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Yaël Fuchs Service d’Astrophysique, CEA/Saclay (France) PowerPoint Presentation
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Yaël Fuchs Service d’Astrophysique, CEA/Saclay (France)

Yaël Fuchs Service d’Astrophysique, CEA/Saclay (France)

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Yaël Fuchs Service d’Astrophysique, CEA/Saclay (France)

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  1. MICROQUASARS JETS:FROM BINARY SYSTEMS TO THE INTERSTELLAR MEDIUM (Multi- observations of MICROQUASARS and high energy neutrinos prospects) Yaël Fuchs Service d’Astrophysique, CEA/Saclay (France)

  2. PLAN • Introduction to microquasars • The X-ray binary systems • Different binary systems • Variability: light curves, changes in states • The different types of jets • Compacts jets • Isolated and superluminal ejections • Large scale jets: interaction with the surrounding medium ex: SS433/W50 and XTE J1550-564 • Comparison to extragalactic jets • Microblazars: candidates • Microquasars: sources of TeV Neutrinos ? • Conclusion

  3. I. Introduction to Microquasars

  4. QUASARS  MICROQUASARS Quasar 3C 223 Microquasar 1E1740.7-2942 VLA at 1477MHz ~ 20 cm radio (VLA) observations at 6 cm Mirabel et al. 1992

  5. MICROQUASARS : ARTIST’S VIEW

  6. MICROQUASAR / QUASAR / GRB ANALOGY

  7. Wind • Visible  radio • (free-free) • M • EMISSIONS FROM A MICROQUASAR • Compacts jets • Radio  IR •  X? • (synchrotron) • Donor star • IR  UV • (thermal) • Disc • + corona ? • X  IR • therm + non therm • Large scaleejection • Radio & X • Interaction with environment • Dust ? • IR  mm • (thermal)

  8. II. The X-raybinary systems

  9. type of the donor star  type of accretion (wind or Roche lobe overflow) • very different scales: DIFFERENT BINARY SYSTEMS J.A. Orosz Every X-ray binary is a possible microquasar!

  10. VARIABILITY GX339-4 lightcurve • Variations = changes in the stateof the source • lightcurves: • GX 339-4 / GRS 1915+105 •  Variations on very different time scales ! •  “easy” observations for human time scale 1996 2003 GRS 1915+105 X (2-10 keV) Radio (2,25 GHz) Rau et al (2003)

  11. VARIABILITY : state changes “Classically” : soft X-rays  disc (thermal), hard X-rays  corona (IC of therm. phot.) Some state changes  transient ejections, ex: off  high/soft Radio & X-ray spectrum Accretion disc Radio jet • compact jets radio – hard X-ray correlation Fender (2001)  states // radio quiet / loud AGNs?

  12. accretion / ejection coupling Mirabel et al (1998) Marscher et al (2002) • cycles of 30 minutes in GRS 1915+105 : • ejections after an X-ray dip • disappearance / refilling of the internal part of the disc ? • transient ejections during changes of states • same phenomenum in the quasar 3C 120 ?  far slower !

  13. III. The different types of jets

  14. COMPACTS JETS Observations : imagein radio (difficult: mas. !) orspectrum: radio flat (easier) Dhawan et al. (2000) Fuchs et al. (2003) flat spectrum GRS 1915+105 GRS 1915+105 flat or inverted spectrum model: conical jet cut 1/Rmin shock accelerated e- • optically thick synchrotron emission from radio  IR • optically thin synchrotron in X-rays ? Falcke et al. (2002)

  15. same Lorentz factor as in Quasars :  ~ 5-10 SUPERLUMINAL EJECTIONS VLBI at 22 GHz ~ 1.3 cm VLA at 3.5 cm ~ arcsec. scale ~ milliarcsec. scale Mirabel & Rodriguez (1994) • Move on the sky plane ~103 times faster • Jets are two-sided (allow to solve equations  max. distance)

  16. JETS AT LARGE SCALES • Steady jets in radio at arcminute scale • Sources found to be nearly always in the low/hard state •  long-term actionof steady jets on the interstellar medium 1E1740.7-2942 GRS 1758-258 VLA at 6 cm

  17. Vermeulen et al. (1993) JETS ATLARGE SCALES ex: SS 433 / W50 • SS 433 :variablesource in radio & X-rays • distance ~ 3.5 kpc ? • “moving” lines: enormous Doppler-shifts and period of ~162 days • relativistic jets (0.26c) with precession movement •  the 1st microquasar ! (1979) •  acceleration of ions !

