Third International ASTROD Symposiumon Laser Astrodynamics, Space Test of Relativity

and Gravitational-Wave Astronomy

Beijing, China, July 14 - 16, 2006

Supermassive

black hole mass

J.H. Fan, J.S. Zhang

Center for Astrophysics

Guangzhou University

Outline

1. Introduction

2. Method

3. Discussion

4. Summary

INTRODUCTION Observations show that some sources with parti

cular observational properties

RBLs LBLs

1) BL Lacertae objects--BLs,

XBLs HBLs

2) Flat Spectrum Radio Quasars—FSRQs

RBLs LBLs BL Lacertae objects XBLs HBLs

What is a BL Lac Object?

From surveys there are radio selected BL lacertae objects and X-ray selected objects. From SED, BL Lacertae objects can be divided into HBL (high-energy peaked ) and LBLs ( low-energy peaked (LBL) respectively (Giommi & Padovani 1994; Padovani & Giommi 1995).

What is an FSRQ?Optically violently variable quasars--OVVs, (m>1.0m) ( Penston & Cannon,1970) Kinman (1975) OVV

s tend to have steep optical spectra and be associated with compact variable radio sources which have flat radio spectra at GHz frequencies.

Highly polarized quasars--HPQs ( p>3.0%), (Moore and Stockman 1981, ApJ, 243 ) ,

45%Core-dominated quasars--CDQs ( R = Lc/Le > 1.0)….etc

Confusion

INTRODUCTION

BLAZARS (BL Lacs and FSRQs)

extragalactic objects with rapid variability, high luminosity, high and variable polari

zation, or superluminal motions.

Objects with one of the above properties BLAZARS

The term “blazar” was coined, half in jest, by Ed Speigel at the first conference on BL Lac objects in Pittsburg.

AGN ModelFob=pFin

=(,)

Standard Model for Blazar活动星系核的标准模型

吸积盘

宽线区

窄线区

喷流

黑洞

There a super-massive black hole at the center with an accretion disk surrounding the black hole. The charged particles within the accretion disk are ejected at near the speed of light, forming two relativistic jets perpendicular to the plane of the accretion disk.

The central black hole is the central engine. It plays an important role on the emission of blazars.

Supermassive BH

BL & FSRQs

Similarity???

Difference ???

Relationship between BLs and FSRQs

1. Gravitational Effect, BLs are the gravitational images of FSRQs

2. Evolution. FSRQs with emission line evolve into BLs

3. Different Classes

4. Different angles to the line of sight

5. Other…

Nobody can ignore the difference and similarity between BL and FSRQs.

Their relationship has drawn much attention(e.g., Sambruna et al. 1996; Fan 2002;Ciaramella et al.200

4)

The central black hole is very important, we try to determine the black hole masses, and investigate the difference of BH masses between them.

Mass Determination

1. The broad-line width technique (Wandel & Yahil 1985)

Based on the assumption that Hβline velocity widths are gravitationally induced and orbit with Keplerian velocities.

Using the Hβluminosity to estimate the distance of the broad-line region (BLR) from the central source.

Mass Determination2. The reverberation mapping technique (e.g.

Wandel et al. 1999)

The size of the broad line region (BLR) can be measured from the time delay between the flux variations of the continuum and the emission lines of AGNs. The black hole mass is then estimated using the Virial theorem from the BLR size and the characteristic velocity (determined by the full width at half-maximum (FWHM) of the emission line). So far,

reverberation studies have yielded the black hole masses of about 20 Seyfert 1 galaxies and 17 nearby bright quasars.

Our considerations

*: The above methods are good for the nearby objects since we want to do observation of their emission clouds’ motion. For high redshift sources, they are not valid.

1 The central black hole masses of high redshift. Blazars have high redshifts.

2. Difference in BH masses between BL and FSRQs

3. We choose gamma-ray loud blazars

New Method--astro-ph/0503699

Considerations1. The -ray observations suggest that the

-rays are strongly boosted

2. -ray emission suggests that the optical depth of - pair production should not be larger than unity.

3. The observed short-time scale gives some information about the size of -ray emitting region.

4. The -ray emissions are from a cone with a solid angle Ω

Equation—1 Based on a paper by Becker & Kafatos(1995)

Equation-2 Based on the time Scale

T is in Days

Equation-3 Based on the beamed and unisot

ropic -ray Luminosity

)100(

)cos1(22 MeVFDL obsobs

Variables

7M

d

Observations

XX

D

F

T

L

,

,

Equation-4 Based on the minimum of Equation 1

Equations

………….. Eq (A)

…………….. Eq (B)

……….. Eq (C)

………….. Eq (D)

Sample

23 -ray loud blazars

11 BLs 12 FSRQs

Calculation Results

Mass Distribution for BL (solid line) and FSRQs (dotted line)

Results

log M|BL= (8.13+/-0.46) solar masses

log M|Q = (8.06+/-0.54) solar masses

Comparison

For 0420-014

1. Log M = 8.0--- 8.2 Our Results

2. Log M = 9.0

Woo & Urry 2002, ApJ

Comparison

For 3C 273

1. Log M = 7.90--- 8.07 Our Results

2. Log M = 7.11—7.70

Wang et al. 1996, ApJ

Comparison

For 3C 279

1. Log M = 7.6---8.0 Our result

2. Log M = 8.43 Woo & Urry 2002, ApJ

3. Log M = 8.4 Xie et al. 2005, PASJ

Comparison

For 1510-089

1. Log M = 8.40--- 8.6 Our Results

2. Log M = 8.65

Woo & Urry, 2002, ApJ

3. Log M = 8.1

Xie et al. 2005, PASJ

Conclusions

1. Masses are in the range of 10^(7-9) solar masses. Our results are consistent with others’.

2. The is no BH mass difference between BL and FSRQS

3. BH Masses do not play an important role in the evolution between BLs and FRSQs if there is an evolution from FSRQs to BLs

4. Or there is no evolution between BLs and FSRQs.

Thanks a lot

M87 3*109 Yuan Y.F. et al. 2005, in this proceeding

NGC

Kalpha to estimate mass (Yuan Y.F. et al. 2005, in this proceeding)