1 / 38

40 Years of Microquasars

40 Years of Microquasars. Ralph Spencer Jodrell Bank Observatory School of Physics and Astronomy University of Manchester Ierapetra June 2014. Radio Emitting X-ray binaries (REXRB). 1968: discovery of radio emission from Sco X-1 (Andrew and Purton 1968)

dane
Télécharger la présentation

40 Years of Microquasars

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 40 Years of Microquasars Ralph Spencer Jodrell Bank Observatory School of Physics and Astronomy University of Manchester Ierapetra June 2014

  2. Radio Emitting X-ray binaries (REXRB) • 1968: discovery of radio emission from Sco X-1 (Andrew and Purton 1968) • 1971: radio emission from X-ray binaries detected by Westerbork Array and GB Interferometer at ~ mJy levels (Braes and Miley 1971, Hjellming and Wade1971) April 1971 John applies to Jodrell Bank for a place on the MSc course, joins in Sept 1971

  3. Cygnus X-3 Goes Bang! • Jan 1972: Detection of Cyg X-3 with GBI (Hjellming and Wade 1972) 0.1-0.3 Jy at 11 and 4 cm • September 1972: –outburst on Cyg X-3 reaching > 20 Jy. Many observatories took part. Gregory et al 1972 Oct 1972 John starts PhD

  4. Nova Monoceros 1975 A0620-00 • Rapid increase in X-ray emission reported by Leicester group (Ariel) • Triggered radio obs at JBO (Davis et al. 1975) • Kuulkers et al. 1999 revisited data Oct 1975 John completes PhD

  5. X-Ray Binaries • ~300 X-ray emitting binary stars (XRBS) found in our own Milky Way galaxy, detected by X-ray satellites at ~1-10 kev (van Paradis 1995, Liu et al. 2000, 2001 catalogues) • High Mass ~ 10 Msun • Low Mass ~ 1 Msun • .All powered by accretion onto a compact object (neutron star or black hole). • Roche Lobe overflow or wind? • ~20 % have been found to have radio emission

  6. Low Mass XRBs • Companions around 1 Msun, with a neutron star or BHC secondary • Neutron star binaries • Type I X-ray bursts • Soft X-ray emission (few kev brightness temp.) • Short orbital period of < 12 hours • BHCs : no Type 1 bursts, hard X-rays, transients • X-ray colour-colour diagram useful diagnostic • Quasi period oscillations in X-ray intensity X-ray bursts from Circ X-1

  7. High Mass X-ray binaries: HMXRB • Indicators: • O, B, Be or Wolf-Rayet stellar spectrum • Strong flaring and absorption variability on a timescale of minutes • Transient outbursts • Hard 1-10 kev spectrum with a power law index at higher energies of ~0-1 • Periods range from 4.8 hrs (Cygnus X-3) to 187 days (Hen 715) • N- star or BHC compact secondaries • Generally wind fed.

  8. The discovery of radio jets • SS433 in 1979 • Moving optical lines suggest precessing jets at 0.26 c with a period of 162.5 days (Abell and Margon1979) • Cambridge 5km observations of compact objects < 1 arcsec, Ryle et al 1978 • Interesting X-ray behaviour – Dennis Walsh suggested we observed it at JB • Discovered extension in PA ~100 deg – jets? (Spencer 1979) Margon and Anderson 1989 MkI-Defford 74-cm 1979 visibility curve

  9. SS433 radio jets • Hjellming and Johnston 1981 VLA results • MERLIN 5 GHz Jowett PhD 1999 Stirling et al 2002

  10. Radio Emission • ~50 sources have radio emission • Most radio emitters are Low Mass XRBs with BHC I. Brown 2006 PhD Thesis

  11. Microquasars • Term first used by Martin Elvis 1984 “Microquasars and the X-ray Background” (Weak AGN) • First used in the context of X-ray binaries: Geldzahler, Fomalont and Cohen 1984, “Sco X-1 The Microquasar” • Now thought to be unrelated background sources VLA 4.8 GHZ

  12. Microquasars • Why microquasar? • Radio jets • Relativistic velocities • Powered by accretion • 106 times closer • Mirabel et al. 1992 1E1740.7-2942

  13. Number of papers with ‘microquasar’ in the title or abstract No. of papers Year

  14. Fundamental plane of black holes • Radio/X-ray correlation found in XRBS can be extended to AGN by the inclusion of a mass term. • Correlation very tight for LLAGN Merloni, Heinz et al. 2003, Falcke, Koerding, Markoff 2004, Koerding et al. 2006

  15. Some Individual Objects • Cygnus X-3 • SS433 • Cygnus X-1 • GRS1915+105 • Cygnus X-2

  16. Cygnus X-3 • Greenbank Interferometer Waltman et al 1995 • 1983 MERLIN 5 GHz – model fitting N-S double showed expansion at 0.3 c Johnston et al. 1983 • Infra red and radio flares Fender, Bell-Burnell, Ogley et al. 1994,1995, 1996, 2001 • 10 Msun WR star and 2.4 Msun BH Zdziarski et al. 2013 Fender et al 1996

