2025/11/29 by Srivastava, Alpish, Reiprich, Thomas H., Veronica, Angie +4
#Astrophysics of Galaxies (astro-ph.GA) #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences
paper · doi:10.48550/arxiv.2512.00518
The Hydra I galaxy cluster (Abell 1060) is a nearby example of a low-temperature cluster that exhibits intermediate cool core and non-cool core properties. We aim to extend the characterization of the intracluster medium (ICM) properties at least until R200 and study the correlation between the X-ray emission and non-thermal emission within R=0.15R500, and optical/IR galaxy distribution beyond R200. We used data from the first four SRG/eROSITA All-Sky Surveys and an archival Chandra observation to image the X-ray emission from Abell 1060. We also used multiwavelength data from TGSS (radio), 2MASS (IR), and NED (optical) to investigate the non-thermal emission, 2D galaxy distribution, and its redshift evolution, respectively. The surface brightness and spectral analyses are also extended until 3R200 and R200, respectively, following a detailed cosmic X-ray background (CXB) analysis. Our fully corrected eROSITA image showcases a relaxed ICM morphology within R500. We detect two weak ICM shocks with Mach number M≈ 1.5 near the central galaxy NGC 3311 that coincide with diffuse radio emission along the line of sight. Furthermore, we detect multiple soft X-ray excesses with high spatial correlation with the 2D optical galaxy distribution beyond R200. In particular, the excess in the north has a significance of 5.8σ above the local CXB level. This suggests that Abell 1060's outskirts are actively accreting baryons. We also estimate the average ICM temperature and metallicity of ⟨ kBT ⟩=2.27\substack+0.15 -0.11\thinspace keV and ⟨ Z⟩=0.19\substack+0.05 -0.03\thinspace Z_\odot, respectively, from the 0.2-0.5R500 annulus. Overall, the temperature profile is broadly consistent with the average temperature profiles from hydrodynamical simulation and Suzaku between 0.28R200 and R200.