Gas rotation and turbulence in the galaxy cluster Abell 2029

We constrain the rotation and turbulent support of the intracluster medium (ICM) in Abell 2029 (A2029) using dynamical equilibrium models and a combination of state-of-the-art X-ray datasets. The rotating turbulent ICM in the model has a composite polytropic distribution in equilibrium in a spherically symmetric, cosmologically motivated dark halo. The profile of rotation velocity and the distribution of turbulent velocity dispersion are described with flexible functional forms, which is consistent with the properties of synthetic clusters formed in cosmological simulations. Adopting realistic profiles for the metallicity distribution of the ICM and for the point spread function of XRISM and XMM-Newton, we tuned the observables of the intrinsic quantities of the plasma in our model via a Markov chain Monte Carlo algorithm to reproduce the radial profiles of the thermodynamic quantities as derived from the spectral analysis of the XMM-Newton and Planck maps and the measurements of the line-of-sight (LOS) nonthermal velocity dispersion and redshift (probing the LOS velocity) in the XRISM pointings. Our model accurately reproduces the measurements of redshift and LOS nonthermal velocity dispersion, and this was further demonstrated by simulating and analyzing synthetic counterparts of the XRISM spectra, in accordance with the posterior distributions we obtained. We measured the turbulence-to-total pressure ratio to be ≈ 2% across the 0 -- 650 kpc radial range, and under the hypothesis that rotation is the only bulk motion, we report a rotation-to-dispersion velocity ratio peaking at 0. 15 between 200 -- 600 kpc. The hydrostatic-to-total mass ratio is ≈ 0. 97 at r₂500, i. e. , the radius enclosing an overdensity of 2500 times the average value. Further constraints on the presence and amount of rotation could be obtained through a full azimuthal coverage of A2029 with XRISM.