  17. Relationship to X-rays • Ryle telescope and RXTE (Pooley) • Quenching of radio before outburst • Hardening of X-rays

  18. Radio/Hard X and γ-ray Quenching • Corbel et al 2012- hard X-rays and γ-rays suppressed just before a major flare

  19. Cygnus X-3 Images • Mioduszewski et al 2001 • 15 GHz VLBA • Evolving N-S jet • 2-sided N-S structure also seen in 5 GHz VLA images (AM). • Expansion at ~0.5 c • (Marti et al 2002) • www.aoc.nrao.edu/~amiodusz/ NB 90 deg rotation

  20. EVN at 5 GHZ 1st e-VLBI observations at 5 GHz Complex changes in the core- more to do!

  21. SS433 • Another WR star and compact companion • 24 Msun WR and 16 Msun BH • 162.5 d precession period • 13 d binary period • Proper motion if at 0.26 c gives distance of 4.6 kpc VLA 5 GHz Blundell and Bowler 2004

  22. The Ruff – Equatorial emission VLA, MERLIN VLBA 6 cm March 1998 Blundell et al 2001 MERLIN+EVN 18 cm June 1998 Stirling et al 2004 Present in ~25% of images, no obvious relationship to jet knots and PA Spencer 2006

  23. W50 and SS433 – the jets slow down? Velocity of filaments in the ears < 0.04c Goodhall et al. 2011 Fit to ephemeris including nutation suggests deceleration at 0.04c/yr Stirling et al. 2004 More observations needed!

  24. Cygnus X-1 – a radio jet in a persistent black hole XRB 15 Msun Black hole +19 Msun O star companion VLBA 8.4 GHz August 1998 -discovery of jet in Cyg X-1 on ~15 mas scale (Stirling et al 2001) VLBA 15 GHz Showing compact jet ~3 mas long Also a weak compact jet in the soft state (Rushton et al 2012 (in low/hard X-ray state)

  25. Optical line emission White: continuum Red: Ha Green: O[III] (Russell, Fender et al. 2007) Cyg X-1 Nebula 1.4 GHz Westerbork image Gallo et al 2005

  26. GRS1915+10510 Msun BH +2 Msun companion Superluminal expansion Mirabel & Rodriguez 1994 Fender et al 1999 0.9c, 11kpc

  27. Radio emission in plateau states (Migliari & Belloni 2003 Xray state χ) Rushton et al 2010

  28. 0.2-0.4 Jy Flares and 0.05-0.1 Jy plateaus Typically 1-3 months

  29. Flares decay in 3-4 days, followed by a suppressed flux before recovering Occurs during plateau state as well as at beginning or end

  30. GRS1915 – log normal flux distribution Compare with power law for Cyg X-3

  31. A Radio Jet in the Cyg X-2 Neutron Star X-ray BinarySpencer et al. MNRAS 435L, 48, 2013 Horizontal Branch (HB) - jet launched here Normal Branch (NB) - mass accretion rate increases Z-track on hardness-intensity diagram Flaring Branch (FB) - unstable nuclear burning on the neutron star 6 cm EVN 22 Feb 2013 Jet ejected SWIFT hardness – intensity diag. Source in HB 23 Feb 2013 Hard Apex - Jet ejected X-ray, UV and radio vs time 1.7 Msun neutron star and a 0.6 Msun companion

  32. To summarise so far • Radio emission can be relatively steady or in flares • Flaring often associated with the formation of relativistic jets on > 100 mas scales • Steady mas (10’s au) jets can also occur • At least one object shows precessing jets • Strong association with X-ray emission: jet-disk coupling • Changing accretion conditions have a causal relationship with the radio jets

  33. q- diagram or Turtles Head Gallo, Fender et al 2005

  34. Miller et al. 2012 model for CygX-1 >0.3c Radio wind 0.3c Reflected X-rays Hard X-rays O Star companion disk Magnetic loops Hot e+- plasma lifted by unstable loops formed by magnetic rotational instability

  35. GRS1915 evolution High Soft X-ray state No radio X-ray Intensity Flaring outburst with relativistic ejection Hardness Dominated by radiation form disk Low Hard X-rays Inner disk instability leads to major ejection Hot corona and jet formed - Blandford Znajek 1977 mechanism Stronger inner jet Weak inner jet Plateau state

  36. Future • Do all galactic XRBs have radio emission at some level? Need much better sensitivity to bring the 20% detections up! • Microquasars in other galaxies e.g. M31 (Middleton et al 2013), IC10 (Bernard et al 2008), NGC300 (Crowther et al. 2010) – should be lots, especially in star forming galaxies. • E.g. an equivalent 10 Jy flare in IC10 from a CygX-3 type object would give 240 microJy on Earth – can be studied with JVLA and e-MERLIN, but not quiescent emission • Relationship to ULXs – extending the fundamental plane • Need the SKA!!

More Related