Double-peaked Ca II traces a relativistic broad-line region disk in NGC 4593 M. W. Ochmann, P. M. Weilbacher, M. A. Probst, W. Kollatschny, D. Chelouche, R. Chini, D. Grupe, M. Haas, S. Kaspi and S. Komossa A&A, 697 (2025) L5 Published online: 14 May 2025 DOI: 10.1051/0004-6361/202554800