Abstract Supermassive black hole (SMBH) masses can be measured using molecular gas kinematics. Here we present high angular resolution (0. 12 arcsec or ≈11 pc) Atacama Large Millimeter/submillimeter Array observations of the 12CO (2–1) line emission of the early-type galaxy NGC 1387. The observations reveal a face-on, regularly-rotating central molecular gas disc with a diameter of ≈18 arcsec (≈1. 7 kpc) and a central depression slightly larger than the SMBH sphere of influence. We forward model the CO data cube in a Bayesian framework with the Kinematic Molecular Simulation code, and use Hubble Space Telescope data to constrain the stellar gravitational potential contribution to the molecular gas kinematics. We infer a SMBH mass of 1. 10^+1. 71-₀. ₉₅stat, 3 ^+2. 45-₁. ₀₉sys 10⁸ M⊙ and a F160W-filter stellar mass-to-light ratio of 0. 90^+0. 44-₀. ₃₅stat, 3 ^+0. 46-₀. ₃₆sys M⊙/L⊙, F160W. This SMBH mass is consistent with the SMBH mass – stellar velocity dispersion relation.
Dominiak et al. (Thu,) studied this question.