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Difficulties with the QPOs resonance model. Jean-Pierre Lasota’s Birthday Conference 2007. by Paola Rebusco. Lekcja pierwsza. Wiedzie ć , ż e wiemy to co wiemy i wiedzie ć , ż e nie wiemy tego czego nie wiemy, oto prawdziwa wiedza. Miko ł aj Kopernik. First Lesson.
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Difficulties with the QPOs resonance model Jean-Pierre Lasota’s Birthday Conference 2007 by Paola Rebusco
Lekcja pierwsza Wiedzieć, że wiemy to co wiemy i wiedzieć, że nie wiemy tego czego nie wiemy, oto prawdziwa wiedza. Mikołaj Kopernik
First Lesson Wiedzieć, że wiemy to co wiemy i wiedzieć, że nie wiemy tego czego nie wiemy, oto prawdziwa wiedza. Mikołaj Kopernik To know that we know what we know, and to know that we do not know what we do not know, that is true knowledge. Nicolaus Copernicus
High frequency (kHz) QPOs M. van der Klis 2000 T. Strohmayer 2001 • In Black Holes: stable • In Neutron Stars: the peaks move-much more rich phenomenology (state, spin, Q) 1/M scaling -> orbital motion 3:2…although not always
Difficulties according to… “I do not believe in your model” Jean-Pierre Lasota
Difficulties according to… • Outsiders: Tomaso Belloni • Insiders: A&K Team
Outsiders 1)NEUTRON STARS “The biggest limit of the model is that it does not work” T.B. • The two frequencies are in 3:2 ratio, but they are related in such a way that they move away from the 3:2 ratio. • = spin or spin/2 (NO!Mendez&Belloni 2007) • No explanation of the direct observables (NO MODEL DOES)
What is wrong with the Bursa line? (32)(3+2)=65!
Outsiders 2)BLACK HOLES • Stable • 3:2, [ GRS 1915+150 (5:3)..] “on those small numbers” (4) “the model works”TB
Insiders - BH vs NS • Different modulation (see Michal Bursa’s talk) • Different excitation • Different mechanism (Outsider)?
Insiders- SIMULATIONS • Slender tori slightly out of equilibrium do not produce QPOs (only transient - Mami Machida) • They do if the torus is kicked HOWEVER it is difficult to recognize the modes (Omer Blaes, Chris Fragile, Mami Machida, Eva Sramkova)
Insiders - EXCITATION MECHANISM • Direct forcing (NS rotation?but spin) • Stochastic forcing (BH?) • Disk instabilities (Mami Machida’s simulations: P&P instability)
Insiders - DAMPING • Stochastic damping ?!? • What controls the coherence Q= /? Didier Barret et al. - Qlow>Qhigh - Qlow increases with and drops
Insiders - EPI or NOT EPI?!? • EPI: - Pressure and gravity coupling? NO!!!(slender torus-Jiri Horak)… the advantage is that they survive to damping - non axisymmetric modes?NO • NOT EPI: - the eigenfreq. depend on thermodynamics -> 1/M ?!? - g-modes (but do not survive) which modes are special?
Modes and Spin (A&K, Michal Bursa, Eva Sramkova, Odele Straub) Kerr geometry Method 1= Ramesh Narayan group Method 2= Middleton Group
Is it the end? • Thin disks Non - constant l • a and