The Fermi blazars The Fermi blazars dividedivide

Gabriele GhiselliniGabriele GhiselliniOsservatorio Astronomico di Brera

In collaboration with L. In collaboration with L. Maraschi and F. TavecchioMaraschi and F. Tavecchio

Bright Fermi blazarsBright Fermi blazars• >100 with >10>100 with >10 detection detection• 57 FSRQs and 42 BL Lacs57 FSRQs and 42 BL Lacs• Redshift for all FSRQs and for 30 Redshift for all FSRQs and for 30

BL LacsBL Lacs

Ghi

selli

ni, M

aras

chi,

Tave

cchi

o G

hise

llini

, Mar

asch

i, Ta

vecc

hio

2009

2009There is

a sequence

…

There is a se

quence…

-ra

y en

ergy

spe

ctra

l ind

ex

BL LacsBL Lacs

FSRQsFSRQs

TeV

Ghi

selli

ni, M

aras

chi,

Tave

cchi

o G

hise

llini

, Mar

asch

i, Ta

vecc

hio

2009

2009……desp

ite

despite

dramatic

dramatic

varia

bility

varia

bility

BL LacBL Lac

FerFermimi

454.3454.3

FerFermimi

AgilAgilee

05205288

FerFermimi

279279

FerFerm

im

i

MAGICMAGIC

Foss

ati e

t al

. 199

8; D

onat

o et

al.

Foss

ati e

t al

. 199

8; D

onat

o et

al.

2001

2001

TheThe “blazar“blazar sequence”sequence” FSRQsFSRQs

BL LacsBL Lacs

SteepSteep

FlatFlat

LL

Steep Steep FSRQsFSRQs

Flat BL Flat BL LacsLacs

The divideThe divide

The

blaz

ar d

ivid

eTh

e bl

azar

div

ide

~100~100

~100~100

PPjetjet~M~Maccraccrcc2 2 L Ldiskdisk>>~~

Celo

tti &

GG

200

8Ce

lott

i & G

G 2

008

Celo

tti &

GG

200

8,

Celo

tti &

GG

200

8, M

aras

chi+

200

8M

aras

chi+

200

8

Celo

tti &

GG

200

8,

Celo

tti &

GG

200

8, M

aras

chi+

200

8M

aras

chi+

200

8

GG

, Tav

ecch

io &

Ghi

rlan

da in

pre

p,

~100~100

LLdiskdisk~M~MEddEddcc22

LLdiskdisk~0.01M~0.01MEddEdd

cc22

PPjetjet~M~Maccraccrcc2 2 L Ldiskdisk>>~~

Ledl

ow &

Ow

enLe

dlow

& O

wen

Ghi

selli

ni &

Cel

otti

G

hise

llini

& C

elot

ti

2000

2000

Ghi

selli

ni &

Cel

otti

G

hise

llini

& C

elot

ti

2000

2000

Ledl

ow &

Ow

enLe

dlow

& O

wen

Disk accretion rate (Eddington Disk accretion rate (Eddington units)units)

LLdi

skdi

sk

PPje

tje

tJet power vs disk Lum.Jet power vs disk Lum.

e-p e-p decouplindecoupling g

Photon Photon trappingtrappingBL Lacs,

FSRQ

FRI,

FRII

~10~10-2-2

PP jetjet

LL diskdisk

Torus ~1-10 Torus ~1-10 pcpc

RRBLRBLR ~ L ~ Ldisk disk

UUBLRBLR= = constconst

1/21/2

RRTorusTorus~ L~ Ldisk disk

UUIRIR= const= const

1/21/2

strong coolingstrong coolingExternal ComptonExternal Compton

BLRBLRStandard

Standard

diskdisk

M>0.01MM>0.01MEdEd

dd

Far IRFar IR

MeVMeV

BLR <<0.2 BLR <<0.2 pcpc

RRBLRBLR ~ L ~ Lioniz ioniz

~No BLR ~No BLR (or very (or very small)small)

1/21/2

weak weak coolingcooling

SSC onlySSC onlyM<0.01MM<0.01MEE

dddd

TeVTeV

XX

TeVTeV

““ADAF disk”

ADAF disk”

Evolution? Evolution? (e.g. Cavaliere & D’Elia 2002)

• M should increase with redshiftM should increase with redshift• In the past more FSRQs (and In the past more FSRQs (and

FRII): positive evolution? FRII): positive evolution? • Now more BL Lacs (and FRI): Now more BL Lacs (and FRI):

negative evolution?negative evolution?• And taken together…? Similar to And taken together…? Similar to

radio-quiet or not?radio-quiet or not?

Conclusions/PredictionsConclusions/Predictions• The most powerful Fermi blazars The most powerful Fermi blazars

should be accreting near should be accreting near Eddington, and have the largest Eddington, and have the largest black hole massesblack hole masses

• Also radio-quiet should have much Also radio-quiet should have much weaker broad lines for M<0.01Mweaker broad lines for M<0.01MEddEdd

• As the survey goes on, including As the survey goes on, including weaker sources….weaker sources….

~forbidden

~forbidden

exce

pt

exce

pt

extra

ordinary

extra

ordinary

and ra

re sta

tes

and ra

re sta

tes

smaller M0948

Conclusions/PredictionsConclusions/Predictions• The most powerful Fermi blazars The most powerful Fermi blazars

should be accreting near should be accreting near Eddington, and have the largest Eddington, and have the largest black hole massesblack hole masses

• Also radio-quiet should have much Also radio-quiet should have much weaker broad lines for weaker broad lines for M<0.01MM<0.01MEddEdd

From Ho, 2008, ARAA.. For radio-quiet:From Ho, 2008, ARAA.. For radio-quiet:

“8. Low luminosity AGNs are not simply scaled-down versions of powerful AGNs. Their central engines undergo fundamental changes when the accretion rate << Eddington. In this regime, the BLR and obscuring torus disappear…

9. Below L~0.01% Eddington, the canonical accretion disk transforms into an inner vertically thick and radiatively inefficient accretion flow….”

MM22

MM

ADAFADAF (Narayan et (Narayan et al.)al.)

LLjetjet propto propto LLdiskdisk

1/21/2LLjet jet propto propto LLdiskdisk

By By modeling, modeling, we find we find physical physical parameters parameters in the in the comoving comoving frame.frame.

peakpeak is the is the energy of energy of electrons electrons emitting at emitting at the peak of the peak of the SEDthe SED

EGRET EGRET blazarsblazars

Low power slow cooling large peak

Big power Big power fast fast cooling cooling small small peakpeak

ttcoolcool 1/( 1/(peakpeak U) = R/c U) = R/c

peakpeakU = U = constconst

22

Power of jetsPower of jets

LLr r = radiation= radiationLLe e = relat. = relat. electronselectronsLLp p = protons= protonsLLB B = B-field= B-field RR

The power of blazar jetsThe power of blazar jets

~1017 cm

If one p per e-If one p per e-

Relat. Relat. electronselectrons

Magnetic FieldMagnetic Field

RadiationRadiation

Celo

tti &

Ghi

selli

ni

Celo

tti &

Ghi

selli

ni

2007

2007

High High powerpower

Powerful jets a

re not

Powerful jets a

re not

magnetically

dominated

magnetically

dominated

If one p per e-If one p per e-

Relat. Relat. electronselectrons

Magnetic FieldMagnetic Field

RadiationRadiation

Celo

tti &

Ghi

selli

ni

Celo

tti &

Ghi

selli

ni

2007

2007

Low powerLow power