lower stratosphere from 85 km to 225 km. We measured an average volume mixing ratio of C2N2 of 6.2 ± 0.8 × 10−11 at 125 km at the equator, but poles exhibit a strong enrichment in C2N2 (up to a factor 100 com- pared to the equator), greater than what was measured for C3H4 or C4H2 . Measuring C2N2 profiles provides constraints on the processes controlling its distribution, such as bombardment by Galactic Cosmic Rays which seem to have a smaller influence on C2N2 than predicted by photochemical models.",

author = "Sylvestre, {Melody A S} and Teanby, {Nicholas A} and M. Dobrijevic and Jason Sharkey and Irwin, {Patrick G. J.}",

year = "2020",

month = sep,

day = "21",

doi = "10.3847/1538-3881/abafb2",

language = "English",

volume = "160",

journal = "Astronomical Journal",

issn = "0004-6256",

publisher = "American Astronomical Society",

number = "4",

}

TY - JOUR

T1 - C2N2 vertical profile in Titan's stratosphere

AU - Sylvestre, Melody A S

AU - Teanby, Nicholas A

AU - Dobrijevic, M.

AU - Sharkey, Jason

AU - Irwin, Patrick G. J.

PY - 2020/9/21

Y1 - 2020/9/21

N2 - In this paper, we present the first measurements of the vertical distribution of cyanogen (C2N2) in Titan’s lower atmosphere at different latitudes and seasons, us- ing Cassini/CIRS far-IR data. We also study the vertical distribution of three other minor species detected in our data: methylacetylene (C3H4), diacetylene (C4H2) and H2O, in order to compare them to C2N2, but also to get an overview of their seasonal and meridional variations in Titan’s lower stratosphere from 85 km to 225 km. We measured an average volume mixing ratio of C2N2 of 6.2 ± 0.8 × 10−11 at 125 km at the equator, but poles exhibit a strong enrichment in C2N2 (up to a factor 100 com- pared to the equator), greater than what was measured for C3H4 or C4H2 . Measuring C2N2 profiles provides constraints on the processes controlling its distribution, such as bombardment by Galactic Cosmic Rays which seem to have a smaller influence on C2N2 than predicted by photochemical models.

AB - In this paper, we present the first measurements of the vertical distribution of cyanogen (C2N2) in Titan’s lower atmosphere at different latitudes and seasons, us- ing Cassini/CIRS far-IR data. We also study the vertical distribution of three other minor species detected in our data: methylacetylene (C3H4), diacetylene (C4H2) and H2O, in order to compare them to C2N2, but also to get an overview of their seasonal and meridional variations in Titan’s lower stratosphere from 85 km to 225 km. We measured an average volume mixing ratio of C2N2 of 6.2 ± 0.8 × 10−11 at 125 km at the equator, but poles exhibit a strong enrichment in C2N2 (up to a factor 100 com- pared to the equator), greater than what was measured for C3H4 or C4H2 . Measuring C2N2 profiles provides constraints on the processes controlling its distribution, such as bombardment by Galactic Cosmic Rays which seem to have a smaller influence on C2N2 than predicted by photochemical models.

U2 - 10.3847/1538-3881/abafb2

DO - 10.3847/1538-3881/abafb2

M3 - Article (Academic Journal)

VL - 160

JO - Astronomical Journal

JF - Astronomical Journal

SN - 0004-6256

IS - 4

M1 - 178