15
Some interesting Blazars observed by AGILE Valerio Vittorini (INAF-IASF Roma) on behalf of the AGILE Team and A. Paggi, A. Cavaliere (Univ. Tor Vergata)

Some interesting Blazars observed by AGILE

Embed Size (px)

DESCRIPTION

Some interesting Blazars observed by AGILE. Valerio Vittorini (INAF-IASF Roma) on behalf of the AGILE Team and A. Paggi, A. Cavaliere (Univ. Tor Vergata). AGN model. External: cosmological frame (z) radiation connected with accretion. - PowerPoint PPT Presentation

Citation preview

Page 1: Some interesting Blazars observed by  AGILE

Some interesting Blazars observed by AGILE

Valerio Vittorini (INAF-IASF Roma)

on behalf of the AGILE Team

and A. Paggi, A. Cavaliere (Univ. Tor Vergata)

Page 2: Some interesting Blazars observed by  AGILE

AGN model

Jet: jet-frame ( ) beamed, non thermal radiation

External: cosmological frame (z) radiation connected with accretion

Electron distribution ne(;b) and magnetic field Bproduce

Synchrotron + Inverse Compton (SSC)

External photons N’ext and ne(b) produce External Compton (EC)

Page 3: Some interesting Blazars observed by  AGILE

Synchrotron

External Compton

Self-Compton

Contribution to the SED

tdel

Page 4: Some interesting Blazars observed by  AGILE

Synchrotron

External Compton

Self-Compton

Variability patterns

rs=sF(s;t) / sF(s;t0)

rc=cF(c;t+tdel) / cF(c;t0+tdel)

tdel

Page 5: Some interesting Blazars observed by  AGILE

Synchrotron

External Compton

Self-Compton

Variability pattern: 0716+714

SSC signature!!

tdel

Page 6: Some interesting Blazars observed by  AGILE

The remarkable BL Lac 0716+714 (z=0.31) Sept - Oct 2007

• A very prominent BL Lac (S.Wagner et al. 1996; U. Bach et al. 2005)

• OVV

• Weak or absent disk component (no lines)

• BH mass uncertain, in the range 108-109 Msun

• detected by AGILE several times, including two of the strongest gamma-ray flare (so far) from a BL Lac

Page 7: Some interesting Blazars observed by  AGILE

PKS 0716+714

Page 8: Some interesting Blazars observed by  AGILE

AGILE-GRID, Sept. 2007

Page 9: Some interesting Blazars observed by  AGILE

The remarkable BL Lac 0716+714 (z=0.31)

Sept - Oct 2007

1) rvs ropt argues for SSC.

2) We need two components to account for the -flare and the complex

multi-band variability (see also Giommi et al. 08).

3) The day duration constraints

R < 5e16 (/20) cm, whereas

the very intense and hard spectrum and

the relative peaks position in the SED

require a II component with b > 6e3and 15.

4) The total jet power in the jet-frame

P = LB + Lkin + Lrad

exceeds 3e45 erg s-1cm-2

.

Figs. by Chen et al. 2008

Page 10: Some interesting Blazars observed by  AGILE

SED

Two components with

different and b. (black line is the sum)

Standard one-zone model

Vittorini et al. 2009 to appear in ApJ

1) the hardness of the -spectrum

2) the faint variability in hard-X ray accompanied by strong variations in the radio, optical and soft-X ray fluxes

Argue for a two-components model (see, e.g., Tavecchio & Ghisellini 2009)

Page 11: Some interesting Blazars observed by  AGILE

4x1045erg s-1

…that rises to 1046erg s-1 in the one component model

This is to be compared with the limit set by the Blandford-Znajek (1977) mechanism to the power extraction from a rotating BH:

Mrk 421

BL Lac

W Comae0716

Radiated luminosities

Observed fluxes

Courtesy of A. Paggi

and A. Cavaliere

Page 12: Some interesting Blazars observed by  AGILE

The remarkable FSRQ 3C 454 (z=0.859) Dec 2007

1) The wide, sinultaneous frequency coverageconstrains very well the model.

2) This state shows a moderate and soft IR-

optical bump with a strong and hard -ray

3) Low electron energies ( 300) are required by IR-Optical, UV and X-ray data, despite of the hard -ray spectrum

4) This requires a further component of hot (T 106 oK) seed photons entering on-side into the jet, maybe the hot corona

Donnarumma et al. 2009 to appear in ApJ

Page 13: Some interesting Blazars observed by  AGILE
Page 14: Some interesting Blazars observed by  AGILE

The remarkable BL Lac 0716+714 (z=0.31) Sept - Oct 2007

1) rvs ropt argues for SSC.

2) We need two components to account for the -flare and the complex multi-band variability (see also Giommi et al. 08).

3) The day duration constraints R < 5e16 (/20) cm, whereas

the very intense and hard spectrum and the relative peaks

position in the SED require a II component with b > 6e3 and 15.

4) with these ingredients the total jet power P = LB + Lkin + Lrad

exceeds 3e45 erg s-1cm-2 in the jet-frame.Figs. by Chen et al. 2008

Page 15: Some interesting Blazars observed by  AGILE