Sin ttulo de diapositiva

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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
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OUTLINE

• Introduction
• Types of jets
• State changes and accretion/ejection coupling
• Astrometry and stellar evolution
• A search for new microquasars
• ULXs as microblazars
• Conclusions

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OUTLINE

• Introduction
• Types of jets
• State changes and accretion/ejection coupling
• Astrometry and stellar evolution
• A search for new microquasars
• ULXs as microblazars
• Conclusions

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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.
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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.
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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)
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QUASARS ? MICROQUASARS
Quasar 3C 223
Microquasar 1E1740.7-2942
radio (VLA) observations at 6 cm
VLA at 1477MHz 20 cm
Mirabel et al. (1992)
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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 Tcol ? 2?107 M?1/4. (Mirabel Rodríguez
1998)
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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 Tcol ? 2?107 M?1/4. (Mirabel Rodríguez
1998)
Microquasars had to wait the era of high energy
astrophysics
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MICROQUASARS ARTISTS VIEW
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Each source is interesting by itself. Only 15
confirmed cases with resolved jets, but probably
all REXBs are microquasars!
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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 .

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OUTLINE

• Introduction
• Types of jets
• State changes and accretion/ejection coupling
• Astrometry and stellar evolution
• A search for new microquasars
• ULXs as microblazars
• Conclusions

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COMPACTS JETS radio
Observations image in radio or
spectrum radio flat
Fuchs et al. (2003)
Dhawan et al. (2000)
flat spectrum
GRS 1915105
GRS 1915105
flat or inverted spectrum model conical jet ?
?cut ? 1/Rmin shock accelerated e--
emission optically thick synchrotron from
radio ? IR
Falcke et al. (2002)
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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 lt100 Mpc collimation at
  30-100 Rsh (M87, Junor et al. 1999)

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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)
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PERSISTENT JETS WITH NO OUTBURST
VLBAVLA 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.
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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?
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ONE-SIDED / TWO SIDED JETS
CYG X-3 (VLBA at 15 GHz)
? ? 0.81 , ? ? 14?
Mioduszewski et al. (2001)
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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)
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CYG X-3 (VLA at 5 GHz)
? 0.48 , ? 73?
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LS I 61 303 (EVN at 5 GHz)
Massi et al. (2001)
LS I 61 303 (MERLIN at 5 GHz)
Massi et al. (2002)
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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)
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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
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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)
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XTE J1550-564 LARGE SCALE X-RAY JETS !
Chandra images 0.3 - 8 keV
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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)
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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 gt 25 years.
• If vc, it would have taken
• 13 yr to extend to its current
• length.

Angellini White (2003)
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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 ?

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ANOMALOUS EQUATORIAL EMISSION
Equatorial emission in SS 433 wind-like
equatorial outflow or extension of the
accretion disk
Paragi et al. (1999)
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Equatorial emission with flat spectral
index either thermal radiation or
self-absorbed synchrotron. More news soon
Blundell et al. (2001)
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OUTLINE

• Introduction
• Types of jets
• State changes and accretion/ejection coupling
• Astrometry and stellar evolution
• A search for new microquasars
• ULXs as microblazars
• Conclusions

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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

Grebenev et al. (1993)
Fender, Corbel et al. (1999)
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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)
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VARIABILITY accretion / ejection coupling
Mirabel et al. (1998)
Marscher et al. (2002)

• cycles of 30 minutes in GRS 1915105
• 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 !

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Spectrum of a Microquasar
If jet emission extends up to the visible band,
the jet has gt 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 gt 90 of the total power
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The INTEGRAL mission
Launched on October 17, 2002 NEW HORIZONS ON
BLACK HOLE ASTROPHYSICS
MULTIWAVELENGTH INTEGRAL NETWORK (MINE)
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GRS 1915105 INTEGRAL and Multi-?
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OUTLINE

• Introduction
• Types of jets
• State changes and accretion/ejection coupling
• Astrometry and stellar evolution
• A search for new microquasars
• ULXs as microblazars
• Conclusions

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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!

