Looking through the photoionisation wake: Vela X−1 at φorb ≈ 0.75 with Chandra/HETG R. Amato, V. Grinberg, N. Hell, S. Bianchi, C. Pinto, A. D’Aí, M. Del Santo, T. Mineo and Santangelo A&A, 648 (2021) A105 Published online: 21 April 2021 DOI: 10.1051/0004-6361/202039125