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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)
PLAN
I. Introduction to microquasars
II. The X-ray binary systems
1. Different binary systems
2. Variability: light curves, changes in states
III. The different types of jets1. Compacts jets
2. Isolated and superluminal ejections
3. Large scale jets: interaction with the surrounding mediumex: SS433/W50 and XTE J1550-564
4. Comparison to extragalactic jets5. Microblazars: candidates
IV. Microquasars: sources of TeV Neutrinos ?
V. Conclusion
I. Introduction to Microquasars
QUASARS MICROQUASARS
Mirabel et al. 1992
Quasar 3C 223 Microquasar 1E1740.7-2942
radio (VLA) observations at 6 cm
VLA at 1477MHz ~ 20 cm
MICROQUASARS : ARTIST’S VIEW
MICROQUASAR / QUASAR / GRB ANALOGY
EMISSIONS FROM A MICROQUASAR
• Donor star IR UV
(thermal)
• Dust ?IR mm(thermal)
• Large scale ejection
Radio & XInteraction with
environment
• Disc + corona ?
X IRtherm + non
therm
• Compacts jetsRadio IR X?
(synchrotron)
• WindVisible radio
(free-free)
M•
II. The X-ray binary systems
DIFFERENT BINARY SYSTEMS• type of the donor star type of accretion (wind or Roche lobe overflow)
• very different scales:
Every X-ray binary is a
possible microquasar!
J.A. Orosz
VARIABILITY
• Variations = changes in the state of the source
• lightcurves: GX 339-4 / GRS 1915+105
Variations on very different time scales !
“easy” observations for human time scale
X (2-10 keV)
Radio (2,25 GHz)
Rau et al (2003)
GX339-4 lightcurve
1996 2003GRS 1915+105
VARIABILITY : state changes
Fender (2001)Fender (2001)
• Accretion discRadio & X-ray spectrum Radio jet
compact jets
“Classically” : soft X-rays disc (thermal), hard X-rays corona (IC of therm. phot.)
Some state changes transient ejections, ex: off high/soft
states // radio quiet / loud AGNs?
radio – hard X-ray correlation
accretion / ejection coupling
• 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 !
Mirabel et al (1998)
Marscher et al (2002)
III. The different types of jets
COMPACTS JETS
GRS 1915+105
Dhawan et al. (2000) Fuchs et al. (2003)
GRS 1915+105
flat spectrum
optically thick synchrotron emission from radio IR
optically thin synchrotron in X-rays ?
flat or inverted spectrum model:conical jet cut 1/Rmin
shock accelerated e-
Observations : image in radio (difficult: mas. !) or spectrum: radio flat (easier)
Falcke et al. (2002)
SUPERLUMINAL EJECTIONS
• Move on the sky plane ~103 times faster• Jets are two-sided (allow to solve equations max. distance)
same Lorentz factor as in Quasars : ~ 5-10
Mirabel & Rodriguez (1994)
VLA at 3.5 cm
VLBI at 22 GHz ~ 1.3 cm
~ arcsec. scale ~ milliarcsec.
scale
JETS AT LARGE SCALES
• Steady jets in radio at arcminute scale
• Sources found to be nearly always in the low/hard state long-term action of steady jets on the interstellar medium
1E1740.7-2942
GRS 1758-258
VLA at 6 cm
JETS AT LARGE SCALES ex: SS 433 / W50
• SS 433 : variable source 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 !
Vermeulen et al. (1993)
• relativistic ejections at arcsec.-scaleassociated to thermal X-ray emission (Migliari et al. 2002)
• the radio nebula W50 : SN remnantelongated shape (2°x1°~120pc x 60pc) due to jets ?
• Large scale X-ray jets but no motion observedEast part: non-thermal X-ray emission maybe due to jet / ISM interaction
W50
Dubner et al. (1998)
• W50 : > 104 years PJ ~ 1039 erg/s
Ec ~ 1051 erg
W50Radio + X-ray
2° ~120 pc
SS 433
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)
20 Sept. 1998 one day X-ray flare
Hannikainen et al (2001)
Superluminal relativistic ejection (Hannikainen et al. 2001)
VLBI2 –10 keV
XTE J1550-564 : LARGE SCALE X-RAY JETS !
Chandra images 0.3 - 8 keV
23 arcsec
Related to the brief flare of Sept. 1998
Discovery of X-ray sources associated with the radio lobes
• Moving eastern source • Alignment + proper motion
First detection of moving relativistic X-ray jets !
Corbel et al. (2002)
• 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 ?
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 ?
radio Optical (HST) X-ray
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
Marshall et al. (2001)
3C273: quasar (z=0.158) Pictor A: radio galaxy FR IIChandra image + radio (20 cm) contours
Wilson et al. (2001)
Comparison with extragalactic jets
XTE J1550-564
SS433/W50
Spectrum of a Quasar
Synchrotron(jet)
Synchrotron(jet)
thermal(disk)
thermal(disk)
inverse Compton(jet)
Lichti et al. (1994)
Jets are the only truly broad-band sources in the universe (radio-TeV)!Jets are the only truly broad-band sources in the universe (radio-TeV)!
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 emission dominates the X-ray band, the jet has > 90% of the total power
Synchrotron(jet)
Synchrotron(jet)
Synchrotron(jet)
Synchrotron(jet)
thermal(disc)
thermal(disc)
?
• MeV emission due to Synch. Self-Compton from the compact jet ? GeV ? (GLAST)
• shocks with the ISM TeV ?
MICROBLAZARS
• Microblazars = sources with viewing angle < 10°:
- time scales lowered by 22
- flux density increased by 83
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
high mass X-ray binaries + jet sources
interaction of jet with UV photon field from the donor star inverse Compton
• EGRET unidentified sources ? (LS 5039)
IV. Microquasars: sources of TeV
Neutrinos ?
Radio Cores: particle accelerators and high energy laboratories
Blazars emit:
• 511 keV annihilation line
• Gamma-rays
• TeV emission
• TeV neutrinos
microblazars ?
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
_
Neutrino flux predictions for Microquasars
see Distefano et al., ApJ, 2002
• Predicted number of muon events in a km2 detector (for E > 1 TeV):
employing jet parametersinferred from radio observationsof various ejection event! Large uncertainties !! Jet power overestimated by a factor of ~ 10-100
detection
background
+ microblazars: should emitneutrinos with larger flux a way of identification
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 disc emits in the X-rays good propagation in the interstellar medium
• Bipolar jets maximum distance
PROSPECTS
• observation of lines composition of the jets !• observation of microblazars ! • gamma-rays observation: TeV ? jets/ISM interaction?
• TeV neutrino detection
Astrophysics Particle Physics