1. Close binary systems Jean-Pierre Lasota Lecture 1

2.  he light curve of  Persei (Algol) – an eclipsing close binary

3. Al Ghoul

4.  Persei

6. Doppler effect in stellar spectra.

8. Ellipsoidal variations See in Lasota, Scientific American, 280, part no 5, 40-47 (1999)

10. Sizes

11. Tycho’s Nova (in fact a Supernova of type Ia – both novae and SNIa appear in close binaries containing white dwarfs.

13. a Nova outburst

16. The structure of a close binary

20. A black-hole low-mass X-ray binary

21. Outflows

22. A black-hole in a high-mass X-ray binary

23. Black hole X-ray binaries

24. Eclipsing X-ray binaries are very rare

25. Dip Eclipse

26. Dips

27. Types of close binary systems

28. Equipotential surfaces in Roche geometry - Euler equation - Roche potential.. 12

30. Roche lobes

34. Flow of matter on the irradiated surface of a Roche-lobe filling star Coriolis frequency Rossby number V, L – velocity & length scales When Ro << 1 geostrophic flow: rotation important

38. Most close binaries have small eccentricities. This is not true of planets

39. Binary typeCompact objectDonorComment Cataclysmic binaries White dwarfRed dwarf Subtypes : dwarf novae, novae AM CVn binary White dwarf No H Super Soft X-ray Sources White dwarfGiant Supersoft X soucres could be progenitors of SN Ia Ultracompact X-ray Binaries Neutron starWhite dwarf Shortest binary period: 11 min. Low Mass X binaries Neutron star or black hole M, K, G, F dwarfs or ou subgiants All black hole X-ray binaries are transient High Mass X-ray binaries Neutron star or black hole 0,B type supergiants or subgiants The neutron star is often an X-ray pulsar Gamma-ray binaries Neutron star (pulsar)SupergiantDriven by rotation