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Relativistic Astrophysics: general overview

Lecture 1. Relativistic Astrophysics: general overview. Jean-Pierre Lasota. (a = 2GM/c 2 ). For a neutron star P o = 1.41 a (Haensel, Lasota & Zdunik 1999).

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Relativistic Astrophysics: general overview

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  1. Lecture 1 Relativistic Astrophysics: general overview Jean-Pierre Lasota

  2. (a = 2GM/c2) For a neutron star Po= 1.41 a (Haensel, Lasota & Zdunik 1999)

  3. Einstein A, On a stationary system with spherical symmetry consisting of many gravitating masses, 1939 ANNALS OF MATHEMATICS 40: 922-936 – black holes cannot form Oppenheimer, J. R. & Snyder, H., On Continued Gravitational Contraction, Physical Review, 1939, vol. 56, Issue 5, pp. 455-459 – black holes must form

  4. Maximum masses of neutron stars (Nauenberg & Chapline 1973; Rhoades & Ruffini 1973) . Mmax(rot)=1.18 Mmax Lasota, Abramowicz, Haensel (1996) Salgado, Bonazzola, Gourgoulhon, Haensel (1994)

  5. Richard Tolman

  6. Quasars: Marteen Schmidt 1963 3C 273: a star-like object with large red-shift. 16%

  7. First Texas Symposium on Relativistic AstrophysicsQuasistellar Sources and Gravitational Collapse Austin, December 15-19, 1964

  8. Ed Salpeter (1964) Ya. B. Zeldovich The fate of a star and the release of gravitational energy under accretion Doklady Akademii Nauk SSSR 155, 67-69 (1964) An alternative mechanism of energy emission is examined, in the present note, which is associated with an infall of the external mass in the gravitational field of a collapsing star.

  9. “The idea of infall in a powerful gravitational field as a source of the radiated energy of radiosources was advanced in its most general form by I.S. Shklovsky.” On the Nature of Radio GalaxiesAstronomicheskii Zhurnal, Vol. 39, p.591 (1962) Rees 1984:

  10. The discovery of pulsars (1967), rapidly rotating, strongly magnetized neutron stars changed the attitude of astronomerstowards compact relativistic celestial bodies. Jocelyn Bell

  11. Bohdan Paczyński

  12. LISA sensitivity curve.

  13. “...good science demands that we seek positive evidence in support of the black hole picture, and watch for credible evidence that the standard picture may not be quite right." (Peebles 2002) M=4 1O7 M M 106

  14. EVIDENCE BY: 1. MASS 2. SURFACE 3. Gravitational waves

  15. Galactic Center: Sgr A* (NAOS/Conica-VLT)

  16. Schoedel et al. 2003

  17. QPOs in BH X-ray binaries

  18. Low-mass X-ray binary (LMXB) red dwarf “hot spot” accretion disc ADAF neutron star or black hole

  19. Mass function: Minimum mass of the compact object

  20. Observed masses of neutron-stars and black-holes 1.4 3.0

  21. with surface tburning> tfall

  22. Quiescent (Low-Mass) X-ray transient ADAF DISC ADAF (Advection Dominated Accretion Flows) tradiative-cooling > tinfall

  23. Viscous heating: Advective « cooling »: Radiative cooling: _ F = …. (free-free, Compton, synchrotron) Energy conservation: _ adv adv F = F F ADAF +

  24. . Mquiesc Disc . Log(M) ADAF R(Porb)

  25. A DIFFERENCE BETWEEN NEUTRON STARS AND BLACK HOLES

  26. XMM + Chandra (Lasota 2006)

  27. SPIN “PARADIGM” Radio-loudness of AGNs is related to the (high) value of the BH spin. New observational evidence

  28. Why two AGN looking the same here have different radio (and high energy) properties?

  29. Luminosities: Radio-loudness:

  30. FRII FRI

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