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A. MacFadyen & W. Zhang (NYU), Alexandria (Magneto-) Hydrodynamics of GRB Outflows 2D Afterglow Jet Relativistic MHD Turbulence arXiv:0902.2396 arXiv:0811.3638
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A. MacFadyenBanff URJA 7/14/05 GRB photons are made far away from engine. Can’t observe engine directly with light. (neutrinos, gravitational waves?) Electromagnetic process or neutrino annihilation to tap power of central compact object. Hyper-accreting black hole or high field neutron star (rotating)
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Relativistic Blastwave 10^52 erg eta = E/m > 100 R = 1 = 3x10^10cm n = 1 cm^-3 Blandford & McKee (1976) Г >> 1 Self similarity
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Fireball Acceleration pressureГ-1 Log R AM & Zhang, Kobayashi, Piran & Sari (1999)
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Required Resolution ~ 1/Г 2
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Transition to Non-relativistic -3 -3/2 E = 10^52 erg n = 1 cm^-3 Log ( Г -1) Log R
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Erice, J. Wheeler SchoolAndrew MacFadyen (NYU) Please see talks by: Bucciantini, McKinney & Nagataki AMR Collapsar Jet + Ni-56 rich Wind Magnetic Tower
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Deceleration Relativistic E ~ Г 2 ρ R 3 Г ~ R -3/2 Jet “spreading” Г ~ 1/θ jet Newtonian E ~ v 2 ρ R 3 v 2 ~ Г-1 ~ R -3
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Erice, J. Wheeler SchoolAndrew MacFadyen (NYU) Collapsar vs. Magnetar Uzdensky & AM (2007,2008)
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Erice, J. Wheeler SchoolAndrew MacFadyen (NYU) Uzdensky & AM (2006,2007), Kommisarov et al (2007), Bucciantini et al (2007), Dessart et al (2007) Magnetic Tower
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Relativistic GRB Jet (AMR)
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Erice, J. Wheeler SchoolAndrew MacFadyen (NYU) Adaptive Mesh Refinement (AMR) - Emery Step Test
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Shear Flow Resolution 400 3200 51200
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Smooth & Spherical
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Clumpy & Spherical
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Erice, J. Wheeler SchoolAndrew MacFadyen (NYU) Vorticity Generation A ≡ (ρ 1 -ρ 2 )/(ρ 1 +ρ 2 ) ρ1ρ1 ρ2ρ2 ∇P∇P ∇ρ∇ρ η t = k[u]Aη Ultra-relativistic Vorticity and Shock Dynamics Goodman & MacFadyen (2008)
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Clumpy Medium
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Jet & Shear
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Jet & Clumps
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Flying Pancakes
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Misaligned
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Oblique
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Colliding Clumps
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Shear Patches Kelvin-Helmholtz Instability
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Kelvin Helmholtz Clouds Beverly Shannon
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Big Whirls Have Little Whirls Joly et al (2008)
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2D Relativistic HD KH
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Twisting and Folding
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KH:1024^3 Rel. MHD
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Mag. & Kin. Energy
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Power Spectra
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AG Jet Initial Conditions Blandford-McKee E iso = 1e52 erg n o = 1cm -3 Г = 23.1 Θ jet = 0.2, 0.4 Spherical R o = 1.59e17 cm R/ΔR = 196608 4e10 zone equiv. R θ Г = 23.1 Text
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2D GRB Blastwave
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2D Blastwave (energy)
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Energy Spreading
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Light Curves Zhang & MacFadyen (2009)
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Light Surface
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Volume
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A. MacFadyenJAS McGill 9/8/05 TM EOS e=0.5((9θ 2 +4) 0.5 +3θ-2) θ≡P/ρUltrarelativistic Г=4/3 Newtonian Г=5/3 e= θ/(Г-1)
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Conclusions (Mild) RMHD Turbulence has Kolmogorov-like spectrum GRB AG Jets take > 10 years to isotropize
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Newton vs. Relativistic Hydro Conservation of mass momentum, energy j momentum coupled to i through Lorentz Factor Relativistic when W>1 AND/OR
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A. MacFadyenIPAM UCLA 5/3/05 Method WENO 5 th order (Jiang & Shu,1996) SRHD characteristic stucture (Donat et al 1998) Runge-Kutta 3 rd order (Shu & Osher 1988) Also PLM reconstruction w/ minmod (Kurganov & Tadmor, 2000) F-WENO, F-PLM, U-PPM, U-PLM AMR from PARAMESH/FLASH2.3
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Erice, J. Wheeler SchoolAndrew MacFadyen (NYU) 5 th order accuracy Method N L1 Error Convergence Rate
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Alpha
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CR acceleration (prelim) Zrake et al (2009)
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CR acceleration (prelim) Zrake et al (2009)
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A. MacFadyenNYU 1/27/06 Collapsar – Relativistic AMR (2005) rho ~ 10^9 g/cm^3 T ~ 10^10 K M_dot ~ 0.1 M_sun/s t_acc ~ 20 s R_in ~ 2 R_g AM, Zhang, Woosley (2005)
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Alpha Zhang & MacFadyen (2009)
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Blast Evolution Zhang & MacFadyen (2009)
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Spectra Zhang & MacFadyen (2009)
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2D Blastwave (density) Zhang & MacFadyen (2009)
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