Jet power extracted from ADAF and the applications to X-ray binaries and radio galaxy FR dichotomy

We calculate the jet power of the classical Blandford-Znajek (BZ) model and hybrid model developed by Meier (2001) based on the global solutions of advection dominated accretion flows (ADAFs) surrounding Kerr black holes. We find that the jet power of the hybrid model is larger than that of the pure BZ model. The jet power will dominate over the accretion power and the objects will enter into “jet power dominated advective systems”, when the accretion rate is less than a critical value ṁc = Ṁc/ṀEdd, where 3× 10 −4 . ṁc . 5× 10 −3 is a function of black hole spin parameter. The accretion power will be dominant when ṁ & ṁc and the objects will enter into “accretion power dominated advective systems”. This is roughly consistent with that constrained from the low/hard state black hole X-ray binaries (e.g., Fender et al.). We calculate the maximal jet power as a function of black hole mass with the hybrid jet formation model, and find it can roughly reproduce the dividing line of the Ledlow-Owen relation for FR I/II dichotomy in jet power-black hole(BH) mass plane (Qjet −MBH), if the dimensionless accretion rate ṁ ∼ 0.01 and BH spin parameter j ∼ 0.9 − 0.99 are adopted. This accretion rate ṁ ∼ 0.01 is consistent with that the critical accretion rate for the accretion mode transition of a standard disk to an ADAF constrained from the state transition of X-ray binaries. Our results imply that most FR Is may be in the ADAF accretion mode similar to the low/hard state XRBs. Subject headings: accretion, accretion disks-black hole physics-galaxies: jets–Xrays: binaries-MHD International Center for Astrophysics, Korean Astronomy and Space Science Institute, Daejeon 305348, Republic of Korean; Email: [email protected] Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai, 200030 China Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USTC, 80 Randan Road, Shanghai 200030, China