580 likes | 698 Views
Future Directions in High Resolution Astronomy A Celebration of the 10th Anniversary of the VLBA June 8-12, 2003, Socorro, New Mexico, USA. MICROQUASARS. Marc Ribó CEA-SACLAY. OUTLINE. Introduction Types of jets State changes and accretion/ejection coupling
E N D
Future Directions in High Resolution Astronomy A Celebration of the 10th Anniversary of the VLBA June 8-12, 2003, Socorro, New Mexico, USA MICROQUASARS Marc Ribó CEA-SACLAY
OUTLINE • Introduction • Types of jets • State changes and accretion/ejection coupling • Astrometry and stellar evolution • A search for new microquasars • ULXs as microblazars • Conclusions
OUTLINE • Introduction • Types of jets • State changes and accretion/ejection coupling • Astrometry and stellar evolution • A search for new microquasars • ULXs as microblazars • Conclusions
X-RAY BINARIES An X-ray binary is a binary system containing a compact object (either a neutron star or a stellar-mass black hole) accreting matter from the companion star. The accreted matter carries angular momentum and on its way to the compact object usually forms an accretion disk, responsible for the X-ray emission. A total of 280 X-ray binaries are known (Liu et al. 2000, 2001). High Mass X-ray Binaries (HMXBs). Optical companion with spectral type O or B. Mass transfer via decretion disk (Be stars) or via strong wind or Roche-lobe overflow (OB SG). There are 131 known HMXBs. Low Mass X-ray Binaries (LMXBs). Optical companion with spectral type later than B. Mass transfer via Roche-lobe overflow. 149 known LMXBs.
X-RAY BINARIES An X-ray binary is a binary system containing a compact object (either a neutron star or a stellar-mass black hole) accreting matter from the companion star. The accreted matter carries angular momentum and on its way to the compact object usually forms an accretion disk, responsible for the X-ray emission. A total of 280 X-ray binaries are known (Liu et al. 2000, 2001). High Mass X-ray Binaries (HMXBs). Optical companion with spectral type O or B. Mass transfer via decretion disk (Be stars) or via strong wind or Roche-lobe overflow (OB SG). There are 131 known HMXBs. Low Mass X-ray Binaries (LMXBs). Optical companion with spectral type later than B. Mass transfer via Roche-lobe overflow. 149 known LMXBs.
Radio Emitting X-ray Binaries (REXBs) are X-ray binaries that display radio emission, interpreted as synchrotron radiation. Around 43 of the known 280 X-ray binaries (15%) are REXBs, including 8 HMXBs and 35 LMXBs. Abundances: Total Galaxy No X-ray pulsars HMXBs 8/131 ( 6%) 8/86 ( 9%) 8/37 (22%) LMXBs 35/149 (23%) 35/147 (24%) 34/142 (24%)
QUASARS MICROQUASARS Quasar 3C 223 Microquasar 1E1740.7-2942 VLA at 1477MHz ~ 20 cm radio (VLA) observations at 6 cm Mirabel et al. (1992)
MICROQUASARS REXBs displayingrelativistic radio jets. Compact object may be a Neutron Star or a Black Hole (BH). In BH, the length and time scales are proportional to the mass, M. The maximum color temperature of the accretion disk is Tcol2107M1/4. (Mirabel & Rodríguez 1998)
MICROQUASARS REXBs displayingrelativistic radio jets. Compact object may be a Neutron Star or a Black Hole (BH). In BH, the length and time scales are proportional to the mass, M. The maximum color temperature of the accretion disk is Tcol2107M1/4. (Mirabel & Rodríguez 1998) Microquasars had to wait the era of high energy astrophysics
Each source is interesting by itself. Only 15 confirmed cases with resolved jets, but probably all REXBs are microquasars!
Why study jets ? • Outflows may be important for the structure of accretion flow. • Jets may dissipate a large fraction of the total accretion energy. • Jets may be a source of light element nucleosynthesis • …. • They look cool ….
