GBT19B-116

Continuing A GBT Census of Aromatic Molecules Outside TMC-1

Abstract

We have very recently reported the first detection of benzonitrile (C6H5CN) in TMC-1, using the GBT. Benzonitrile is the largest molecule ever seen by radio astronomy, and the first to contain a benzene ring (a six membered, aromatic carbon ring). Benzene rings are the the foundational structural elements of the ubiquitous polycyclic aromatic hydrocarbons (PAHs), as well as fullerenes like C60+, the only confirmed carrier of a diffuse interstellar band (DIB). Indeed, benzonitrile, as we have recently shown in the laboratory, is a direct chemical tracer of benzene. To assess the ubiquity and detectability of benzonitrile, and better understand its chemistry in the broader context of galactic chemical evolution, we are proposing a targeted survey of likely candidate sources for detection beyond TMC-1. Understanding the prevalence of benzonitrile, and thus the chemistry of benzene rings in the ISM at large, is critical not only to our ability to provide insight into yet larger molecules like PAHs and fullerenes, but to long-standing mysteries like the DIBs.

Investigators

Name	Institution
Brett McGuire *	National Radio Astronomy Observatory; Massachusetts Institute of Technology
Andrew Burkhardt	Center for Astrophysics | Harvard & Smithsonian; Wellesley College; Worcester State University
Ryan Loomis	National Radio Astronomy Observatory
Tony Remijan	National Radio Astronomy Observatory
Kin Long Kelvin Lee	Massachusetts Institute of Technology; Center for Astrophysics | Harvard & Smithsonian
Michael McCarthy	Center for Astrophysics | Harvard & Smithsonian

* indicates the PI