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Microquasars I.F MICROQUASARS I.F. Mirabel (Sap/CEA-Saclay) PROVIDE ANSWERS TO QUESTIONS ON: • The physical nature of relativistic jets seen elsewhere in the universe • A new method to determine distances in astronomy • The connection between accretion and ejection • Evidence for an horizon => black hole NEW PERSPECTIVES: • Determine the origin of black holes knowing the space velocity • Determine the spin of black holes • Ultraluminous non-nuclear X-ray sources in external galaxies • Gain insight into the much more distant GRB afterglows SOURCES OF HIGH ENERGY PHOTONS, PARTICLES, AND NEUTRINOS ? QUASARS & MICROQUASARS Mirabel, Rodriguez, Paul, et al. 1992 QUASAR-MICROQUASAR ANALOGY Mirabel & Rodriguez, Nature, 1998 QUASAR MICROQUASAR • The scales of length and time are proportional to MBH 2 Rsh = 2GMBH/c ∆ α T MBH • The maximum color temperature α of the accretion disk is Tcol ( -1/4 M/10M~) • The maximum synchrotron ν α 1/ frequency of cores MBH 2 5 Μ ? ARE BLACK HOLES WITH MASSES IN THE RANGE OF 10 -10 ~ SUPERLUMINAL MOTIONS IN THE GALAXY Mirabel & Rodriguez (1994) TWO-SIDED GALACTIC JETS MOVE ON THE PLANE OF THE SKY ~103 TIMES FASTER THAN THE ONE-SIDED EXTRAGALACTIC JETS GRS 1915+105: EJECTION EVENTS Rodriguez & Mirabel, 1999 Mirabel & Rodriguez, 1994 cannonballs vs fireballs RELATIVISTIC ABERRATION IN ANTISYMMETRIC TWIN JETS Same bulk Lorentz factors as in QSOs: 2-10 Relativistic upper limit: D < 14 kpc RELATIVISTIC METHOD FOR DISTANCES IN ASTRONOMY FROM PROPER MOTIONS IF THE JETS ARE DOMINATED BY ELECTRON-PROTON PLASMA: FROM DOPPLER FACTOR OF ION LINES •IF ANTISYMMETRIC, THE VELOCITY & DIRECTION OF THE JETS, & THE DISTANCE TO THE SOURCE CAN BE FOUND. •BUT SPECTRAL LINES SO FAR DIFFICULT TO DETECT, EXCEPT SS 433 WHERE H, He, AND Fe LINES ARE FOUND LARGE-SCALE JETS (W50/SS433) λ20cm: (Dubner, Goss, Mirabel); X-rays (Brinkmann,Aschenbach, Kawai) = 60 pc o 1 POWERFUL JETS SEEN IN THE X-RAYS BLOWING UP THE NEBULA W50 AT DISTANCES OF 30 pc. GAMMA-RAYS AND NEUTRINOS FROM MICROQUASARS POHOTON SPECTRA OF SUPERLUMINAL JETS •Association between hard X-rays and jets (Grove et al.) with 1019-22 gr if 1 proton/electron (Mirabel & Rodriguez; Fender et al.) •Gamma-rays may be produced in the jets and dominate the emission above an MeV (Aharonian & Athonian, 1998, 1999) (Kaufman, Romero & Mirabel, 2002) •TeV neutrinos may be produced in outburts if the jets are dominated by electron-proton plasma (Levinson & Waxman, 2001). MICROBLAZARS (Mirabel & Rodriguez, ARAA 1999) Due to relativistic beaming: ∆t α 1/2γ2 ; Ι α 8γ3 e.g. If γ = 5, Θ < 10ο ⇒∆t < 1/50 and ∆I > 103 SHOULD APPEAR AS SOURCES WITH FAST AND INTENSE VARIATIONS OF FLUX ⇒ DIFFICULT TO FOLLOW AND TO FIND First microblazar: V4641 Sgr: a BH in a HMXB γ> 10 Vapp>10c & (Hjellming et al. 2000; Orosz et al. 2001) 20 MICROQUASARS IN THE GALAXY (Mirabel & Rodriguez, ARAA 1999) MICROQUASARS IN EXTERNAL GALAXIES ? ULTRALUMINOUS NON-NUCLEAR X-RAY SOURCES: 40 38 Lx ~ 10 erg/sec when Eddington limit Lx ~ MBH x 10 erg/sec 1) CLAIMED TO BE BLACK HOLES WITH > 100 M~ but none discovered so far in the Milky Way ! 