Future Directions in High Resolution Astronomy A Celebration of the 10th Anniversary of the VLBA June 8-12, 2003, Socorro, New Mexico, USA Marc RibóCEA-SACLAY MICROQUASARS

1.Introduction 2.Types of jets 3.State changes and accretion/ejection coupling 4.Astrometry and stellar evolution 5.A search for new microquasars 6.ULXs as microblazars 7.Conclusions OUTLINE

1.Introduction 2.Types of jets 3.State changes and accretion/ejection coupling 4.Astrometry and stellar evolution 5.A search for new microquasars 6.ULXs as microblazars 7.Conclusions OUTLINE

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. X-RAY BINARIES

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 GalaxyNo X-ray pulsars HMXBs 8/131 ( 6%) 8/86 ( 9%) 8/37 (22%) LMXBs35/149 (23%)35/147 (24%)34/142 (24%)

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

MICROQUASARS REXBs displaying relativistic 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 T col  2  10 7 M  1/4. (Mirabel & Rodríguez 1998)

MICROQUASARS REXBs displaying relativistic 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 T col  2  10 7 M  1/4. (Mirabel & Rodríguez 1998) Microquasars had to wait the era of high energy astrophysics

MICROQUASARS : ARTIST’S VIEW

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 ….

1.Introduction 2.Types of jets 3.State changes and accretion/ejection coupling 4.Astrometry and stellar evolution 5.A search for new microquasars 6.ULXs as microblazars 7.Conclusions OUTLINE

COMPACTS JETS: radio GRS Dhawan et al. (2000) Fuchs et al. (2003) GRS flat spectrum emission = optically thick synchrotron from radio  IR flat or inverted spectrum model: conical jet  cut  1/R min shock accelerated e -- Observations : image in radio or spectrum: radio flat Falcke et al. (2002)

ISOLATED (SUPERLUMINAL) EJECTIONS Move on the plane of the sky ~10 3 times faster Jets are two-sided (allow to solve equations  max. distance) Advantage of AGN at <100 Mpc: collimation at R sh (M87, Junor et al )  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

GRO J (VLBA at 1.6 GHz) Hjellming & Rupen (1995) (also Tingay et al. 1995)  = 0.92,  = 85  Aug Aug Aug Sep Sep Sep EPISODIC (SUPERLUMINAL) EJECTIONS

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 JETS WITH NO OUTBURST

  0.17,   80  Persistent nature of the LS 5039 jets thanks to EVN and MERLIN observations on 2000 March 1 (Paredes, Ribó, Ros, Martí, & Massi 2002). 

ONE-SIDED / TWO SIDED JETS CYG X-3 (VLBA at 15 GHz) Mioduszewski et al. (2001)   0.81,   14 

CYG X-3 (VLBA at 15 GHz)   0.81,   14  CYG X-3 (VLA at 5 GHz) Marti et al. (2000) ONE-SIDED / TWO SIDED JETS Mioduszewski et al. (2001)

 = 0.48,  = 73  CYG X-3 (VLA at 5 GHz)

LS I (EVN at 5 GHz) LS I (MERLIN at 5 GHz) Massi et al. (2002) Massi et al. (2001)

ENERGY TRANSFER FROM THE CORE TO THE RADIO JETS Sco X-1 (Global VLBI at 5 GHz) Fomalont et al. (2001)  = 0.45,  = 44  Energy transfer at   0.95

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 1E GRS VLA at 6 cm

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

XTE J : LARGE SCALE X-RAY JETS ! Chandra images keV 23 arcsec Related to the brief flare of Sept 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 ?

Is it a lonely case ? No! XTE J : 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 Angellini & White (2003) XMM-Newton observations of 4U 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.

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 ?

Paragi et al. (1999) Equatorial emission in SS 433: wind-like equatorial outflow or extension of the accretion disk ANOMALOUS EQUATORIAL EMISSION

Equatorial emission with flat spectral index: either thermal radiation or self-absorbed synchrotron. More news soon… Blundell et al. (2001)

1.Introduction 2.Types of jets 3.State changes and accretion/ejection coupling 4.Astrometry and stellar evolution 5.A search for new microquasars 6.ULXs as microblazars 7.Conclusions OUTLINE

Low/Hard High/Soft Grebenev et al. (1993) VARIABILITY: Low/Hard and High/Soft states 2 main X-ray states for the black hole X-ray binaries Correlation between radio and hard X-ray emission Fender, Corbel et al. (1999)

VARIABILITY : state changes Fender (2001) “Classically” : soft X-rays  disc (thermal), hard X-rays  corona (IC of therm. phot.) Some state changes  transient ejections, ex: off  high/soft

VARIABILITY: accretion / ejection coupling cycles of 30 minutes in GRS :  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 ! Mirabel et al. (1998) Marscher et al. (2002)

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) thermal (disc) ? MeV emission due to Synch. Self-Compton from the compact jet ? (GLAST) shocks with the ISM  TeV ?

