A First Chandra View Of The Cool Core Cluster A1668: Offset Cooling And Agn Feedback Cycle

We present a multiwavelength analysis of the cluster A1668, performed by means of new EVLA and Chandra observations and archival H alpha data. The radio images exhibit a small central source (similar to 14 kpc at 1.4 GHz) with L (1.4GHz) similar to 6 center dot 10(23) W Hz(-1). The mean spectral index between 1.4 GHz and 5 GHz is similar to-1, consistent with the usual indices found in BCGs. The cooling region extends for 40 kpc, with bolometric X-ray luminosity L (cool) = 1.9 +/- 0.1 center dot 10(43) erg s(-1). We detect an offset of similar to 6 kpc between the cluster BCG and the X-ray peak, and another offset of similar to 7.6 kpc between the H alpha and the X-ray peaks. We discuss possible causes for these offsets, which suggest that the coolest gas is not condensing directly from the lowest-entropy gas. In particular, we argue that the cool ICM was drawn out from the core by sloshing, whereas the H alpha filaments were pushed aside from the expanding radio galaxy lobes. We detect two putative X-ray cavities, spatially associated with the west radio lobe (cavity A) and the east radio lobe (cavity B). The cavity power and age of the system are P (cav) similar to 9 x 10(42) erg s(-1) and t (age) similar to 5.2 Myr, respectively. Evaluating the position of A1668 in the cooling luminosity-cavity power parameter space, we find that the AGN energy injection is currently consistent within the scatter of the relationship, suggesting that offset cooling is likely not breaking the AGN feedback cycle.