NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-06-16 T20:13:35 PDT
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For refcode 2017ApJ...836..104X:
Retrieve 75 NED objects in this reference.
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Copyright by American Astronomical Society. Reproduced by permission
2017ApJ...836..104X Fundamental Plane of Black Hole Activity in the Quiescent Regime Xie, Fu-Guo; Yuan, Feng Abstract. A correlation among the radio luminosity ({L}_{{R_}}), X-ray luminosity ({L}_{{X_}}), and black hole (BH) mass ({M}_{BH_}) in active galactic nuclei (AGNs) and BH binaries is known to exist and is called the "fundamental plane" of BH activity. Yuan & Cui predict that the radio/X-ray correlation index, {xi}_{{X_}}, changes from {xi}_{{X_}}~ 0.6 to {xi}_{{X_}}~ 1.2{--}1.3 when {L}_{{X_}}/{L}_{Edd_} decreases below a critical value of ~ {10}^-6^. While many works favor such a change, there are also several works claiming the opposite. In this paper, we gather from the literature the largest quiescent AGN (defined as {L}_{{X_}}/{L}_{Edd_}<~ {10}^-6^) sample to date, consisting of 75 sources. We find that these quiescent AGNs follow a {xi}_{{X_}}~ 1.23 radio/X-ray relationship, in excellent agreement with the Yuan & Cui prediction. The reason for the discrepancy between the present result and some previous works is that their samples contain not only quiescent sources but also "normal" ones (i.e., {L}_{{X_}}/{L}_{Edd_}>~ {10}^-6^). In this case, the quiescent sources will mix up with those normal ones in {L}_{{R_}} and {L}_{{X_}}. The value of {xi}_{{X_}} will then be between 0.6 and ~1.3, with the exact value being determined by the sample composition, i.e., the fraction of the quiescent and normal sources. Based on this result, we propose that a more physical way to study the fundamental plane is to replace {L}_{{R_}} and {L}_{{X_}} with {L}_{{R_}}/{L}_{Edd_} and {L}_{{X_}}/{L}_{Edd_}, respectively. Key words: accretion, accretion disks, black hole physics, galaxies: active, methods: statistical
Retrieve 75 NED objects in this reference.
Please click here for ADS abstract

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