1. Observing Orbital Motion in Strongly Curved Spacetime Institute of Physics, Silesian University in Opava Gabriel Török CZ.1.07/2.3.00/20.0071 Synergy, GAČR 209/12/P740, 202/09/0772, SGS-01-2013, www.physics.cz

2. Observing Orbital Motion in Strongly Curved Spacetime : Institute of Physics, Silesian University in Opava Gabriel Török CZ.1.07/2.3.00/20.0071 Synergy, GAČR 209/12/P740, 202/09/0772, SGS-01-2010, www.physics.cz

3. Timing signatures of accretion disc inhomogeneities Institute of Physics, Silesian University in Opava Gabriel Török CZ.1.07/2.3.00/20.0071 Synergy, GAČR 209/12/P740, 202/09/0772, SGS-01-2013, www.physics.cz

4. COLLABORATION: Pavel Bakala, Didier Barret, Vladimír Karas, Michal Dovčiak, Martin Wildner, Dalibor Wzientek, Marek Abramowicz, Luigi Stella, Eva Šrámková, Kateřina Goluchová, Frederic Vincent, Grzegorz Mazur, Tomáš Pecháček

5. Global Empirical Model of Variability and Spectra (GRS 1915+105, SPL State) Response Matrices (Detector) “DATA” Time and Spectral Distribution of Detected Counts TIMING ANALYSIS RESULTS TOTAL SOURCE FLUX MODEL + Comparing different orbital QPO models, RXTE and LOFT QPO MODEL

6. I. Small spots moving along slightly eccentric orbits close ISCO

7. Left: RXTE Right: LOFT POWER

8. II. Toy models of double peak QPOs assuming preferred orbits

9. Left: RXTE Right: LOFT POWER

10. III. Elongated spots with LOFT [LOFT YELLOW BOOK]

11. CONCLUSIONS Ad SMALL SPOTS: The LOFT observations could easily reveal the Keplerian frequency together with its first and second harmonics when the strongest (but still very weak) single signal is around the limits of the RXTE detectability. Ad ELONGATED SPOTS: The LOFT mission could open a window to observe the epicyclic motion. Ad SPOT vs. TORUS COMPARISON: We conclude that the ability to recognize the harmonic content of the signal and follow the QPO evolution can help to distinguish between the different proposed physical models.