Infrared Observations of Southern Classical Novae 1991 to 1992

TL;DR

This study monitored ten classical novae in the infrared to investigate dust formation, revealing that half produced dust and providing unique spectroscopic data, including the first CO fundamental emission observed in a nova.

Contribution

It presents the first spectroscopic observation of CO fundamental emission in a classical nova and offers comprehensive infrared spectra for several novae.

Findings

Five novae produced dust during outbursts.

First detection of CO fundamental emission in a nova.

Infrared spectra of V992 Sco and other novae provided.

Abstract

We report on a program to monitor classical novae (CNe) to determine if they produced dust in the ejecta created by their outbursts. Of the ten systems we followed, five produced dust. We also present limited infrared and optical spectroscopy of these objects. We present a complete $JHKLM$ spectrum for V992 Sco. V992 Sco was one of the brightest CNe in the infrared of all time, and our $M$-band spectrum of this object shows strong emission from the CO fundamental. We believe this to be the first, and only, spectroscopic observation of this feature in a CNe.