logging in or signing up LIU MIT 2006 BAWare Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 46 Category: Entertainment License: All Rights Reserved Like it (0) Dislike it (0) Added: November 28, 2007 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Electron Acceleration in Magnetized Accretion Disks: Electron Acceleration in Magnetized Accretion Disks Siming Liu Los Alamos National Laboratory, T-6 Jon Bittner (Yale), Vahé Petrosian (Stanford), Fulvio Melia (U of A), Chris Fryer (LANL) MIT, Oct 20 2006Outline: Outline From MHD Simulations to Observations Energy Flow in Black Hole Accretion Electron Acceleration in Magnetized Accretion Disks Testing the Acceleration ModelFrom MHD Simulations to Observations: From MHD Simulations to Observations MHD Simulation of Accretion Torus in Sgr A*: MHD Simulation of Accretion Torus in Sgr A* Spectral Methods; Pseudo-Newtonian Potential M = 3.4*106 Msun From 1.5 r_S to 20 r_S; Scale height: H = r_S Chan et al. 2006 QPOs: Accretion Rate: QPOs: Accretion Rate Chan et al. 2006QPOs: Light Curve: QPOs: Light Curve Chan et al. 2006Emission Model Parameters: Emission Model Parameters Thermal: Good for thin disk Two Temperature: 1 Plus a power law tail: 4 (Emin, Emax, p, N) Broken power law: 2 Structure of the Accretion Flow: Structure of the Accretion Flow De Villiers et al. 2003 ApJEnergy Flow in Black Hole Accretion: Energy Flow in Black Hole Accretion MRI Gravitational Energy Magnetic Turbulence Internal Energy + Radiation + OutflowCoupling between Electrons and Protons in Magnetized Disks: Coupling between Electrons and Protons in Magnetized Disks Magnetic Fields play important roles in electron heating and cooling. It also provides the stress for accretion. If magnetic field pressure is proportional to the stress, the coupling between electrons and protons can be addresses self-consistently. Slide11: Stochastic Electron Acceleration in Magnetized Accretion DisksStochastic Electron Acceleration: Stochastic Electron Acceleration Liu et al. 2006Evolution of Electron Spectrum: Evolution of Electron Spectrum Bittner et al. 2006Evolution of Synchrotron Spectrum: Evolution of Synchrotron Spectrum Bittner et al. 2006Stochastic Electron Heating: Stochastic Electron Heating Bittner et al. 2006Evolution of Mean Energy: Evolution of Mean Energy Bittner et al. 2006 a=1.6 a=1.0Relative Error of the Model: Relative Error of the Model Bittner et al. 2006Stochastic Electron Heating: Stochastic Electron Heating Bittner et al. 2006Slide19: Testing the Acceleration ModelThermal Synchrotron: Thermal SynchrotronThermal Synchrotron and SSC: Thermal Synchrotron and SSCSlide22: Liu et al. 2006 Steady-State Liu et al. 2006Thermal Synchrotron and SSC: Thermal Synchrotron and SSC Four Parameters B, kBT = γcmec2, N , A≈R2Structure of the Accretion Flow: Structure of the Accretion Flow De Villiers et al. 2003 ApJSub-mm Emission from Sgr A*: Sub-mm Emission from Sgr A*Slide26: Acceleration within 20rSM87: M87 Biretta et al. 1999Flares from Sgr A*: Flares from Sgr A* Liu et al. 2006Conclusion: Conclusion Electron acceleration needs to be addressed to study magnetized accretion disks. In collisionless plasma, magnetic turbulence play roles in electron heating, cooling and driving the accretion. Observations and MHD simulations can test the electron heating model. You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
LIU MIT 2006 BAWare Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 46 Category: Entertainment License: All Rights Reserved Like it (0) Dislike it (0) Added: November 28, 2007 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Electron Acceleration in Magnetized Accretion Disks: Electron Acceleration in Magnetized Accretion Disks Siming Liu Los Alamos National Laboratory, T-6 Jon Bittner (Yale), Vahé Petrosian (Stanford), Fulvio Melia (U of A), Chris Fryer (LANL) MIT, Oct 20 2006Outline: Outline From MHD Simulations to Observations Energy Flow in Black Hole Accretion Electron Acceleration in Magnetized Accretion Disks Testing the Acceleration ModelFrom MHD Simulations to Observations: From MHD Simulations to Observations MHD Simulation of Accretion Torus in Sgr A*: MHD Simulation of Accretion Torus in Sgr A* Spectral Methods; Pseudo-Newtonian Potential M = 3.4*106 Msun From 1.5 r_S to 20 r_S; Scale height: H = r_S Chan et al. 2006 QPOs: Accretion Rate: QPOs: Accretion Rate Chan et al. 2006QPOs: Light Curve: QPOs: Light Curve Chan et al. 2006Emission Model Parameters: Emission Model Parameters Thermal: Good for thin disk Two Temperature: 1 Plus a power law tail: 4 (Emin, Emax, p, N) Broken power law: 2 Structure of the Accretion Flow: Structure of the Accretion Flow De Villiers et al. 2003 ApJEnergy Flow in Black Hole Accretion: Energy Flow in Black Hole Accretion MRI Gravitational Energy Magnetic Turbulence Internal Energy + Radiation + OutflowCoupling between Electrons and Protons in Magnetized Disks: Coupling between Electrons and Protons in Magnetized Disks Magnetic Fields play important roles in electron heating and cooling. It also provides the stress for accretion. If magnetic field pressure is proportional to the stress, the coupling between electrons and protons can be addresses self-consistently. Slide11: Stochastic Electron Acceleration in Magnetized Accretion DisksStochastic Electron Acceleration: Stochastic Electron Acceleration Liu et al. 2006Evolution of Electron Spectrum: Evolution of Electron Spectrum Bittner et al. 2006Evolution of Synchrotron Spectrum: Evolution of Synchrotron Spectrum Bittner et al. 2006Stochastic Electron Heating: Stochastic Electron Heating Bittner et al. 2006Evolution of Mean Energy: Evolution of Mean Energy Bittner et al. 2006 a=1.6 a=1.0Relative Error of the Model: Relative Error of the Model Bittner et al. 2006Stochastic Electron Heating: Stochastic Electron Heating Bittner et al. 2006Slide19: Testing the Acceleration ModelThermal Synchrotron: Thermal SynchrotronThermal Synchrotron and SSC: Thermal Synchrotron and SSCSlide22: Liu et al. 2006 Steady-State Liu et al. 2006Thermal Synchrotron and SSC: Thermal Synchrotron and SSC Four Parameters B, kBT = γcmec2, N , A≈R2Structure of the Accretion Flow: Structure of the Accretion Flow De Villiers et al. 2003 ApJSub-mm Emission from Sgr A*: Sub-mm Emission from Sgr A*Slide26: Acceleration within 20rSM87: M87 Biretta et al. 1999Flares from Sgr A*: Flares from Sgr A* Liu et al. 2006Conclusion: Conclusion Electron acceleration needs to be addressed to study magnetized accretion disks. In collisionless plasma, magnetic turbulence play roles in electron heating, cooling and driving the accretion. Observations and MHD simulations can test the electron heating model.