Detection of Two Interstellar Polycyclic Aromatic Hydrocarbons via Spectral Matched Filtering

Abstract

Ubiquitous unidentified infrared emission bands are seen in many astronomical sources. Although these bands are widely, if not unanimously, attributed to the collective emission from polycyclic aromatic hydrocarbons, no single species from this class has been detected in space. We present the discovery of two -CN functionalized polycyclic aromatic hydrocarbons, 1- and 2-cyanonaphthalene, in the interstellar medium aided by spectral matched filtering. Using radio observations with the Green Bank Telescope, we observe both bi-cyclic ring molecules in the molecular cloud TMC-1. We discuss potential in situ gas-phase formation pathways from smaller organic precursor molecules.

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Cited by in corpus (7)

• Discovery of benzyne, o-C6H4, in TMC-1 with the QUIJOTE line survey
• Discovery of two isomers of ethynyl cyclopentadiene in TMC-1: Abundances of CCH and CN derivatives of hydrocarbon cycles
• Machine Learning of Interstellar Chemical Inventories
• Discovery of Interstellar trans-cyanovinylacetylene (HCCCH=CHCN) and vinylcyanoacetylene (H${}_2$C=CHC${}_3$N) in GOTHAM Observations of TMC-1
• Intermediate-size fullerenes as degradation products of interstellar PAHs
• Deuterated Polycyclic Aromatic Hydrocarbons in the Interstellar Medium: The C--D Band Strengths of Multi-Deuterated Species
• Polycyclic aromatic hydrocarbons and the ionized gas