The black hole fundamental plane: revisit with a larger sample of radio and X-ray emitting broad line AGNs Zhao-Yu Li Astronomy Department, Peking University Cooperator: Ran Wang Supervisor: Prof. Xue-Bing Wu

Outline Introduction The Radio And X-ray Emitting Broad Line AGN Sample Sample selection Sample properties Correlation Analysis The fundamental plane relation Statistical test for fundamental plane relation Evolution of the black hole fundamental plane Discussion

Introduction Accretion process is the key mechanism for a black hole to become active. The system is usually accompanied by a relativistic jet.

Previous work Brinkmann, Yuan & Siebert (1997) obtained a remarkable correlation between 2keV X-ray luminosity and 5GHz radio luminosity. Canosa et al. (1999) found a strong correlation between X-ray and 5GHz luminosities. Brinkmann et al. (2000) found radio and X-ray luminosity are strongly correlated. LR ∝ LX 0.7 (Gallo, Fender & Pooley 2003)

Introduction In a comprehensive study, Merloni et al. (2003) examined a sample combining GBH and SMBH by investigating their compact emission in X-ray (2-10keV) and radio (5GHz) bands. Wang et al. (2006) selected a uniform sample of 115 broad line AGNs which is cross-identified from the ROSAT All-Sky Survey, Sloan Digital Sky Survey (SDSS) and FIRST 20cm radio survey to test the black hole fundamental plane.

Sample selection Our sample is selected from the X-ray-emitting SDSS AGN catalog (Anderson et al. 2007) and the FIRST 20cm radio survey catalog. There are 725 objects in our sample. 498 sources are radio-loud, and the rest 227 objects are radio-quiet. Benefits of the larger sample: The objects distributes in a larger range. There are enough sources in different redshift bins spanning a wide range of luminosity.

Sample properties

The fundamental plane relation

Statistical test for BHFP Partial correlation test The partial correlation of X and Y with the influence of Z variable excluded is calculated The scrambling test By randomly assigning the radio fluxes to objects in our subsamples, the Pearson correlation coefficient between LR and ξRXLX +ξRMMbh is calculated. The BHFP relation is true!

Evolution of BHFP

Evolution of BHFP Based on the jet dominate model given by Heinz (2004) In order to understand the weak evolution of ξRX andξRM We use the Green Bank 4.85GHz northern sky survey (GB6) catalog and searched in GB6 catalog for objects in our sample, and found 114 radio-loud sources observed at 6cm.

Discussion Some uncertainties The Doppler beaming effect. Selection biases. The simultaneous observations.

Discussion It is difficult to connect the radio properties with the black hole mass or accretion rate. Jet collimation and formation are still unclear. Recently, Heinz (2004) calculated the BHFP for jet-dominated situations, under the assumption that jet is scale-invariant in different black hole systems (GBHs and SMBHs). Their predicted values areξRX=1.42 and ξRM=0. What we got here for radio-loud subsamples are ξRX=1.50±0.08 and ξRM=－0.20±0.10.

Discussion For radio-quiet sources, the physical mechanism of radio and X-ray emission is somewhat more complicated. Mainly, two models are commonly accepted for X-ray emission: Radiative efficient accretion flow (high accretion rate) SSD, hot corona etc. Radiative inefficient accretion flow (low accretion rate) ADAF etc. Our conclusions are consistent with what given by Wang et al. (2006), that radiatively inefficient accretion flow model seems to be working in the center.

Discussion With different samples, one usually gets different statistical results. Sample Energy band Black hole mass Species Merloni et al. (2003) Radio:5GHz X-ray: 2-10keV Obtained from literatures GBHs and SMBHs Our sample Radio:1.4GHz X-ray: 0.1-2.4keV Calculated from optical spectra Broad emission line AGNs

Summary Radio-loud and radio-quiet sources have different BHFP coefficients Radio-loud: ξRX = 1.50, ξRM =-0.20 Radio-quiet: ξRX = 0.73, ξRM=0.31 We used statistical test to confirm our results. The evolution of BHFP. This can be understood in part by the possible evolution of radio spectral index. Theoretical explanation: Radio-loud: jet radiation dominate model Radio-quiet: radiative inefficient disk model