Astroparticle yield in radio galaxies jets and hot spots

1. Astroparticle yield in radio galaxies jets and hot spots A.Marcowith (C.E.S.R. Toulouse France) F.Casse (F.O.M. Rijnhuizen, the Netherlands & A.P.C. Paris, France)

2. Outline • Multi- & high spatial resolution observations. • Methodology: MHD-SDE code. • Jets & hot spots: - Particle transport in complex flows - Microscopic turbulence - Astroparticle yield • Future works.

3. Multi- observations • Multi-wavelength spectra • High resolution maps (VLBI, HST, Chandra & XMM-Newton).  Spectral and spatial analysis • Supernova remnants (van der Swaluw & Achterberg 2004) • Massive star formation sites (poster on Super-bubbles) • Active Galactic Nuclei jets and hot spots (this talk)

4. Radio-X-ray jets IC/CMB ? synchrotron Sambruna et al. 2002 1’’ = 5.4 kpc

5. FRII hot spots Hot spot A Wilson et al. 2000 core jets Chandra Cygnus A (VLA 5 GHz ) SSC FR = Fanaroff Riley radio-galaxies FRII are the most powerful RG.

6. Astrophysical interests • Radiative processes in high energy sources: - Origin of the X-ray radiation in jets and hot spots • Relativistic particle production, acceleration and propagation: - Cosmic-ray physics. • Constraints on transport processes: - Turbulence (fluid & microscopic), magnetic field configuration, link to macroscopic structures. Need for multi-scale computational methods linking large MHD scale to kinetic transport ...

7. Multi-scale simulation • (3D+time) MHD + kinetic Eq. + radiative processes. • MHD:Versatile Advection Code(www.physics.uu.nl/~toth) - 3D conservative schemes & non-relativistic flows • Kinetic equations: Diffusive approximation - Stochastic differential equations Diffusion-convection equation • Radiative processes:synchrotron/IC losses (e-), hadronic interaction (p-p, p- gamma-ray & neutrino)

8. Diffusive shock acceleration • Constraints on tsde and  Xadv downstream upstream Xdiff Xshock « ideal » sharp discontinuity Numerical smoothing over few grid cells Necessary condition to compute the shock process correctly: Xadv (= Vflow tsde)< Xshock < Xdiff (= √2  tsde) (Kruells & Achterberg 1994 + N Dim. extension Casse & Marcowith 2003)  tsde and min

9. SDEs • 3D axisymetric MHD  Vflow, B, tMHD. • Microscopic turbulence model  diffusion coefficients . • Sum number of particles N(p,t) in a given (r,z)  distribution function at tMHD.

10. Extragalactic jets & hot spots FRI jets: (Casse & Marcowith A&A 2003) • Complex shock structures. • Multiple-shock acceleration. Hot spots:(Casse & Marcowith PRD 2004 sub.) • Constraints on turbulence regime. • Magnetic field configuration. • Astroparticle yield (gamma-rays, high energy neutrinos, cosmic-rays).

11. Complex shock structure Kelvin-Helmoltz instability  internal shocks in jet T1 (weak curved shock: < r > = 2.76) < T2 (strong planar shock: < r > = 4) Stationary sol. F(p)  p-3r/(r-1)

12. Hot spot simulation Poloidal MF AMR-VAC (Keppens 2004)

13. Astroparticle yield in HS Cygnus A: Electrons Cygnus A: protons At the terminal shock Over the HS synchrotron zoom Proton Escaping the HS At the terminal shock Kolmogorov turbulence + poloidal MF Ecr max fixed by escape losses  transport Ecrmax ~ 5 x 1016 eV

14. 3C273A: electrons 3C273A: protons At the terminal shock Over the whole HS At the terminal shock synchrotron zoom Escaping protons Kolmogorov turbulence + toroidal MF Ecrmax ~ 7 x 1019 eV

15. E-2 spectrum Secondaries from 3C273A • Neutrinos flux on Earth: 2.3 x 10-14 GeV / cm2 s sr (~ 5 orders of magnitude under ANTARES sensitivity) • p-p gamma-ray flux on Earth: 4.7 x 10-14 GeV / cm2 s sr (~ 3 orders of magnitude under GLAST sensitivity)

16. Conclusions • Methodology: • Multi- high resolution observations  multi-scale simulations to handle > Macroscopic structures. > Microscopic physics. • Mesoscopic simulation schemes MHD-EDS + Easy to implement, able to handle complex flows configurations with shocks. - Statistics, test-particle approximation. Other methods do exist (T. Downes et al. 2002, T. Jones et al. 1999, A. Micono et al. 1999)

17. Astrophysics: Jets & Hot spots • Investigate complex shock structure in jets and hot spots • Constraints on acceleration mechanisms or turbulence • Multi- spectra + astroparticle • 3C273A (transverse shock acceleration + high synchrotron cut-off ~ 1014 Hz)

18. Future works • Full time-dependent simulation for FRI jets • X-ray dominated synchrotron: astroparticle production (FRI & some hot spots) • Multi-wavelength maps • Other objects (SNr,SNr-cloud interaction, colliding stellar winds...) • Extension to relativistic flows (FRII radio-galaxies) • Make time dependent SDEs available for the community and insert an SDE routine in VAC and AMR-VAC.

19. Multiple shock effects Test particle approximation theory: p F(p)  p-(tacc/tesc) Multiple shock with no escape  flat p F(p) distribution + Synchrotron losses • Spectral energy distribution without synchrotron losses for • Const. Diff. Coeff. • Kolmogorov with ≠ turbulence level

20. MHD turbulence in HS • Test // and  shocks (poloidal or toroidal MF dominated HS) • Test different transport theory • Isotropic: Kolmogorov, Kraichnan, Bohm. • Anisotropic: Goldreich-Sridhar • Main conclusions • Highest CR energies for Kolmogorov with toroidal MF. • HS with high synchrotron cut-off (optical ~1014 Hz) are prone to be efficient astroparticle (secondaries from p-p and p- interaction: Ep (E/1eV)> 6.6 1016 eV) sources. • Best candidate in Meisenheimer et al. 1989 & 1997 list: • 3C273A(low radio power, high synchrotron cut-off, CR accelerator Ecrmax ~ 7 x 1019 eV). • Cygnus A (powerful radio source, low synchrotron cut-off ~1012 Hz, not expected to be a strong astroparticle source.

21. Astrophysics: Jets & Hot spots • Hard spectra produced by multiple shocks acceleration (alternative radiative model) • Oblique-perpendicular shocks with Kolmogorov type turbulence favored to produce high energy CRs • Weaker radio but optical Hot spots are expected to be astroparticle sources • - Good candidate 3C273A (transverse shock acceleration + high synchrotron cut-off ~ 1014 Hz)