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New insight into Gamma-ray Blazars from the Fermi-LAT Benoît Lott CEN Bordeaux-Gradignan

New insight into Gamma-ray Blazars from the Fermi-LAT Benoît Lott CEN Bordeaux-Gradignan on behalf of the Fermi-LAT collaboration. Fermi-LAT as an all-sky monitor. OR103 FSRQ z=1.83 ATEL #1650 S.Ciprini et al. 3-month sky survey. TS=100, photon index=2.2.

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New insight into Gamma-ray Blazars from the Fermi-LAT Benoît Lott CEN Bordeaux-Gradignan

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  1. New insight into Gamma-ray Blazars from the Fermi-LAT Benoît Lott CEN Bordeaux-Gradignan on behalf of the Fermi-LAT collaboration

  2. Fermi-LAT as an all-sky monitor OR103 FSRQ z=1.83 ATEL #1650 S.Ciprini et al.

  3. 3-month sky survey TS=100, photon index=2.2 Flux(E>100 MeV) ph cm-2s-1

  4. Two flavors of blazars: FSRQs and BLLacs • Defining property: • strong emission lines • intense radiation field • (disk, clouds) • outside the jet • High power (~1046-48 erg/s) • Parent population: FRII • Low synchrotron npeak (IR) in SED • 46 FSRQs in EGRET all-sky survey (18 months) • high redshift 0.1 < z < 2.3

  5. Two flavors of blazars: FSRQs and BLLacs • from the “BL Lacerta” archetype • Defining property: nearly lineless • Low ambient radiation field • “Low” power (~1045-46 erg/s) • Parent population: FR I • Low npeak (Opt/IR): LBL • High npeak (UV/X-rays): HBL (TeV) • 14 BLLacs in EGRET all-sky survey • Low redshift 0< z < 0.9

  6. associations 0FGL:132 sources with TS>100, |b|>10° 7 pulsars, 125 AGN candidates CGRaBS(Healey et al. 08) 1627 radio sources from CRATES association based on Figure-of-Merit (spatial, radio and X spectrum) established from EGRET 101 high-conf. (P>90%) associations 14 low-conf. (40%<P<90%) associations BZCat (Massaro et al. 08) Compilation of 2500 known blazars association based on spatial coincidence (Mattox et al., 01) 102 high-conf. (P>90%) associations 4 low-conf. (40%<P<90%) associations galactic celestial

  7. LAT Bright AGN Sample (LBAS) 57 FSRQ 42 BLLac 6 of Uncertain class 2 Radio Galaxies Preliminary • 125 non-pulsar sources at |b|>10° • 106 high-confidence (P>90%) associations with AGNs: (LBAS) • 10 lower-confidence associations • FSRQs: 57 • BLLacs: 42 • Uncertain class: 5 • Radiogalaxies: Cen A, NGC1275 • 40% BLLacs (23% for EGRET) • 7 HBLs (3+1 for EGRET) • 9 unidentified (3EG: 96/181 at |b|>10°) Q95% ~0.14° (EGRET sample ~0.62°)

  8. Flux vs index Preliminary FSRQ BLLac Uncertain Radio Galaxies TS=100 b=20, 80 deg. TS=100 b= 20 deg. E< 3 GeV

  9. Flux distributions Preliminary weekly peak flux mean flux Fermi EGRET EGRET mean flux « 1234 VP» EGRET peak flux: maximum in 2-w VPs Fermi mean flux: 3-m averaged Fermi peak flux: maximum in 1-w periods peak/mean flux ratio mean vs peak flux

  10. SED at LAT energies Preliminary 3C454.3 (FSRQ) AO 0235+165 (Int. BL) Mkn501 (HBL) Significant departures from pure power-law distributions for bright blazars!

  11. FSRQs nFn BLLacs n Photon index distributions Preliminary all FSRQs Number of sources <G>= 2.33±0.01 BL Lacs <G>=1.99±0.01 Photon index

  12. LBAS Sources in 3EG Preliminary EGRET vs FERMI photon index 33 AGNs/116 LAT-sources (30%) in 3EG catalog with a comparable flux → duty cycle Others are found at lower fluxes FSRQs: 20 BLLacs: 11 Uncertain: 3 Radio galaxy:1 FSRQ BLLac Uncertain Radio galaxies

  13. FSRQs BZCat LAT BL Lacs BZCat LAT Redshift distributions Preliminary Preliminary Mukherjee et al. 1999 EGRET FSRQ BLLac Uncertain Radio galaxies

  14. Log N - Log S Preliminary Preliminary FSRQs • « sky coverage » enables the log N-LogS to be computed • Euclidian space: slope=2.5 BL Lacs Marco Ajello

  15. Luminosity vs redshift Preliminary FSRQ BLLac Uncertain Radio galaxies

  16. <V/Vmax> test <V/Vmax>: ratio between the comoving volume within which the source was detected and the maximum volume available for its detection Population uniformly distributed in Euclidian space, non evolving: <V/Vmax> ~ 0.5 Preliminary Positive evolution for FSRQs (more FSRQs in the past) Compatible with no evolution for BLLacs

  17. Perspectives • Luminosity function • Contribution of unresolved blazars to Extragalactic Diffuse Background • Variability on different timescales • Duty cycle of blazars • Existence of a blazar sequence ? (evolutionary link between FSRQs and BLLacs?) • Gamma-ray radio connection • …

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