1. Swift observations of black hole candidate XTE J1752-223 with P. Casella. T.J. Maccarone & P.A. Evans Peter A. Curran Laboratoire AIM, Irfu /Service d'Astrophysique CEA Saclay, France

2. Swift and X-ray transients Gamma-ray burst (GRB) satellite: Burst Alert Telescope (BAT: 15-150 keV) X-ray Telescope (XRT: 0.2-10 keV) Ultraviolet & Optical Telescope (UVOT: UV,U,B,V)

3. Swift and X-ray transients Flexible scheduling Fast pointing Timing & spectral capabilities Quasi-simultaneous observations(0.002-150 keV)

4. Companion Star: cool thermal (nIR-optical-UV) Accretion Disk: warm/hot thermal (optical-X-ray) Corona, Jet: non-thermal (radio, X-ray) All emissions regions probed by Swift

5. XTE J1752-223 Discovered by RXTE on 2009- 10-23 Black-hole candidate with radio-observed jet Observed by RXTE, Swift, Fermi, Suzaku, MAXI, & ground- based optical/radio telescopes ~50 Swift observations over 8 months (Curran et al. 2010)

6. X-ray light curves MAXI 4-10 keV Swift-XRT 0.3-10 keV Swift-BAT 15-150 keV

7. Identifying the states

8. Identifying the states: XRT-BAT spectra Hard (power-law) Soft/thermal XRT BAT

9. Spectral parameters & states hard soft hard intermediate

10. X-ray light curves & states quiescence hard softhard intermediate

11. MAXI light curves 1.5-4 keV 4-10 keV 10-20 keV Matsuoka et al., 2009

12. Hardness Intensity Diagrams

13. XRT BAT/MAXI

14. Hardness Intensity Diagrams XRT BAT/MAXI

15. XRT power spectra

16. Hard state (average) RMS ~54% Soft state (average) RMS <12%

17. XRT power spectra: RMS hard soft hard intermediate

18. XRT power spectra: QPO? QPO? Hard state (average) RMS ~54% Soft state (average) RMS <12%

19. XRT power spectra: QPO? QPO? Hard state (individual sequence)

20. Optical counterpart

21. Counterpart (nIR) IMACS i’ band image Torres et al., 2009

22. Counterpart & sub-arcsec position UVOT v band image DSS image

23. Optical light curve variability

24. Optical – X-ray correlation Early, hard state Soft state & later

25. Optical – X-ray correlation Early, hard state Soft state & later Hysteresis: excess emission due to hard state jet?

26. Counterpart colour? UVOT u-b-v

27. Colour: 0 < β < 4 Counterpart colour?

28. XTE J1752-223: Further work Multi-wavelength spectral fits Radio – nIR/optical/UV – XRT – RXTE – Fermi Multi-wavelength spectral fits Radio – nIR/optical/UV – XRT – RXTE – Fermi

29. Conclusions Swift observations of the first known outburst of XTE J1752-223 allowed us to:  Confirm and refine the epochs of the canonical X-ray states  Confirm the optical counterpart and produce a sub-arcsecond position  Discover an optical - X-ray correlation and hysteresis effect Furthermore, these discussed properties of XTE J1752-223 support its candidacy as a black hole in the Galactic centre region