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ALMA Users Workshop 8 February, 2010 S á ndor M. Moln á r, Patrick Koch Institute of Astronomy and Astrophysics, Academia Sinica, Taipei, Taiwan. PART II Simulations of Shocks in Clusters of Galaxies. Collaborators for FLASH Simulations :. Nathan Hearn (Univ. of Chicago)
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ALMA Users Workshop 8 February, 2010 Sándor M. Molnár, Patrick Koch Institute of Astronomy and Astrophysics, Academia Sinica, Taipei, Taiwan PART II Simulations of ShocksinClusters of Galaxies
Collaborators for FLASH Simulations: Nathan Hearn (Univ. of Chicago) Joachim Stadel (Univ. of Zurich)
Outline • I. Shocks in Clusters of Galaxies: Observations • II. Shocks in Clusters of Galaxies: FLASH 3D Simulations • III. Applications to ALMA: work in progress • IV. Summary
Coma Cluster of Galaxies (z=0.025, 2x1015 M⦿); optical image (Kitt Peak National Observatory).
The bullet cluster: 1E0657-56: Mach ~ 3; Markevitch & vikhlinin (2007); Clowe et al. (2006).
Shocks in Clusters of Galaxies • Rankine-Hugoniot jump conditions ρ2 / ρ1 = (γ+1) M12 / ((γ-1) M1 2 +2) P2 / P1 = 1 + 2 γ (M12 -1)/ (γ+1) T2 / T1 = (1+γ (2 M12 -1))(2+(γ-1) M12)/((γ+1)2 M12)M1 = ( 2 r / (γ + 1 – r (γ-1) )-1 Compression: r = ρ2 / ρ1
FLASH Simulations of clusters of galaxies total mass: 1014 M⦿ - 1015 M⦿ • dark matter NFW from Navarro at el. (1997):ρgas ~ ( r/rs )-1 (1 + r/rs)-2 R < Rcut σrfrom Lokas & Gamon (2001) • ICG model • density: β model: ρ ~ (1 + r2/r2core)-3β/2 R < Rcut • temperature: from hydrostatic equilibrium • previous simulations: GADGET2 (SPH): Springel & Farrar (2007); GASOLINE (SPH): Mastropietro & Burkert (2008); FLASH 2D: Milosavljevic et al. (2007) FLASH 3D: ZuHone et al. (2009a, b)
FLASH Simulations of clusters of galaxies • Simulations for high resolution SZ-X-ray observations: RXJ1347
High-resolution multi-wavelength observations of RXJ1347 • (Mason et al. 2010; submitted to ApJ.)
FLASH 3D simu- • lations for RXJ1347 • (Molnar et al. 2010; • in prep.)
Why arc second resolution? • To understand the physics of the cluster gas: • The role of transport proceses Thermal viscosity Conduction • Turbulence • Magnetic fields • Can we model clusters well enough to do precision cosmology? • Example: arc second resolution in X-ray: • Turbulent intra-cluster gas with disturbed struct. • shock physics: below the Coulomb mean free path • Arc sec SZ (ALMA) • Accurate pressure distribution: same as X-ray resol.
Work in progress • Accretion shocks in clusters of galaxies: hard to observe but important (Molnar et al 2009) • Merger shocks in clusters of galaxies: CASA simulations based on images from FLASH 3D simulations
IV. Summary • Arc minute scale: Clusters of galaxies for cosmology • numbers counts • scaling relations (e.g., AMiBA) • Few arc second to (sub)arc second: Cluster physics • 10 arc second: shock features appear (e.g., Mustang) • 1 arc second: detailed maps comparable to X-ray (ALMA)