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Ron Ekers Southern Cross Astrophysics Conference #1 Hydro Majestic
15-20 June 2008




Sterl Phinney
­ "Black holes are the most beautiful objects in the Universe"

Dick Manchester
­ "The best timing on any pulsar on any telescope at any time" ­ "pulsar timing is immune from the effects of global warming" ­ "why does it have to be Eddington anyway, it accretes from plane and ejects along axis" ­ answer - so we can calculate black hole mass



Michael Brown
­ "both models are likely to be incorrect but they are still very popular"



Matt Jarvis
­ "this is now a very famous correlation based on limited data"

Bill Coles
­ "this a well understood problem that doesn't need Baysian techniques"




Mark Lacy - high z radio galaxies and SMBH
­ radio galaxies contain really big BH (108-9) this is just the mass range which is detected by pulsar timing



models the SMBH merger rate (Wen) what is measured (George Hobbs)
­ MBH mass function and merger rate ­ problem is how to separate these effects



black hole merger recoil kicks (Joan Centrella)






any em counterpart gives a standard candle at cosmological distances (Benz Kocsis) gravity waves for radio astronomers (Sterl Phinney)
­ just replace strain by amplitude

ISS phenomena first recognised by pulsars (Barney Rickett)
­ Interpretation initially strongly opposed by AGN astronomers ­ an example of innovation through cross fertilization



another perspective from an electrical engineer (Bill Coles) impact of the Parkes mutibeam receiver (Marta Burgay)




Warren Brown 2006, found a main sequence star moving at 850km/s
­ distribution of hyper velocity stars supports continuous ejection for the last 250Myr



Chiaki Kobayashi - chemicodynamical evolution
­ many stars form in dwarf galaxies before massive galaxies form ­ That's where the old stars come from



Use pulsar separation to build a time machine




In mid 1990 a few non AGN objects beyond z=3, now 1000's some process truncates star formation in massive halo's
­ AGN feedback?






all methods to investigate SMBH at higher redshift need an AGN on at least one SMBH component as tracers visible at high z jets can give both positive and negative feedback SMBH and galaxy growth are linked so need feedback Laura Blecha notes that recoil requires a paradigm shift
­ feedback is dramatically effected by recoil ­ notes that young people adapt faster to a paradigm shift ­ this is expected because older scientists loose the advantage of accumulated knowledge



AGN as evidence for mergers?




Great review by Sterl Phinney Mbh v Mbulge relation

­ Its this relation that requires a link between the SMBH mass and the whole galaxy, hence need for feedback ­ line width + virialized + reverberation mapping ­ the many problems where outlined by Matt Jarvis ­ Peng z=2 sample with careful modelling of AGN
» SMBH relatively more massive than bulge » hence SMBH first and galaxy assembly later



only AGN can be used to explore the redshift dependence

­ sub mm galaxies are a problem - opposite dependence with redshift


Do AGN follow the Mbh v M
­ looks OK (Matt Jarvis)

bulge

relation?




pc scale radio jets probe close to the SMBH
­ ­ ­ ­ ­ mildly relativistic in vol limited sample highly relativistic in flux limited samples due to boosting some show re-orientation some show plasma running corners what about Occam's Razor?



M87 jet asymmetry needs 0.5 to 1c but observe 0.02c
­ intrinsically one sided! ­ is all asymmetry in AGN jets due to Doppler boosting?



X sources ­ two models
­ Proposes a combined model for X sources with backflow filling the old cavity caused by previous ejection before axis re-orientation



all radio galaxies with large HI envelopes are small (few kpc) radio galaxies population of double radio sources associated with spirals at high z 50 objects not seen in deep Spitser fields




Most radio galaxies have impressive alignment! Maybe they are the single SMBH and the binary SMBH are not radio galaxies!




special session




examples are very rare color mag plot also shows no merger effect QSO host colours need ages 2-3Gyrs so not very consistent with mergers FRI's dont need mergers but the FRII's do No clear indication from HI of a major merger in radio galaxy sample




numerical GR is an exciting and expanding field
­ first attempt in 1964 - failed then and for another 40years

Need for coincident GW and EM observations
­ ­ ­ ­ identification Eddington ratio cosmology Black hole physics periodic accretion huge energy in gravity wave so any coupling to plasma will give effects sudden mass loss gives shocks X-ray after glow when gas falls back in recoil flares



possible electromagnetic effects
­ ­ ­ ­ ­



need to start coordination for search plans




many tantalising examples but generally the binary explanation is not unique NGC6240 double Xray source double profile QSO
­ very large samples available for searching

0402+379 double AGN (VLBI) periodic flux variability
­ claims made summarised by Stephanie Komossa ­ eg OJ287 modelled by Valtonen but the predicted peak did not occur
» modified model to fit data



VLBI astrometry to see the orbit Double rotation measures New at this conference: use of scintillations to find double AGN
­ sub pc scale is easily accessible, peak in structure function at sub day time scales




distribution of kicks for interesting parameter space
­ mass ratio effects tricky and relations not yet known ­ early days but work in progress ­ we already know that astrophysically significant velocities will occur



need an em signature to see the recoiling SMBH
­ hence it needs an accretion disk: ­ recoiling SMBH carries the disk with it ­ bound SMBH oscillating through disk



recoiling SMBH signatures
­ off nuclear QSO can be spatial or kinematics ­ velocity offsets between QSO and host galaxy
» search in Sloan SDSS found one good source with 2650km/s



Laura Blecha discussed oscillating bound SMBH
­ carries disk for the first Gyr then get burst every plane crossing

recoil flares




backgrounds or sources Sterl Phinney
­ 109 solar mass SMBH dominates GW background ­ mass ratio cancels in total merger ­ at z<2 (in Sesana model)



Joris and George almost set a new limit
­ sensitivity curves as a function of GW frequency
» peak sensitivity is at 1/obs time

­ includes jumps, red noise and does statistics better ­ right at "predicted" level


Need to analyses detection probability v source distance and mass
­ now 1010 Mo at modest z ­ future 109 Mo at any z




Huge advances in survey instruments 1014 flux sensitivity improvement in 40 years of GW astronomy
­ radio 107 in similar time scale



LISA
­ revolutionary for SMBH research ­ complimentary to pulsar GW detection



New pulsar searches and timing essential for gravity wave research
­ FAST 500m spherical dish ­ Arecibo 305m




a bound re-coiling SMBH periodic plunges through the disk of the galaxy
­ will maintain its spin axis so gets a new accretion disk each plunge



maybe the bend is the merging event with re-orientation
PKS0637-752 ­ Quasar with Xray/radio jet