N2+ fluorescence spectrum of comet C/2016 R2 (PanSTARRS) P. Rousselot, S. E. Anderson, A. Alijah, B. Noyelles, C. Opitom, E. Jehin, D. Hutsemékers and J. Manfroid A&A, 661 (2022) A131 Published online: 26 May 2022 DOI: 10.1051/0004-6361/202142829