39 The INTEGRAL mission Launched on October 17, 2002 NEW HORIZONS ON BLACK HOLE ASTROPHYSICS MULTIWAVELENGTH INTEGRAL NETWORK (“MINE”)

R & Dhawan QPO at 2.5 Hz  JEM-X Y.Fuchs (Sap), G. Pooley, S. Trushkin... GRS : INTEGRAL and Multi- P. Goldoni, P. Sizun (SAp)

1.Introduction 2.Types of jets 3.State changes and accretion/ejection coupling 4.Astrometry and stellar evolution 5.A search for new microquasars 6.ULXs as microblazars 7.Conclusions OUTLINE

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 J : a black hole formed ~7 Gyr ago in a Globular Cluster of the Galactic Halo, with v pec =150 km/s (Mirabel et al. 2001). LS 5039: a runaway system with v pec =150 km/s and an amazingly huge linear momentum of ~ 6000 M  km/s !!! (Ribo et al. 2002). Kick? Under study. GRO J : a runaway low-mass black hole formed in a SN explosion with runaway velocity of v pec ~ 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 : a runaway system that lost ~ 90 M  !!! (Rodrigues & Mirabel, submitted). GRS : a black hole formed by prompt collapse? (Dhawan et al. in preparation).

1.Introduction 2.Types of jets 3.State changes and accretion/ejection coupling 4.Astrometry and stellar evolution 5.A search for new microquasars 6.ULXs as microblazars 7.Conclusions OUTLINE

RBSC: X-ray catalog at keV, sources, Voges et al. (1999). NVSS: radio catalog at 1.4 GHz,    40 , 1.8  10 6 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 We recovered all HMXB persistent microquasars except Cyg X-1. THE CROSS-IDENTIFICATION METHOD

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 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 OF RESULTS AFTER OBSERVATIONS

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)

1.Introduction 2.Types of jets 3.State changes and accretion/ejection coupling 4.Astrometry and stellar evolution 5.A search for new microquasars 6.ULXs as microblazars 7.Conclusions OUTLINE

MICROBLAZARS (Mirabel & Rodriguez, ARA&A 1999) Due to relativistic beaming:  t      e.g. If  = 5,       t 10 3 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 V app >10c &   (Hjellming et al. 2000; Orosz et al. 2001)

PRECESSING MICROBLAZARS Possible gamma-ray sources by inverse Compton of the electron jets and external photon fields Kaufman-Bernado, Romero, Mirabel (A&A, 2002) Romero, Kaufman-Bernado, Mirabel (A&A, 2002) Cyg X-1 MAY BE A PRECESSING MICROBLAZAR Possible gamma-ray transients seen by BATSE (Golenetskii et al & Scmidt 2002) One-sided jet with possible variable ejection angle (Stirling et al. 2001) V > 0.5c with    transient lasting a few hours

UNIDENTIFIED EGRET SOURCES (>100 MeV) 1)Relics from core-collapsed SN correlated with the tilted Gould Belt (Grenier, 1998;Gehrels et al. 2000) TWO MICROQUASARS IN THE ERROR BOX OF EGRET SOURCES: TWO GALACTIC SUBSAMPLES (Grenier, 2001) 2) Variable, soft and faint population at a scale high of ~2 kpc with a distribution of halo objects LS 5039 (Paredes et al. 2000) LS I (Kniffen et al. 1997)  QSO CANDIDATES ARE HMXBs JET SOURCES (Paredes et al; Romero et al.)

ULTRALUMINOUS X-RAY SOURCES Microquasars in external galaxies ? X-ray (Chandra) Antennae Fabbiano et al.

SUPER-EDDINGTON X-RAY SOURCES SHORT-LIVED HMXBs (MICROQUASARS) ? WITH ANYSOTROPIC EMISSION: BEAMED (Mirabel & Rodriguez, 1999) ANISOTROPIC BUT NOT NECESARILY BEAMED (King et al. 2001) WITH ISOTROPIC EMISSION BUT M BH > 60 M  (Pakul et al. 2002) MULTIWAVELENGTH OBSERVATIONS (Ward et al ) M82 seen by Chandra L x ~ erg/sec when Eddington limit L x ~ M BH x erg/s INTERMEDIATE MASS BHs > 200 M  ? claimed by NASA press releases. However: Photon spectra similar to Galactic stellar-mass black holes Mostly seen in starburst galaxies (e.g. The Antennae) Where such Intermediate-mass BHs would accrete from ? Why none was found in the Milky Way ?

First radio counterpart of a ULX Chandra ATCA: source + radio contours In the NGC 5408 galaxy: HST image Kaaret et al. (2003) Origin of this ULX : X-ray spectrum + radio and optical counterpart: compatible with beamed emission from a relativistic jet (angle < 10°)  First extragalactic microblazar ??? Intermediate mass black holes in question ? ULX

1.Introduction 2.Types of jets 3.State changes and accretion/ejection coupling 4.Astrometry and stellar evolution 5.A search for new microquasars 6.ULXs as microblazars 7.Conclusions OUTLINE

Some major questions about jets What fraction of the total power output of compact objects is in jets versus radiated energy? Are jets electron/proton or electron/positron? Are jets purely accretion powered or can jets extract energy from the rotation of a bh? How are jets formed and collimated? What is the role of magnetic fields? Are jets re-energized at large distances from origin?

CONCLUSIONS Microquasars allow to gain insight into: THE PHYSICS OF RELATIVISTIC JETS AND THE INTERACTION WITH THE ISM THE CONNECTION BETWEEN ACCRETION DISK INSTABILITIES AND THE FORMATION OF JETS CONSTRAIN THE ORIGIN AND EVOLUTION OF BHs NEW PERSPECTIVES DETERMINE THE SPIN OF BLACK HOLES (QPOs) GAIN INSIGHT INTO ULTRALUMINOUS X-RAY SOURCES DEEPER SURVEYS TO DISCOVER NEW SOURCES GAIN INSIGHT INTO GRB AFTERGLOWS ? SOURCES OF GAMMA-RAYS AND TeV NEUTRINOS ?