Cold fronts and metal anisotropies in the X-ray cool core of the galaxy
  cluster Zw1742+3306
  (Context) In recent years, our understanding of the cool cores of galaxy
clusters has changed. Once thought to be relatively simple places where gas
cools and flows toward the centre, now they are believed to be very dynamic
places where heating from the central Active Galactic Nucleus (AGN) and
cooling, as inferred from active star formation, molecular gas, and Halpha
nebulosity, find an uneasy energetic balance. (Aims) We want to characterize
the X-ray properties of the nearby cool-core cluster Zw1742+3306, selected
because it is bright at X-ray (with a flux greater than 1e-11 erg/s/cm2 in the
0.1-2.4 keV band) and Halpha wavelengths (Halpha luminosity > 1e40 erg/s).
(Methods) We used Chandra data to analyze the spatial and spectral properties
of the cool core of Zw1742+3306, a galaxy cluster at z=0.0757 that emits in
Halpha and presents the brightest central galaxy located in a diffuse X-ray
emission with multiple peaks in surface brightness. (Results) We show that the
X-ray cool core of the galaxy cluster Zw1742+3306 is thermodynamically very
active with evidence of cold fronts and a weak shock in the surface brightness
map and of an apparently coherent, elongated structure with metallicity greater
than the value measured in the surrounding ambient gas by about 50 per cent.
This anisotropic structure is 280 x 90 kpc2 and is aligned with the cold fronts
and with the X-ray emission on larger scales. We suggest that all these
peculiarities in the X-ray emission of Zw1742+3306 are either a very fine-tuned
output of a sloshing gas in the cluster core or the product of a metal-rich
outflow from the central AGN.
