1. Interaction of Hydra A Jets with the Intracluster Medium Mohammad Ali Nawaz Prof. Geoffrey Bicknell RSAA, ANU Prof. Geoffrey Bicknell RSAA, ANU Dr. Alexander Wagner Tsukuba University, Japan Dr. Ralph Sutherland RSAA, ANU Prof. Brian McNamara Waterloo University, Canada Dr. Alexander Wagner Tsukuba University, Japan Dr. Ralph Sutherland RSAA, ANU Prof. Brian McNamara Waterloo University, Canada

2. log I ν (mJy/arcsec 2 ) Hydra A: Radio morphology Bright Knots Turbulent transition ‣ Four bright knots Reconfinement shocks? ‣ Curved jet Jet Precession? ‣ Turbulent transition hydra A 5 GHz 100 kpc 20 kpc 10 kpc Lobe

3. Reconfinement shocks Astrophysical jet knots are Reconfinement shocks Norman et al., 1982 Oscillation of the jet boundary: Prandtl, 1907 Reconfinement Shocks Turbulent transition Jet boundary oscillation Laboratory jet Simulated jet Reconfinement shocks in laboratory jets: Mach, 1890

4. Model setup

5. Pressure Lorentz factor Velocity Power Jet inlet radius Density parameter Internal energy density Jet parameters Intracluster medium Atmosphere model based on the X-ray data presented in David et al. 2001

6. Axisymmetric Model Electron-positron jet: γ 1 ~1 Electron-proton jet: γ 1 ~700 Jet composition Λ / r = 2.6 √( M 2 - 1 ) Jet velocity from knot location Natural wavelength of non-relativistic supersonic flow Inlet radius Flow Mach number (Birkhoff & Zaranantonello 1957) Best fit values β jet = 0.8 χ jet = 13

7. Precessing Jet: Curvature 10 P = 1 Myr P = 5 Myr P = 10 Myr P = 15 Myr P = 25 Myr ψ = 20 o ψ = 15 o ψ = 20 o Best fit model Best fit parameters Precession period, P = 1 Myr Precession angle, ψ = 20 o

8. log I ν (arbitrary scale) Evolution of synthetic radio source Jet parameters: P jet = 10 45 ergs/s β jet = 0.8 p jet /p a = 5 χ jet = 13 ICM: Modelled from the X-ray data of David et al. 2001 Grid resolution: 456 x 456 x 456 11 cells across the jet

9. Precessing Jet: Radio morphology Hydra A northern jet Simulated jet

10. Heating of the atmosphere M = 1.85 McNamara et al. 2012 -> Gentle heating

11. Jet precession period: Theoretical Time scale Outer disk angular momentum Black-hole spin-axis Outer disk inner disk black hole Precession time-scale black hole spin parameter Accretion disk paramater Disk height at radius r Efficiency parameter Black hole mass

12. Summary 1. Bright knots are Reconfinement shocks. 2. Jet Velocity from the spacing of the bright knots and oscillation in the jet radius: β = 0.8c (First time used in extragalactic jets) 3. Complex radio morphology: Jet Precession~1Myr period and 20 o precession angle. 4. Gentle Heating of the ICM 5. Theoretical precession time-scale of Hydra A jets: 1Myr

13. Thank You