A Search for Blazars among the Unidentified EGRET Gamma-Ray Sources. P.J. Meintjes & P. Nkundubakura

Outline CGRO and Fermi AGN Candidates: Selection Criteria Observations and Modelling Conclusions

Compton Gamma-Ray Observatory: EGRET 1/23/2018

EGRET Sky Map

EGRET The EGRET legacy Total: 271 sources ~100 AGNs All radio loud ~97 % blazars ~75% FSRQs and 25 % BL Lac (90% LBL) ~140 still unidentified.

EGRET Sources 140 unidentified

Identified EGRET Sources

The Large Area Telescope (LAT) on board Fermi has better capability than EGRET

Multiwavelength observations A one-Year scan of Fermi- LAT (@ 20 MeV<E<300 GeV) Galactic plane Geminga pulsar Crab pulsar Vela 3C345.3

A one-Year scan of Fermi- LAT (@ 20 MeV<E<300 GeV) 1049 sources Galactic plane Geminga pulsar Vela Crab pulsar 3C345.3

Fermi first 11 months Data of 11 months: Total: 709 AGNs 663 AGNs with high confidence (86% blazars) 281 FSRQs 291 BL Lacs Others are: 10 radio galaxies 50 unkown Galactic plane Geminga pulsar Vela Crab pulsar 3C345.3 The AGN catalog with Fermi-LAT. 709 AGNs in |b|>10 deg

1/23/2018

Energy extraction from rotating black holes Spinning event horizon acts like a surface with resistance of 377 Ohm 1/23/2018

Energy Extraction from Rotating Black Holes For Cygnus A: B ~ 104 G; M ~ 109 MO Emf ~ W F ~1020 V Rin ~ Rout ~ 100 W I ~ V / R ~ 1018 A P ~ Emf x I ~ 1038 W Blandford - Znajek Model 1/23/2018

Particles are accelerated within the jets possibly in shocks between different clumps of plasma moving at different speeds

Contribution of the Accretion disk and the Broad Line Region to the Luminosity

Properties of blazars BL Lacs subclasses Mrk 421 (HSP- BL lac) BL Lacertae (LSP-BL Lac) sync <1014 Hz sync >1016 Hz 17

Cosmic Particle Accelerators Origin of cosmic ray protons? Galactic SNRs (Supernova Remnants) are considered as the best candidates for cosmic-rays below “Knee”. CR energy sum consistent with SNR kinetic energy. Cosmic-rays above “Knee” are considered extragalactic. Gamma-ray bursts (GRB). Active Galactic Nuclei. Galaxy clusters. 1/23/2018 eV

Unified models of AGNs suggest that different types of AGNs are really defined by how we see them. Blazars are observed when jets are pointed towards Earth

Blazars are viewed close to the jet axis. Radiation is highly boosted 22

Selection Criteria Inside error box of detection Extragalactic (b>10 deg) Confirmed as extra-galactic in NASA/IPAC Extra-Galactic Data Base (NED) Radio Bright (F > 100 mJy at 8.4GHz) Variability Hard Radio spectrum between 1.4 - 8.4 GHz

Radio Source in Error Box

Candidates

Galactic Distribution

MW-Data

EGRET-FERMI Gamma-Ray Spectra

EGRET-FERMI Gamma-Ray Spectra

EGRET-FERMI Gamma-Ray Spectra

EGRET-FERMI Gamma-Ray Spectra

Spectral Index Distribution

Multiwavelength observations Femi-LAT detected sources

3EG J 0706-3837 and 3EG J 0821-5814

Multi-Wavelength Follow-Up Sutherland SALT HartRao CTIO

Optical Spectroscopy using the Goodman spectrograph at the SOAR Observatory (Chile)

Identification

3EG J0821-5814

3EG J0706-3837

Optical spectra of blazars Properties of blazars Optical spectra of blazars BL Lac RBS 1752 Spectrum of a featureless non-thermal emission FSRQ 1RXS J072418.3-071508 40

Dressler and Shectman, 1987 K4000 < 40% Jet -- Blazar K4000 > 40% Weaker non-thermal emission

K4000-Depression

X-Ray Luminosities

Hartebeesthoek Radio Astronomical Observatory Ta

Radio Spectra

SALT

SAAOP 1.9 m

SAAO 1.0 m

Optical Variability: 3EG J0821

Optical Variability: 3EG J-0706

Estimation of BH Mass

EC SSC

Seyfert 1: z = 0.12 MRK 501 : z = 0.03 HBL : z=0.06

Summary

Models: SSC + EC

Models: SSC+EC

The Robert Stobie Spectrograph (RSS) Science Phase in 2011-2012 Longslit, multi-object, Fabry-Perot spectroscopy, polarimetric capabilities Optical wavelength range: 320nm – 900 nm; with planned NIR: up to 1600 nm Volume phase holographic gratings ~90% effective

1/23/2018