Cross-checking SMBH mass estimates in NGC 6958-I. Stellar dynamics from adaptive optics-assisted MUSE observations
Journal article, 2022

Supermassive black hole masses (M (BH)) can dynamically be estimated with various methods and using different kinematic tracers. Different methods have only been cross-checked for a small number of galaxies and often show discrepancies. To understand these discrepancies, detailed cross-comparisons of additional galaxies are needed. We present the first part of our cross-comparison between stellar- and gas-based M-BH estimates in the nearby fast-rotating early-type galaxy NGC 6958. The measurements presented here are based on ground-layer adaptive optics-assisted Multi-Unit Spectroscopic Explorer (MUSE) science verification data at around 0."6 spatial resolution. The spatial resolution is a key ingredient for the measurement and we provide a Gaussian parametrization of the adaptive optics-assisted point spread function for various wavelengths. From the MUSE data, we extracted the stellar kinematics and constructed dynamical models. Using an axisymmetric Schwarzschild technique, we measured an M-BH of (3.6(-2.4)(+2.7)) x10(8) M-circle dot at 3 sigma significance taking kinematical and dynamical systematics (e.g. radially varying mass-to-light ratio) into account. We also added a dark halo, but our data do not allow us to constrain the dark matter fraction. Adding dark matter with an abundance matching prior results in a 25 per cent more massive black hole. Jeans anisotropic models return M-BH of (4.6(-2.7)(+2.5)) x10(8) and (8.6(-0.8)(+0.8)) x10(8) M-circle dot at 3 sigma confidence for spherical and cylindrical alignments of the velocity ellipsoid, respectively. In a follow-up study, we will compare the stellar-based M (BH) with those from cold and warm gas tracers, which will provide additional constraints for the M-BH for NGC 6958, and insights into assumptions that lead to potential systematic uncertainty.

galaxies: kinematics and dynamics

galaxies: individual: NGC 6958

galaxies: nuclei

Author

Sabine Thater

University of Vienna

Leibniz Institute for Astrophysics Potsdam

Davor Krajnovic

Leibniz Institute for Astrophysics Potsdam

Peter M. Weilbacher

Leibniz Institute for Astrophysics Potsdam

Dieu D. Nguyen

Vietnam National University

Martin Bureau

Yonsei University

University of Oxford

Michele Cappellari

University of Oxford

Timothy A. Davis

Cardiff University

Satoru Iguchi

National Institutes of Natural Sciences

Richard McDermid

Macquarie University

Kyoko Onishi

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Marc Sarzi

Armagh Observatory and Planetarium

Glenn van de Ven

University of Vienna

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 509 4 5416-5436

Subject Categories

Subatomic Physics

Astronomy, Astrophysics and Cosmology

Geophysics

DOI

10.1093/mnras/stab3210

More information

Latest update

5/25/2022