اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدTracing Multiple Generations of AGN Feedback in the Core of Abell 262
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T. E. Clarke
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We present new radio and X-ray observations of Abell 262. The X-ray residual image provides the first evidence of an X-ray tunnel in this system while the radio data reveal that the central radio source is more than three times larger than previously known. We find that the well-known cluster-center S-shaped radio source B2 0149+35 is surrounded by extended emission to the east and south-west. The south-western extension is co-spatial with the X-ray tunnel seen in our new Chandra images while the eastern extension shows three clumps of emission with the innermost coincident with a faint X-ray cavity. The outer two eastern radio extensions are coincident with a newly detected X-ray depression. We use the projected separation of the emission regions to estimate a lower limit of tau_rep=28 Myr to the outburst repetition timescale of the central AGN. The total energy input into the cluster over multiple outburst episodes is estimated to be 2.2x 10^{58} ergs, more than an order of magnitude larger than previously thought. The total AGN energy output determined from our new observations shows that the source should be capable of offsetting radiative cooling over several outburst episodes.
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