The cosmological evolution of blazars and the cosmic gamma- ray - PowerPoint PPT Presentation

The cosmological evolution of blazars and the cosmic gamma- ray background in the Fermi era Yoshiyuki INOUE (Kyoto, JSPS fellow DC1) Collabolators ： Tomonori Totani, Susumu Inoue (Kyoto), Masakazu. A. R. Kobayashi (NAO), Jun Kataoka (Waseda), Rie Sato (JAXA) Fermi Symposium 1

What’s the origin of the cosmic gamma-ray background? 1. MeV Background AGNs (Rogers & Field ’91; Field & Rogers ’93; E^2 dJ/dE (keV/cm^2/s/sr) Stecker, Salamon, & Done ’01; YI, Totani, & Ueda’08) Supernovae (Clayton & Ward ‘75; Zdziarski ‘96; Watanabe+‘99) MeV Dark Matter annihilation (Ahn & Komatsu ’06, Rasera+‘06; Lawson & Zhitnitsky ‘07 ) MeV Blazars (Ajello+’09) AGNs 2. GeV Background Blazars (Stecker & Salamon ’96; Chiang & Mukherjee ’98; Mücke & Pohl 00; Narumoto & Totani ’06; Dermer ’07; YI & Totani ’09) keV MeV GeV Galaxy Cluster Merger (Loeb & Waxman ‘00; Totani & Kitayama ’00) GeV Dark Matter annihilation (e.g. Oda et al. ’05) Energy (keV) Sreekumar et al. 1998 2

What is BLAZAR? SED Sequence 49 Blazar 48 47 Log 10 ( ν L ν [erg/s]) Log 10 � L � (erg s -1 ) 46 45 44 Inverse 43 Synchrotron Compton GeV 42 41 -5 0 5 10 Log 10 (Energy [eV]) Log 10 E � (eV) (Fossati+’97,’98; Kubo+’98; Donato http://www.nasa.gov/ +’01, but see also Padovani+’07) 3

Blazar Gamma-ray Luminosity Function (YI & Totani ’09) Basic assumptions for blazar GLF construction • Blazar SED sequence. • AGN X-ray Luminosity Function (Ueda+’03:hereafter U03) . Assuming “L jet, bol ∝ L disk, X “. Constraining GLFs from EGRET data. Redshift Distribution Luminosity Distribution 1.8 0.8 1.6 0.7 U03(q) U03(q) 1.4 0.6 U03(q, γ 1 ) U03(q, γ 1 ) dN/d(log 10 L γ ) 1.2 dN/log(L γ ) dN/log(z) dN/d(log 10 z) H05(q) H05(q) 0.5 H05(q, γ 1 ) 1 H05(q, γ 1 ) 0.4 EGRET blazars EGRET blazars 0.8 0.3 0.6 0.2 0.4 0.1 0.2 0 0 43 44 45 46 47 48 49 50 0.01 0.1 1 log(L γ [erg/s]) Redshift z 4 log 10 (L γ [erg s -1 ]) Redshift z

Cosmic X-ray and Gamma-ray Background before the Fermi era 10 -1 Blazar: U03 (q, γ 1 ) Non-blazar ( Γ =3.5): ITU08 E 2 dN/dE (MeV/cm 2 /s/sr) E 2 dN/dE (MeV 2 cm -2 s -1 MeV -1 sr -1 ) Non-blazar ( Γ =3.8): ITU08 Blazar + Non-blazar ( Γ =3.5) Blazar + Non-blazar ( Γ =3.8) HEAO-1 EGRET (S98) 10 -2 EGRET (S04a) Swift/BAT EGRET (S98+S08) SMM COMPTEL non-blazar AGNs 10 -3 (YI+08) Blazars ( YI & TT 09) X-ray MeV GeV 10 -4 10 -2 10 -1 10 0 10 1 10 2 10 3 10 4 10 5 10 6 Energy (MeV) YI & TT 09 Photon Energy (MeV) Above GeV, our model does not reproduce arXiv:0810.3580 observational data. 5

Cosmic X-ray and Gamma-ray Background in the Fermi era 10 -1 Blazar: U03 (q, � 1 ) Non-blazar ( � =3.5): ITU08 E 2 dN/dE (MeV 2 cm -2 s -1 MeV -1 sr -1 ) E 2 dN/dE (MeV/cm 2 /s/sr) Non-blazar ( � =3.8): ITU08 Blazar + Non-blazar ( � =3.5) Blazar + Non-blazar ( � =3.8) 10 -2 EGRET (S98) EGRET (S04a) EGRET (S98+S08) Fermi non-blazar Fermi Data from AGNs TeV conf. on July 10 -3 (YI+08) Blazars ( YI&TT09) X-ray MeV GeV 10 -4 10 -2 10 -1 10 0 10 1 10 2 10 3 10 4 10 5 10 6 Energy (MeV) Photon Energy (MeV) YI & TT 09 Our prediction matched very well arXiv:0810.3580 with the Fermi data. 6