  18. W50 Radio + X-ray 2° ~120 pc W50 • relativistic ejections at arcsec.-scale • associated to thermal X-ray emission • (Migliari et al. 2002) • the radio nebula W50 : SN remnant • elongated shape (2°x1°~120pc x 60pc) • due to jets ? • Large scale X-ray jets but no motion observed • East part: non-thermal X-ray emission maybe due to jet / ISM interaction SS 433 • W50 : > 104years • PJ ~ 1039 erg/s • Ec ~ 1051 erg Dubner et al. (1998)

  19. LARGE SCALE JETS ex: XTE J1550-564 • 20 Sept. 1998: strong and brief X-ray flare • Mbh= 10.5 +/- 1.0 M ; d ~ 5 kpc (Orosz et al. 2002) RXTE/ASM lightcurve(1998-99) VLBI 2 –10 keV 20 Sept. 1998 one day X-ray flare Hannikainen et al (2001) Superluminal relativistic ejection (Hannikainen et al. 2001)

  20. Discovery of X-ray sources associated with the radio lobes • Moving eastern source • Alignment + proper motion 23 arcsec  Related to the brief flare of Sept. 1998 First detection of moving relativistic X-ray jets ! • evidence for gradual deceleration • radio-X-ray spectrum: compatible with synchrotron emission from the same e- distribution • external shocks with denser medium?  Particle acceleration, to TeV ? Corbel et al. (2002) XTE J1550-564 : LARGE SCALE X-RAY JETS! Chandra images 0.3 - 8 keV

  21. SUMMARY ABOUT MICROQUASAR JETS • compact jets  milli-arcsecond • isolated ejections caused by state changes in the source • sometimes: superluminal ejections  0.1 to 1 arcsecond • large scale jets: interaction with the interstellar medium  arcminute • composition ? • e-/e+, p+, ions ?

  22. Comparison with extragalactic jets Microquasars :  ~ 1.04 – 30 LJ ~ 1038 – 1040 erg.s-1 Ld ~ 1036 – 1039 erg.s-1 Quasars :  ~ 2.5 – 30 LJ ~ 1043 – 1048 erg.s-1 Ld ~ 1042 – 1047 erg.s-1 3C273:quasar (z=0.158) Pictor A:radio galaxy FR II radio Optical (HST) X-ray Chandra image + radio (20 cm) contours Wilson et al. (2001) XTE J1550-564 Marshall et al. (2001) SS433/W50

  23. thermal(disk) Synchrotron(jet) inverse Compton(jet) Spectrum of a Quasar Jets are the only truly broad-band sources in the universe (radio-TeV)! Lichti et al. (1994)

  24. thermal(disc) • MeV emission due to Synch. Self-Compton from the compact jet? • GeV ? (GLAST) • shocks with the ISMTeV ? Synchrotron(jet) Synchrotron(jet) ? Spectrum of a Microquasar If jet emission extends up to the visible band, the jet has > 10% of the total power Markoff et al. (2001) If jet emissiondominatesthe X-ray band, the jet has > 90% of the total power

  25. MICROBLAZARS • Microblazars = sources with viewing angle < 10°: - time scales lowered by 22 - flux density increased by 83  intense et rapid variations CANDIDATES: • ULXs ? ex: first radio counterpart of an ULX in the NGC 5408 galaxy • galactic sources?  Cyg X-1: gamma-ray flares observed in this region in 2002  V4641 Sgr: rapid optical flares  highmass X-ray binaries + jet sources  interaction of jet with UV photon field from the donor star  inverse Compton • EGRET unidentified sources ? (LS 5039)

  26. IV. Microquasars: sources of TeV Neutrinos ?

  27. Radio Cores: particle accelerators andhigh energy laboratories • Blazarsemit: • 511 keV annihilation line • Gamma-rays • TeV emission • TeV neutrinos •  microblazars ?

  28. Neutrino production mechanism in Microquasars see Levinson & Waxman, Phys. Rev. Letter, 2001 • Hyp: e- / p+ jet • p+ accelerated in the jet to ~ 1016 eV (max En.) • Interaction with: • Synchrotron photons emitted by shock-accelerated e- if E(p+) > 1013 eV • External X-ray photons from the accretion disc if E(p+) > 1014 eV • photomeson production  pions with ~20% of E(p+)  charged pions decay: +  + +   e+ + e +  +   neutrinos with ~5% of E(p+)  Expected to lead to several hours outburst of 1-100 TeV neutrino emission  Should precede the radio flares associated with major ejection events  Detection of neutrinos = diagnostic of hadronic jets _

  29. Neutrino flux predictions for Microquasars see Distefano et al., ApJ, 2002 • Predicted number of muon events in a km2 detector (for E > 1 TeV): background  employing jet parameters inferred from radio observations of various ejection event ! Large uncertainties ! ! Jet power overestimated by a factor of ~ 10-100  detection + microblazars: should emit neutrinos with larger flux  a way of identification

  30. CONCLUSIONS • Advantages of microquasars inspite of their weakness: • Scales of length and time are proportional to the mass of the black hole • shorter phenomena (accretion / ejection link) thus easy to observe for human time scale • internal accretion discemits in the X-rays  good propagation in the interstellar medium • Bipolar jets  maximum distance PROSPECTS • observation of lines  composition of the jets ! • observation ofmicroblazars ! • gamma-rays observation: TeV? jets/ISMinteraction? • TeV neutrino detection • Astrophysics Particle Physics