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Up to now XTE J1118480 a black hole formed 7
Gyr ago in a Globular Cluster of the Galactic
Halo, with vpec150 km/s (Mirabel et al.
2001). LS 5039 a runaway system with vpec150
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 1915105 a black hole formed by
prompt collapse? (Dhawan et al. in preparation).
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OUTLINE

• Introduction
• Types of jets
• State changes and accretion/ejection coupling
• Astrometry and stellar evolution
• A search for new microquasars
• ULXs as microblazars
• Conclusions

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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?, 1.8?106
  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.

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SUMMARY OF RESULTS AFTER OBSERVATIONS
Summary of the obtained results after the VLA,
optical and EVNMERLIN observations. An asterisk
indicates a non-expected behavior for
microquasars. (Paredes, Ribó,
Martí 2002) (Ribó, Ros, Paredes, Massi, Martí
2002)
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SUMMARY
SUMMARY OF RESULTS AFTER OBSERVATIONS
Summary of the obtained results after the VLA,
optical and EVNMERLIN 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)
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SUMMARY
SUMMARY OF RESULTS AFTER OBSERVATIONS
Summary of the obtained results after the VLA,
optical and EVNMERLIN 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)
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OUTLINE

• Introduction
• Types of jets
• State changes and accretion/ejection coupling
• Astrometry and stellar evolution
• A search for new microquasars
• ULXs as microblazars
• Conclusions

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MICROBLAZARS (Mirabel Rodriguez, ARAA 1999)

• Due to relativistic beaming Dt a 1/2g2 I
  a 8g3
• e.g. If G 5, Q lt 10o ? Dt lt 1/50 and DI
  gt 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
• Vappgt10c G gt 10 (Hjellming et
  al. 2000 Orosz et al. 2001)

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PRECESSING MICROBLAZARS
Possible gamma-ray sources by inverse Compton of
the electron jets and external photon fields
Kaufman-Bernado, Romero, Mirabel (AA,
2002) Romero, Kaufman-Bernado, Mirabel (AA,
2002)

• Cyg X-1 MAY BE A PRECESSING MICROBLAZAR
• Possible gamma-ray transients seen by BATSE
  (Golenetskii et al. 2002 Scmidt 2002)
• One-sided jet with possible variable ejection
  angle (Stirling et al. 2001)
• V gt 0.5c with Q lt 10o ? transient lasting a few
  hours

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UNIDENTIFIED EGRET SOURCES (gt100 MeV)
TWO GALACTIC SUBSAMPLES (Grenier, 2001)

• Relics from core-collapsed SN correlated with
• the tilted Gould Belt (Grenier, 1998Gehrels et
  al. 2000)

2) Variable, soft and faint population at a scale
high of 2 kpc with a distribution of halo
objects
TWO MICROQUASARS IN THE ERROR BOX OF EGRET
SOURCES
LS 5039 (Paredes et al. 2000) LS I 61 303
(Kniffen et al. 1997)
mQSO CANDIDATES ARE HMXBs JET SOURCES (Paredes et
al Romero et al.)
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ULTRALUMINOUS X-RAY SOURCESMicroquasars in
external galaxies ?
Antennae
Fabbiano et al.
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SUPER-EDDINGTON X-RAY SOURCES
M82 seen by Chandra

• Lx 1040 erg/sec when Eddington limit Lx MBH
  x 1038 erg/s
• INTERMEDIATE MASS BHs gt 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 ?

SHORT-LIVED HMXBs (MICROQUASARS) ? WITH
ANYSOTROPIC EMISSION BEAMED (Mirabel
Rodriguez, 1999) ANISOTROPIC BUT NOT NECESARILY
BEAMED (King et al. 2001) WITH ISOTROPIC EMISSION
BUT MBH gt 60 M? (Pakul et al. 2002)
MULTIWAVELENGTH OBSERVATIONS (Ward et al.
2001-03)
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First radio counterpart of a ULX
In the NGC 5408 galaxy HST image
ATCA source radio contours
Chandra
ULX
Kaaret et al. (2003)

• Origin of this ULX
• X-ray spectrum radio and optical counterpart
• compatible with beamed emission from a
  relativistic jet (angle lt 10)
• ? First extragalactic microblazar ???
• Intermediate mass black holes in question ?

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OUTLINE

• Introduction
• Types of jets
• State changes and accretion/ejection coupling
• Astrometry and stellar evolution
• A search for new microquasars
• ULXs as microblazars
• Conclusions

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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?

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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 ?