2) MICROQUASARS WITH BEAMED EMISSION (Mirabel & Rodriguez, 1999; King et al. 2001) ULXRs mostly seen in starburst galaxies ⇒ short-lived phase in HMXBs with MBH ~ 10-30 M~ ? GRBs & MICROQUASARS BH PARADIGM MICROQUASARS: JETS DURING TRANSIENT ACCRETION Γ= 2-10 E < 1047 erg. RECURRENT EJECTION EVENTS GRBs: JETS DURING FORMATION OF STELLAR MASS BHs Γ = 200 E ~ 1052 erg . UNIQUE CATASTROPHIC EVENTS BUT IN THE MOST RECENT COLLAPSAR MODELS Γ = 2-10 AT THE BASE OF GRB JETS UNIVERSAL MECHANISM OF JET FORMATION IN MICROQUASARS, AGNs AND GRBs ? COMPACT SYNCHROTRON JETS In accreting black holes (e.g.: Sgr A*,CygX-1, XTE J1118+480, etc.) (Dhawan, Mirabel, Rodriguez) IN LOW/HARD-STATE DIRECT SYNCHROTRON IS MORE POWEFUL IN MICROQUASARS In conical jets: Size α ν-1 (Falcke et al. ) 100 AU 100 MICROQUASAR JETS CONTAIN ELECTRONS WITH Γ ∼ 107 BLACK HOLE IN THE HALO Mirabel , Dhawan , Mignani, Guglielmetti, Rodrigues (Nature, September 13, 2001) o o XTE J1118+480: MBH=7 M~ @ l=158 b=+62 ; D=1.9 kpc Proper Motions: Radio with VLBA Optical on 43 years POSS wrt LSR (km/sec): U = -105 to anticenter V = -98 galactic rotation W = -21 to the plane Vpec=150 km/sec DRIFTING AT HIGH VELOCITY ORBITAL MOTION OF THE BLACK HOLE e=0.6 ; T=40/240 Myr ; Ro=3.8 kpc ; Vpec=220 km/sec ; W=130 km/sec PRESENTLY FLYING THROUGH THE SOLAR NEIGHBORHOOD 1) SHOOT FROM THE PLANE BY AN HIPERNOVA 2 ) RELIC OF A PRISTINE MASSIVE HALO STAR FORMED BEFORE THE DISK POPULATION OF DORMANT BLACK HOLES IN THE HALO Animacion GALACTIC ORBITS OF 8 XRBs (Mirabel & Rodigues, 2002) SCORPIUS X-1: A LMXB FROM THE GALACTIC BULGE CYGNUS X-1 & GRS 1915+105: BLACK HOLES WITH MBH > 10 SOLAR FORM PROMPTLY CELESTIAL ARCHEOLOGY •Black holes in the halo are the fossils of the most massive stars formed during the early phases of evolution of the Galaxy. •.Black holes in the halo may be the remnants of the collapsed massive stars that produced GRBs at z~2. •Important to test the models of black hole formation and kicks by asymmetric supernova explosions •Black holes and neutron stars in the halo related to: 1) a subsample of unidentified EGRET sources, 2) sources of gravitational waves (binary black holes) UNIDENTIFIED EGRET SOURCES (>100 MeV) TWO GALACTIC SUBSAMPLES: 1) Relics from core-collapsed SN correlated with the tilted Gould Belt (Grenier, 1998;Gehrels et al. 2000) 2) Variable, soft and faint population at a scale high of ~2 kpc with a distribution of halo objects (Grenier, 2001) TWO MICROQUASARS IN THE ERROR BOX OF EGRET SOURCES: • LS 5039: A microquasar (Paredes et al. 2000) • LSI+61 303: X-Ray faint (Harrison et al. 2000) • Precessing microblazars (Kaufman, Romero, Mirabel, 2002) ACCRETION AND JET FORMATION ∆ α T MBH Mirabel, Chaty, Rodriguez et al. 1998 JET FORMATION DURING DISAPPEARANCE OF THE INNER DISK EVIDENCE FOR AN HORIZON ⇒ BLACK HOLE QPOs IN MICROQUASARS (Greiner, Belloni, et al) GRS 1915+105 (Strohmayer) Maximum fix frequencies of 40 & 67 Hz repeat ⇒ must depend on fundamental properties of black hole ν ⇒ max = f(MBH, Spin) CAN DETERMINE THE SPIN OF BLACK HOLES PROBLEM: SEVERAL GENERAL RELATIVITY MODELS CONCLUSION Microquasars allow to gain insight into: • THE PHYSICS OF RELATIVISTIC JETS • EVIDENCES FOR HORIZON ⇒ BLACK HOLE • THE CONNECTION BETWEEN ACCRETION DISK INSTABILITIES AND THE FORMATION OF JETS NEW PERSPECTIVES •DETERMINE THE SPIN OF BLACK HOLES • GAIN INSIGHT INTO SUPERLUMINAL X-RAY SOURCES • GAIN INSIGHT INTO GRB AFTERGLOWS • NEW METHOD FOR DISTANCES IN ASTRONOMY •SOURCES OF GAMMA-RAYS AND TeV NEUTRINOS ? .
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