OUTLINE • Introduction • Types of jets • State changes and accretion/ejection coupling • Astrometry and stellar evolution • A search for new microquasars • ULXs as microblazars • Conclusions
COMPACTS JETS: radio Observations : image in radio or spectrum: radio flat Fuchs et al. (2003) Dhawan et al. (2000) flat spectrum GRS 1915+105 GRS 1915+105 flat or inverted spectrum model: conical jet cut 1/Rmin shock accelerated e-- emission = optically thick synchrotron from radio IR Falcke et al. (2002)
ISOLATED (SUPERLUMINAL) EJECTIONS same Lorentz factor as in Quasars : ~ 5-10 VLBI at 22 GHz ~ 1,3 cm VLA at 3,5 cm ~ arcsec. scale ~ milliarcsec. scale Mirabel & Rodriguez (1994) • Move on the plane of the sky ~103 times faster • Jets are two-sided (allow to solve equations max. distance) • Advantage of AGN at <100 Mpc: collimation at 30-100 Rsh (M87, Junor et al. 1999)
EPISODIC (SUPERLUMINAL) EJECTIONS GRO J1655-40 (VLBA at 1.6 GHz) 18-19 Aug. 1994 22-23 Aug. 1994 25-26 Aug. 1994 1-2 Sep. 1994 8-9 Sep. 1994 12-13 Sep. 1994 = 0.92 , = 85 Hjellming & Rupen (1995) (also Tingay et al. 1995)
PERSISTENT JETS WITH NO OUTBURST VLBA+VLA map of LS 5039 at 5 GHz (Paredes et al. 2000). The asymmetry in the brightness of the components, and in their distance to the core, can be explained by Doppler boosting, implying: 0.15 , 81 The jet seems to be persistent, because radio emission is always detected at similar levels as the ones found when this map was obtained.
Persistent nature of the LS 5039 jets thanks to EVN and MERLIN observations on 2000 March 1 (Paredes, Ribó, Ros, Martí, & Massi 2002). 0.17 , 80
ONE-SIDED / TWO SIDED JETS CYG X-3 (VLBA at 15 GHz) 0.81 , 14 Mioduszewski et al. (2001)
ONE-SIDED / TWO SIDED JETS CYG X-3 (VLBA at 15 GHz) 0.81 , 14 CYG X-3 (VLA at 5 GHz) Mioduszewski et al. (2001) Marti et al. (2000)
CYG X-3 (VLA at 5 GHz) = 0.48 , = 73
LS I +61 303 (EVN at 5 GHz) Massi et al. (2001) LS I +61 303 (MERLIN at 5 GHz) Massi et al. (2002)
ENERGY TRANSFER FROM THE CORE TO THE RADIO JETS Sco X-1 (Global VLBI at 5 GHz) = 0.45 , = 44 Energy transfer at 0.95 Fomalont et al. (2001)
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
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)
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
Is it a lonely case ? No! XTE J1748-248: a cosmic jet hits the wall ? (Hjellming, unpublished). Jet/ISM interaction ? The jets stoped when it possibly hits a cloud. Radio (VLA)
A fossil X-ray jet in 4U 1755-33 • XMM-Newton observations • of 4U 1755-33 in 2000 • (in quiescence since 1995). • Large (7’) scale two-sided • X-ray jets. • BHC active for > 25 years. • If v=c, it would have taken • 13 yr to extend to its current • length. Angellini & White (2003)
SUMMARY ABOUT 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 ?
ANOMALOUS EQUATORIAL EMISSION Equatorial emission in SS 433: wind-like equatorial outflow or extension of the accretion disk Paragi et al. (1999)
Equatorial emission with flat spectral index: either thermal radiation or self-absorbed synchrotron. More news soon… Blundell et al. (2001)
OUTLINE • Introduction • Types of jets • State changes and accretion/ejection coupling • Astrometry and stellar evolution • A search for new microquasars • ULXs as microblazars • Conclusions
High/Soft Low/Hard VARIABILITY: Low/Hard and High/Soft states • 2 main X-raystates for the black hole X-ray binaries • Correlation between radio and hard X-ray emission Grebenev et al. (1993) Fender, Corbel et al. (1999)
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 • Fender (2001)
VARIABILITY: 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 phenomenon in the quasar 3C 120 ? far slower !
