AAS SD05 present

TeV Emission from the Galactic Center Black-Hole Plerion: 

TeV Emission from the Galactic Center Black-Hole Plerion Chuck Dermer (NRL) & Armen Atoyan (Université de Montréal) dermer@gamma.nrl.navy.mil ApJ Letters (2004) AAS, San Diego January 10, 2005 Upper limit to source size <3' < 7 pc  < 107 rg Aharonian et al 2004

Multiwavelength Observations of Sgr A*: 

Multiwavelength Observations of Sgr A* ~1036 ergs s-1 2 cm VLA radio of Sgr A West Sgr A* Aharonian and Neronov 2004 (Yusef-Zadeh & Wandle 1993)

Multiwavelength Observations of Sgr A*: 

~1036 ergs s-1 Multiwavelength Observations of Sgr A* Chandra Obs. of Sgr A* Sgr A* Baganoff et al. 2003

Multiwavelength Observations of Sgr A*: 

~1036 ergs s-1 Multiwavelength Observations of Sgr A* Baganoff et al. 2001

Multiwavelength Observations of Sgr A*: 

~1036 ergs s-1 Multiwavelength Observations of Sgr A* EGRET emission displaced from direction to GCBH EGRET Obs of Galactic Center Dingus and Hooper 2002; Pohl 2005

TeV Radiation from the Galactic Center Black-Hole Plerion: 

F2 F1 Termination shock F1 m . ADAF m . TeV Radiation from the Galactic Center Black-Hole Plerion

Accretion Physics in the ADAF/ADIOS Regime: 

Esin, McClintock, & Narayan (1997) Accretion Physics in the ADAF/ADIOS Regime Advection-dominated accretion flow (ADAF) model for compact objects accreting at low Eddington accretion rate Radiant luminosity at the level is fraction of accretion power that is advected into black hole or convectively escapes 10-8 The ADAF ~20 rg

Second-order Fermi Acceleration in the ADAF: 

Dermer, Miller & Li 1996; Liu, Petrosian, & Melia 2004 Second-order Fermi Acceleration in the ADAF No optically thick accretion disk Second-order stochastic Fermi acceleration for radio-sub mm emission for a region of size 20 rS Equating acceleration rate of electrons by Whistler turbulence to synchrotron loss rate: Steady-state electron spectrum:

Stochastic acceleration model for radio/sub-mm emission: 

Stochastic acceleration model for radio/sub-mm emission Atoyan & Dermer (2004)

The Black Hole Plerion: 

The Black Hole Plerion Particle escape by convective outflow in advection-dominated inflow-outflow source (ADIOS) extension (Blandford & Begelman 1999) of ADAF model. Assume a wind power With speed vwindc/2 directed into solid angle W  1 sr Wind terminates at a subrelativistic shock at found by equating thermal gas pressure with energy density of wind Electrons and protons accelerated by first-order (shock) Fermi acceleration. Electrons emit X-ray synchrotron radiation to form quiescent X-ray emission and Compton scatter ADAF emission 1013 Hz emission from cold dust ring around Sgr A* Neutron Star Plerion: Crab Nebula

Radio/sub-mm, quiescent X-ray, TeV emission: 

Atoyan & Dermer (2004) Radio/sub-mm, quiescent X-ray, TeV emission

Flaring Emissions from Inner Region: 

Flaring Emissions from Inner Region Flares from instabilities in accretion flow that form shocks at few rS First-order Fermi shock acceleration injects electrons with g < 106, -2.2 injection index Explains X-ray/NIR flares and short variability timescales from cooling and expansion Self-absorbed flares at < 100 GHz from same electrons in “expanding source” scenario 200 s 1200 s 3600 s ff at 200 s ne = 108 cm-3

Galactic Center Black Hole Emission:Sgr A* ADAF + Black-Hole Plerion + Sgr A West, a black-hole remnant: 

Galactic Center Black Hole Emission: Sgr A* ADAF + Black-Hole Plerion + Sgr A West, a black-hole remnant Predict GLAST detection of quasi-stationary Compton and bremsstrahlung fluxes from pc-scale plerion. Propagation of GeV electrons power Sgr A West EGRET emission from young pulsar Atoyan & Dermer (2004)

Summary : 

Observations imply two emission regions: Inner ADAF region near black hole Black hole plerion at the termination shock of wind/convective outflow of ADAF X-ray flares are synchrotron emission within ~10 rS of GCBH TeV g rays made by black-hole plerion, first of a new class of nonthermal emitters Black-hole plerionic emission from BL Lac objects and binary compact objects: mid-latitude unidentified EGRET sources? Quasi-stationary TeV emission (southern hemisphere Crab): TeV calibration source Summary Sgr A* Sgr A West Sgr A East 6 cm VLA radio of Sgr A East and Sgr A West (Yusef-Zadeh, Melia, & Wandle 2000)