1. Minnesota Institute for Astrophysics
N Langer PDF
Minnesota Institute for Astrophysics

2. Minnesota Institute for Astrophysics
Georges Lemaître
Came up with a theory of the expansion of the universe, based on Einstein’s GR.
"the Cosmic Egg exploding at the moment of the creation"
Minnesota Institute for Astrophysics

3. Minnesota Institute for Astrophysics
Ylem, the hot cosmic soup at the beginning
George Gamow
Fred Hoyle
Minnesota Institute for Astrophysics

4. Minnesota Institute for Astrophysics
Alas, Gamov could not get past the ‘barrier’ at mass 5.
Mr. Tomkins leaps the mass 5 gap!
Minnesota Institute for Astrophysics

5. Minnesota Institute for Astrophysics
Burbidge, Burbidge, Fowler and Hoyle
Minnesota Institute for Astrophysics

6. Minnesota Institute for Astrophysics

7. Minnesota Institute for Astrophysics
Nuclear Shell Model
Minnesota Institute for Astrophysics

8. Minnesota Institute for Astrophysics

9. Minnesota Institute for Astrophysics

10. Minnesota Institute for Astrophysics

11. Minnesota Institute for Astrophysics

12. Minnesota Institute for Astrophysics

13. Minnesota Institute for Astrophysics
Solar Neutrnio Experiment
Minnesota Institute for Astrophysics

14. Minnesota Institute for Astrophysics

15. Minnesota Institute for Astrophysics
The pp-chain reactions starts at temperatures around 4×106 K making it the dominant energy source in smaller stars.
A self-maintaining CNO chain starts at approximately 15×106 K, but its energy output rises much more rapidly with increasing temperatures.
At approximately 17×106 K, the CNO cycle starts becoming the dominant source of energy. The Sun has a core temperature of around 15.7×106 K, and only 1.7% of 4He nuclei produced in the Sun are born in the CNO cycle.
Minnesota Institute for Astrophysics

16. Minnesota Institute for Astrophysics

17. Minnesota Institute for Astrophysics

18. Minnesota Institute for Astrophysics

19. Minnesota Institute for Astrophysics
Book eqs. 6.25, 6.26
Minnesota Institute for Astrophysics

20. Minnesota Institute for Astrophysics

21. Minnesota Institute for Astrophysics
The half-life of 5Li is 3.7×10−22 s and that of 8Be is 6.7×10−17 s
Need a RESONANCE to up the reaction rate.
The beryllium-8 ground state has almost exactly the energy of two alpha particles.
In the second step, 8Be + 4He has almost exactly the energy of an excited state of 12C.
Minnesota Institute for Astrophysics

22. Minnesota Institute for Astrophysics

23. Minnesota Institute for Astrophysics

24. Minnesota Institute for Astrophysics

25. Minnesota Institute for Astrophysics

26. Minnesota Institute for Astrophysics

27. Minnesota Institute for Astrophysics

28. Minnesota Institute for Astrophysics

29. Minnesota Institute for Astrophysics