Building blocks of dust and large organic molecules: A coordinated laboratory and astronomical study of AGB stars

McCarthy, Michael C.

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https://hdl.handle.net/2142/96793 Copy

Description

Title

Building blocks of dust and large organic molecules: A coordinated laboratory and astronomical study of AGB stars

Author(s)

McCarthy, Michael C.

Contributor(s)

• Cernicharo, Jose
• Gottlieb, Carl A.

Issue Date

2017-06-22

Keyword(s)

Atacama Large Millimeter/submillimeter Array (ALMA)'s molecular view

Abstract

begin{wrapfigure}{r}{0pt}_x000d_ includegraphics[scale=0.65]{IRC.eps}_x000d_ end{wrapfigure} _x000d_ _x000d_ _x000d_ The increased sensitivity and angular resolution of high-altitude ground-based interferometers in the sub-millimeter band has enabled the physics and chemistry of carbon- and oxygen-rich evolved stars to be re-examined at an unprecedented level of detail. Observations of rotational lines in the inner envelope — the region within a few stellar radii of the central star where the molecular seeds of dust are formed — allows one to critically assess models of dust growth. Interferometric observations of the outer envelope provide stringent tests of neutral and ionized molecule formation. All of the astronomical studies are crucially dependent on precise laboratory measurements of the rotational spectra of new species and of vibrationally excited levels of known molecules and their rare isotopic species. By means of a closely coordinated laboratory and astronomical program, a number of exotic species including the disilicon carbide SiCSi, titanium oxides TiO and TiO$_2$, and carbon chain anions ranging from CN$^-$ to C$_8$H$^-$ have recently been observed in evolved stars. This talk will provide overview of these findings, and how they impact current models of the ``chemical laboratories'' of evolved stars. Ongoing laboratory studies of small silicon-bearing molecules such as H$_2$SiO$_2$ and vibrationally excited SiC$_2$ will be highlighted.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

text

Language

eng

Permalink

http://hdl.handle.net/2142/96793

DOI

https://doi.org/10.15278/isms.2017.RF06

Copyright and License Information

Copyright 2017 Michael C. McCarthy

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