1. Time Domain Astrophysics Stephen Potter South African Astronomical Observatory

2. Overview What is Time Domain Astrophysics (Astrotomography)?  Variability in Interacting Binaries Cataclysmic Variables  Doppler Tomography  Roche Tomography  Stokes Imaging  Eclipse Mapping SALT first Science  High speed CCD photometry 2

3. Variability in Interacting Binaries –Accretion onto WD in CVs –P orb : minutes – hours –P spin : tens of seconds –Mass accretion events/ outbursts : months –Magnetic cycles : years – decades –WD/inner disc dominate soft X-ray, UV (SALT strength) –Outer disc emission mostly in optical –Mass donor reveals itself in the red/IR –For X-ray binaries (NS/BH)  keV/MeV emission + –variability as fast as milliseconds 3

4. Cataclysmic Variables A.P. Beardmore http://www.astro.keele.ac.uk/~apb/OGL_CV / 4

5. Magnetic Cataclysmic Variables A.P. Beardmore http://www.astro.keele.ac.uk/~apb/OGL_CV / 5

6. Magnetic Cataclysmic Variables A.P. Beardmore http://www.astro.keele.ac.uk/~apb/OGL_CV / 6

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8. Doppler Tomography Schwope et al, 1997, A&A, 319, 894 8

9. Doppler Tomography 9

10. Roche Tomography Potter, Romero-Colmenero, Watson, Buckley, Phillips 2004, MNRAS, 348, 316 10

11. Spectral eclipse mapping Rutten et al. 1993 Nature, 362, 518 11

12. Multi-epoch Doppler Tomography Schwope et al. 2000, MNRAS, 313, 533 12

13. Spin Doppler Tomography 13

14. Steeghs, D., Harlaftis, E.T., Horne, K., 1999, MNRAS, 306, 348 Targets of opportunity Doppler Tomography 14

15. Spectral eclipse mapping Baptista et al. 2000 MNRAS, 314, 727 15

16. Stokes imaging Potter et al. 2004, MNRAS, 348,316 16

17. SALTICAM light curves of SDSS J015543.30+002807.2 17

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