Constraining the AGN duty cycle in the cool-core cluster MS 0735.6+7421 with LOFAR data

Abstract

MS 0735.6+7421 is a galaxy cluster which hosts a central radio galaxy with a very steep spectrum, produced by one of the most powerful known jetted active galactic nuclei (AGN). The radio plasma, ejected at nearly light speed from the central AGN, have displaced the intra-cluster medium, leaving two pairs of cavities observable in the X-ray, associated to two different outbursts, and have distributed energy to the surrounding medium. In this work we have performed for the first time a detailed, high-resolution spectral study of the source at radio frequencies and investigated its duty cycle to be compared with previous X-ray estimates. We have used new observations at 144 MHz produced with the LOw Frequency ARray (LOFAR) together with archival data at higher frequencies. At LOFAR frequency, the source presents two large outer radio lobes, wider than at higher frequencies, and a smaller Intermediate lobe located south-west of the core. A new inspection of X-ray data, allowed us to identify an intermediate cavity, associated with that lobe, indicating the presence of a further phase of jet activity. The radio lobes have a steep spectrum even at LOFAR frequencies, reaching ${\alpha }_{144}^{610}=2.9$ in the outer lobes and ${\alpha }_{144}^{610}=2.1$ in the Intermediate lobe. Fitting the lobe spectra using a single injection model of particle ageing, we derived a total age of the source between 170 and 106 Myr, in agreement with the buoyancy and sound crossing time-scales derived from X-ray data. We then reconstructed the duty cycle of the source. There were three phases of jet activity, with the AGN being active for most of the time with only brief quiescent phases, ensuring the repeated heating of the central gas. Finally, energetic estimates revealed that a source of additional pressure support must be present to sustain the bubbles against the pressure of the external medium.

18 pages, 12 figures; accepted for publication in A&A

References in corpus (22)

• The NumPy array: a structure for efficient numerical computation
• Heating Hot Atmospheres with Active Galactic Nuclei
• WSClean: an implementation of a fast, generic wide-field imager for radio astronomy
• The LOFAR Two-metre Sky Survey - I. Survey Description and Preliminary Data Release
• Diffuse Radio Emission from Galaxy Clusters
• Radio interferometric gain calibration as a complex optimization problem
• Luminosity function, sizes and FR dichotomy of radio-loud AGN
• A Very Deep Chandra Observation of the Galaxy Group NGC 5813: AGN Shocks, Feedback, and Outburst History
• Non-linear Kalman filters for calibration in radio interferometry
• The Energetics and Lifetimes of Local Radio Active Galactic Nuclei
• Cycling of the powerful AGN in MS 0735.6+7421 and the duty cycle of radio AGN in Clusters
• RAiSE III: 3C radio AGN energetics and composition
• Radio Galaxy Zoo: A Search for Hybrid Morphology Radio Galaxies
• Discovery of a giant radio fossil in the Ophiuchus galaxy cluster
• The flickering nuclear activity of Fornax A
• Radio spectral properties and jet duty cycle in the restarted radio galaxy 3C388
• The contribution of discrete sources to the sky temperature at 144 MHz
• Using Radio Bubbles to Constrain the Matter Content of AGN Jets
• Radio Lobes of Pictor A: an X-ray spatially resolved Study
• Spectral ageing in the era of big data: integrated vs resolved models
• Evidence of AGN feedback and sloshing in the X-ray luminous NGC 1550 galaxy group
• LOFAR MSSS: The Scaling Relation between AGN Cavity Power and Radio Luminosity at Low Radio Frequencies

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