1. 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

2. 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

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

4. 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)

5. 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.

6. 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.

7. Sample properties

8. The fundamental plane relation

9. 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!

10. Evolution of BHFP

11. 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.

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

13. 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.

14. 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.

15. 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: keV
Calculated from optical spectra
Broad emission line AGNs

16. 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