The large-scale shock in the cluster of galaxies Hydra A

Abstract

We analyzed a deep XMM-Newton observation of the cluster of galaxies Hydra A, focusing on the large-scale shock discovered as a surface brightness discontinuity in Chandra images. The shock front can be seen both in the pressure map and in temperature profiles in several sectors. The Mach numbers determined from the temperature jumps are in good agreement with the Mach numbers derived from EPIC/pn surface brightness profiles and previously from Chandra data and are consistent with M~1.3. The estimated shock age in the different sectors using a spherically symmetric point explosion model ranges between 130 and 230 Myr and the outburst energy between 1.5 and 3e61 ergs. The shape of the shock seen in the pressure map can be approximated with an ellipse centered 70 kpc towards the NE from the cluster center. We aimed to develop a better model that can explain the offset between the shock center and the AGN and give a consistent result on the shock age and energy. To this end, we performed 3D hydrodynamical simulations in which the shock is produced by a symmetrical pair of AGN jets launched in a spherical galaxy cluster. As an explanation of the observed offset of the shock center, we consider large-scale bulk flows in the intracluster medium. The simulation successfully reproduces the size, ellipticity, and average Mach number of the observed shock front. The predicted age of the shock is 160 Myr and the total input energy 3e61 erg. Both values are within the range determined by the spherically symmetric model. Matching the observed 70 kpc offset of the shock ellipse from the cluster center requires large-scale coherent motions with a high velocity of 670 km/s. We discuss the feasibility of this scenario and offer alternative ways to produce the offset and to further improve the simulation.

14 pages, accepted for publication in A&A, minor revision compared to previous version

References in corpus (10)

• A Catalog of Galaxy Clusters Observed by XMM-Newton
• A deeper X-ray study of the core of the Perseus galaxy cluster: the power of sound waves and the distribution of metals and cosmic rays
• Chemical enrichment in the cluster of galaxies Hydra A
• The XMM-Newton EPIC Background and the production of Background Blank Sky Event Files
• The answer is blowing in the wind: Simulating the interaction of jets with dynamic cluster atmospheres
• Metal-rich multi-phase gas in M87: AGN-driven metal transport, magnetic-field supported multi-temperature gas, and constraints on non-thermal emission observed with XMM-Newton
• Subgrid Modeling of AGN-Driven Turbulence in Galaxy Clusters
• Cool X-ray emitting gas in the core of the Centaurus cluster of galaxies
• Shock heating by FR I radio sources in galaxy clusters
• The abundance pattern of O, Mg, Si and Fe in the intracluster medium of the Centaurus cluster observed with XMM-Newton

Cited by in corpus (15)

• Abundance and temperature distributions in the hot intra-cluster gas of Abell 4059
• Discovery of a giant radio fossil in the Ophiuchus galaxy cluster
• Large-scale jets from active galactic nuclei as a source of ICM heating: cavities and shocks
• Physical properties of the X-ray gas as a dynamical diagnosis for galaxy clusters
• A New Class of X-Ray Tails of Early-Type Galaxies and Subclusters in Galaxy Clusters - Slingshot Tails vs Ram Pressure Stripped Tails
• Cavities, shocks and a cold front around 3C 320
• Long-term FRII jet evolution in dense environments
• AGN Feedback in Groups and Clusters of Galaxies
• On the Interaction of the PKS B1358-113 Radio Galaxy with the Abell 1836 Cluster
• Jet-Intracluster Medium interaction in Hydra A. I Estimates of jet velocity from inner knots
• A metal-rich elongated structure in the core of the group NGC4325
• Hyenas: X-ray Bubbles and Cavities in the Intra-Group Medium
• Gas-Phase metallicity for the Seyfert galaxy NGC 7130
• Accretion processes in the galaxy cluster Hydra A/Abell 780
• X-ray investigation of the remarkable galaxy group Nest200047