We analyse the environment of the supermassive black hole (SMBH) in the centre of a massive elliptical galaxy NGC 1275 in the Perseus cluster, hosting the radio source 3C 84. We focus on the young radio lobe observed inside the estimated Bondi accretion radius, and discusss the momentum balance between the jet associated with the lobe and the surrounding gas. The results are compared with the proper motion of the radio lobe obtained with the very long baseline interferometry. We find that under assumption of a high-density environment ( ≳ 100 cm−3), the jet power must be comparable to the Eddington luminosity – this is clearly inconsistent with the current moderate activity of 3C 84, which indicates instead that the jet is expanding in a very low-density region ( ≲ 1 cm−3), along the rotation axis of the accretion flow. The power required for the jet to expand in the low-density environment is comparable to the past average jet power estimated from the X-ray observations. We estimate the classical Bondi accretion rate, assuming that (1) gas accretion is spherically symmetric, (2) accretion is associated with the jet environment, and (3) the medium surrounding the jet is representative of the properties of the dominant accreting gas. We find that Bondi accretion is inconsistent with the estimated jet power. This means that either accretion of the cold gas in the NGC 1275 is more efficient than that of the hot gas, or the jets are powered by the SMBH spin.
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This work was supported by International Joint Research Promotion Program and Challenge Support Program by Osaka University. This work was also supported by KAKENHI (YF: 15K05080). NK acknowledges the financial support of Grant-in-Aid for Young Scientists (B:25800099). IS acknowledges partial support from the NSF and STScI. STScI is operated by AURA, Inc., under NASA contract NAS 5-26555. HI acknowledges the financial support of Grant-in-Aid for Young Scientists (B:26800159).
Fujita, Yutaka; Kawakatu, Nozomu; Shlosman, Isaac; and Ito, Hirotaka, "The Young Radio Lobe of 3C 84: Inferred Gas Properties in the Central 10 PC" (2015). Physics and Astronomy Faculty Publications. 456.