The dense warm ionized medium in the inner Galaxy W. D. Langer, J. L. Pineda, P. F. Goldsmith, E. T. Chambers, D. Riquelme, L. D. Anderson, M. Luisi, M. Justen and C. Buchbender A&A, 651 (2021) A59 Published online: 13 July 2021 DOI: 10.1051/0004-6361/202040223