Non-blazar AGNs vs. Blazars <~10 MeV: • smooth connection to CXB • likely to be non-blazar E 2 dN/dE (MeV/cm 2 /s/sr) AGNs Blazars >~10 MeV: • distinct SED from CXB Non-blazar • likely to be blazars AGNs • MeV-blazar contribution at <~10 MeV? (Ajello+09) • fine-tuning required for SED • distinct blazar population required between MeV and GeV. Ackermann+’09 at TeV. conf. Energy (MeV)

Expected Number of Fermi AGNs • One-year survey 9 10 8 • ~800 blazars 10 Non-blazar 7 Fermi 10 • 1~10 non-blazar AGNs Fermi AGN N(>Flux) [(4 π sr) -1 ] N (>Flux) [(4 π sr) -1 ] 6 10 • Five-year survey EGRET 5 10 Blazar • ~1200 blazars EGRET 4 10 • 4~50 non-blazar AGNs 3 10 Blazar: U03(q, γ 1 ) 2 • Nonthermal gamma-ray 10 Non-blazar ( Γ =3.5) flux from NGC 4151, the 1 Non-blazar ( Γ =3.8) 10 Blazar + Non-blazar ( Γ =3.5) brightest Seyfert AGN 0 10 Blazar + Non-blazar ( Γ =3.8) • Flux(>100 MeV): ~1e-8 γ /cm/s -1 10 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 10 10 10 10 10 10 10 10 10 10 10 • Photon Index: ~3.5 -2 s -1 ] Flux(>100MeV) [photons cm -2 s -1 ] Flux (>100MeV) [photons cm 8

Will Fermi resolve the cosmic gamma-ray background? FdN/d(log 10 F) [photons cm -2 s -1 sr -1 ] 10 -5 • Five year survey will Non-blazar Fermi F γ dN/d(log 10 F γ ) [photons cm -2 s -1 sr -1 ] resolve AGN 10 -6 • ~99% of the 10 -7 background flux Fermi from blazars (>100 EGRET EGRET 10 -8 MeV). Blazar • ~0.01% of the 10 -9 background flux Blazar: U03 (q, γ 1 ) Non-blazar ( Γ =3.5) 10 -10 from non-blazar Non-blazar ( Γ =3.8) Blazar + Non-blazar ( Γ =3.5) AGNs (>100 MeV). Blazar + Non-blazar ( Γ =3.8) 10 -11 10 -15 10 -14 10 -13 10 -12 10 -11 10 -10 10 -9 10 -8 10 -7 10 -6 Flux (>100MeV) [photons cm -2 s -1 ] Flux(>100MeV) [photons cm -2 s -1 ] 9

Fermi blazar @ z~7 1000 ~5-years survey F lim (>100MeV)=1 × 10 -9 photons/cm 2 /s • Predictions for z~7 U03( q ) U03( q , � 1 ) blazar detectability 100 U03( q , � 1 ): p 2 =3.5 • based on IT09 YI&TT09 N(>z) YI&TT09 +SDSS • improved at 10 z~7 high-z based on SDSS quasar LF 1 upto z~6. 0.1 0 2 4 6 8 10 12 14 Redshift z z ~1 blazar @ z~7 with ~5-year Fermi survey (YI+in prep.). 10

Probing high-z universe through GeV gamma-ray attenuation • γ (>GeV) + γ UV → e + +e - . 100 z=0.1 z=0.3 z=1.0 z=3.0 GeV flux attenuated z=0.1 z=0.3 z=1.0 z=3.0 by high-z UV 10 background (Oh ’01, 1 1 Gilmore+09, S.Inoue+09) . Optical Depth • information of early 0.1 Optical Depth � 100 star/galaxy formation z=5.0 z=6.0 z=7.0 z=5.0 z=6.0 z=7.0 Semi-analytical may be obtained. model 10 Mitaka model Kneiske+04 Kneiske+04 • Red model: consistent with S.Inoue+09 S.Inoue+09 1 z<5 data (e.g. galaxy LF) 1 • Blue model: consistent 0.1 with z>5 data (e.g. reionization data) 1 10 100 1 10 100 1 10 100 Energy (GeV) (YI+in prep.) 11

Summary 1 • New blazar GLF (Y. Inoue & Totani ’09, arXiv:0810.3580) • Blazar SED sequence incorporated • Non-trivial prediction for the cosmic gamma-ray background • Our prediction matched very well with the Fermi data. • AGNs are the primary sources as the origin of cosmic X- ray/Gamma-ray background. 12

Summary 2 • Fermi will find • ~800 blazars and 1~10 non-blazar AGNs in 1-year survey, • ~1200 blazars and 4~50 non-blazar AGNs in 5-year survey. • Fermi will resolve • ~99% of the gamma-ray background from blazars (>100 MeV), • ~0.01 % of the gamma-ray background from non-blazar AGNs (>100 MeV). • ~1 blazar @ z~7 may be found by Fermi. • A new key to understanding the high-z cosmic evolution. 13