Scientific goal in Nuclear Astrophysics is to explore:

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1 Nuclear Physics in Stars Michael Wiescher University of Notre Dame Joint Institute for Nuclear Astrophysics Scientific goal in Nuclear Astrophysics is to explore: Nuclear Signature in the Cosmos The Nuclear Engine of Stellar Evolution & Stellar Explosion The Origin of the Elements The Origin of Life? A network of international JINA A network of international JINA collaborations for achieving this goal

2 time Nucleosynthesis History

3 Signatures of Nucleosynthesis The origin and formation of the elements is the main signature for nuclear physics in the Universe! The light emission of stars and stellar explosions reflects the role of stars as nuclear power plants! Abundan nce galactic abundance distribution stellar H-, He, C, O, Si-burning cosmic rays stars, supernovae s-process He-burning in AGB stars, massive stars p-process site disputed r-process type II supernovae, merging neutron stars A

4 Cosmo-Chemistry of Meteorites AGB-Stars Supernovae Novae

5 Spectroscopy surveys of stars in our and far distant galaxies Observation of nucleosynthesis products th through h ssurvey and nd d detailed t il d analysis! n l sis! ARC 2.5m SDSS Telescope (3 deg FOV)

6 Light and Light-Curves Light intensity correlates with energy-output Light curve follows the radioactive decay law 56 Ni, 56 Co, 44 Ti

7 The (radio) active Universe COMPTEL INTEGRAL 1 MeV-30 MeV γ-radiation in Galactic Survey ( 26 Al Half life: 700,0000 years) 44 Ti in Supernova Cas-A Location (Half life: 60 years)

8 Stars & Stellar Explosions are Cosmic Cauldrons

9 Nuclear processes are the engine of the Universe! the looks Nuke-2009 and the engine

10 Simulation of stellar processes in laboratory environment Comparison with observational results and Comparison with observational results and interpretation through computer modeling

11 Nuclear Reactions in Stars generate energy create new isotopes and elements p N C γ 12 C(p,γ) 13 N reaction probability σ: reaction cross section (in unit barns=10-24 cm 2 ) 11

12 Nuclear burning & stellar evolution 10 Si-ignition O-ignition iti Ne-ignition 9 C-ignition log (T c ) He-ignition 8 H-ignition log (ρ c ) Each burning phase is determined by nuclear reactions in terms of energy generation, time scale nucleosynthesis

13 Neutrinos from the Sun Neutrino Sources in the Sun: 1 H(p,e - ν) 2 H (total) 3 He(3He,2p) 4 He (pp-i) 3 He(α,γ) 7 Be (pp-ii 7 Be(p,γ) 8 B (pp-iii) 14 N(p,γ) 15 O (CNO) Neutrino detectors Borexino, Gran Sasso, Italy SNO, Canada, and Superkamiokande, k Japan

14 Reactions in red Giant Stars

15 The last Days of Stellar Burning ng dissolution of burning shells and mixing of matter with as yet unforeseeable consequences! Convective Boundary Burning Zones Dave Arnett; Santa Barbara, The last Days of Burning

16 Massive Stars Collapse re-bounce and shock driven by neutrino wind pressure

17 r-process production of heavy elements in supernova shock Abundance distribution in metal-poor (old) galactic halo stars matches solar r-process abundances! unique r-process site!

18 Detection of 60 Fe with INTEGRAL 60 Fe enrichment in deep sea iron manganese sediments Observation of 60 Fe by radioactive decay t 1/2 =1.5 Myr

19 Observational evidence for a nearby Supernova Myr ago at a distance of ~10pc! The oldest walking human ancestor Australopithecus afarensis

20 Nucleosynthesis in supernova shock Important model parameter for abundance predictions masses, shell closures T 1/2, P n, (n,γ) & ν-processes! Production of ~50% of heavy elements

21 X-Ray Bursts as Nuclear Laboratory

22 HCNO & rp-process

23 Elements in our Galaxy

24 Astrobiology At bil in Cosmic Bombardment NASA astrobiology observation program

25 New Initiatives: Cosmic Ray Simulations Accelerators provide 5 MeV Radiation distribution interactioni Bombardment of asteroid material leads to the formation of complex organic molecules, the first step to LIFE - Astrobiology

26 Each heavy atom in our body was build and processed through ~40 supernova explosions since the beginning of time! W d f ff We are made of star stuff Carl Sagan