2018MNRAS.481.1097M

We present here new insights about the merging galaxy cluster Abell 2034 ({bar}z=0.114) based on a combined weak lensing and dynamical analysis. From our deep Subaru BR_Cz^' images plus Gemini-GMOS/N low-resolution spectra accompanied by available redshift data, we have obtained the individual masses of the colliding subclusters as well as estimated a timeline of the process. The collision event happened 0.56^+0.15_–0.22 Gyr ago between the subclusters A2034S (M₂₀₀^S=2.35-0.99_^+0.84×10¹⁴ M_☉) and A2034N (M₂₀₀^N=^1.08-0.71_^+0.51 ×10¹⁴ M_☉) with the gas content of both subclusters displaced in relation to their galaxy and dark matter distributions, in a scenario similar to that found in the Bullet Cluster. Following our data and modelling the collision event is, most likely, taking place not so far from the plane of the sky, with an angle of 27° ± 14° in relation to that. In spite of the intrinsic degeneracy inherent to the system (whether it has been observed incoming or outgoing), the comparison of our calculated time since the closest approximation with the estimated age of the observed X-ray shock front and the increment experienced by the velocity dispersion of the galaxy cluster members point towards an outgoing movement. Besides, we found a strong evidence for the presence of a third structure that we called A2034W.