thermal(disc) 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 • MeV emission due to Synch. Self-Compton from the compact jet ? (GLAST) • shocks with the ISM TeV ? Markoff et al. (2001) If jet emission dominates the X-ray band, the jet has > 90% of the total power
39 The INTEGRAL mission Launched on October 17, 2002 NEW HORIZONS ON BLACK HOLE ASTROPHYSICS MULTIWAVELENGTH INTEGRAL NETWORK (“MINE”)
Y.Fuchs (Sap), G. Pooley, S. Trushkin ... R & Dhawan QPO at 2.5 HzJEM-X P. Goldoni, P. Sizun (SAp) GRS 1915+105: INTEGRAL and Multi-
OUTLINE • Introduction • Types of jets • State changes and accretion/ejection coupling • Astrometry and stellar evolution • A search for new microquasars • ULXs as microblazars • Conclusions
Astrometry and Stellar Evolution…… before GAIA • Two options for the final stages of the progenitor of the compact object: • Mass loss or kick produce changes in the orbital parameters • runaway binary systems. • Prompt collapse produces no runaway. • Approach: • Radial velocity curve provides radial velocity of the system. • VLBI, HST or archives provide the proper motions in the plane of the sky. • Classic methods in astronomy (also VLBI parallaxes!) provide the distance. • With all this information we can compute the space velocity. Assuming a mass model for the Galaxy we can compute the Galactocentric orbit of the system!
Up to now: XTE J1118+480: a black hole formed ~7 Gyr ago in a Globular Cluster of the Galactic Halo, with vpec=150 km/s (Mirabel et al. 2001). LS 5039: a runaway system with vpec=150 km/s and an amazingly huge linear momentum of ~ 6000 M km/s !!! (Ribo et al. 2002). Kick? Under study. GRO J1655-40: a runaway low-mass black hole formed in a SN explosion with runaway velocity of vpec ~ 120 km/s and linear momentum of 550 M km/s, as seen in neutron star systems with kicks (Mirabel et al. 2002). Sco X-1: a runaway system formed in a Globular Cluster (Mirabel & Rodrigues 2003). Cyg X-1: a high-mass black hole formed by prompt collapse, or formed in the dark, with no SN explosion (Mirabel & Rodrigues 2003). LS I +61 303: a runaway system that lost~ 90 M !!! (Rodrigues & Mirabel, submitted). GRS 1915+105: a black hole formed by prompt collapse? (Dhawan et al. in preparation).
OUTLINE • Introduction • Types of jets • State changes and accretion/ejection coupling • Astrometry and stellar evolution • A search for new microquasars • ULXs as microblazars • Conclusions
THE CROSS-IDENTIFICATION METHOD • RBSC: X-ray catalog at 0.1-2.4 keV, 18806 sources, Voges et al. (1999). • NVSS: radio catalog at 1.4 GHz, 40, 1.8106 sources, Condon et al. (1998). • We assumed reasonable selection criteria for sources with b 5 and 40 • (NVSS limit) and ended up with a sample containing 17 sources. • Among them: • 4 already known sources: • The well known microquasars LS 5039, SS 433 and Cyg X-3 • The new microquasar LS I +61 303. We recovered all HMXB persistent microquasars except Cyg X-1.
SUMMARY OF RESULTS AFTER OBSERVATIONS Summary of the obtained results after the VLA, optical and EVN+MERLIN observations. An asterisk indicates a non-expected behavior for microquasars. (Paredes, Ribó, & Martí 2002) (Ribó, Ros, Paredes, Massi, & Martí 2002)
SUMMARY SUMMARY OF RESULTS AFTER OBSERVATIONS Summary of the obtained results after the VLA, optical and EVN+MERLIN observations. An asterisk indicates a non-expected behavior for microquasars. (Paredes, Ribó, & Martí 2002) (Ribó, Ros, Paredes, Massi, & Martí 2002) Optical spect. (Martí, Paredes, Bloom, Casares, Ribó, & Falco submitted)
SUMMARY SUMMARY OF RESULTS AFTER OBSERVATIONS Summary of the obtained results after the VLA, optical and EVN+MERLIN observations. An asterisk indicates a non-expected behavior for microquasars. (Paredes, Ribó, & Martí 2002) (Ribó, Ros, Paredes, Massi, & Martí 2002) Optical spect. (Martí, Paredes, Bloom, Casares, Ribó, & Falco submitted)
OUTLINE • Introduction • Types of jets • State changes and accretion/ejection coupling • Astrometry and stellar evolution • A search for new microquasars • ULXs as microblazars • Conclusions
MICROBLAZARS (Mirabel & Rodriguez, ARA&A 1999) Due to relativistic beaming: Dt a 1/2g2 ; I a 8g3 e.g. If G = 5, Q< 10o Dt < 1/50 and DI > 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 Vapp>10c & G> 10(Hjellming et al. 2000; Orosz et al. 2001)