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Exotic Nuclei and the Nucleonic Matter Witold Nazarewicz (UT/ORNL)

Exotic Nuclei and the Nucleonic Matter Witold Nazarewicz (UT/ORNL) West High School, Knoxville, Dec. 20, 2006. Introduction The building blocks The nucleus The landscape The nucleonic matter Exotic nuclei: why are they important? The limits of existence The superheavies

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Exotic Nuclei and the Nucleonic Matter Witold Nazarewicz (UT/ORNL)

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  1. Exotic Nuclei and the Nucleonic Matter Witold Nazarewicz (UT/ORNL) West High School, Knoxville, Dec. 20, 2006 • Introduction • The building blocks • The nucleus • The landscape • The nucleonic matter • Exotic nuclei: why are they important? • The limits of existence • The superheavies • Nuclei and the Cosmos • Exotic nuclei at UT/ORNL • Summary

  2. How do protons and neutrons make stable nuclei and rare isotopes? What is the origin of simple patterns in complex nuclei? What is the equation of state of matter made of nucleons? What are the heaviest nuclei that can exist? When and how did the elements from iron to uranium originate? How do stars explode? What is the nature of neutron star matter? How can our knowledge of nuclei and our ability to produce them benefit the humankind? Life Sciences, Material Sciences, Nuclear Energy, Security Questions that Drive the Field Physics of nuclei Nuclear astrophysics Applications of nuclei

  3. superheavy nuclei proton drip line neutron drip line Nuclear Landscape 126 stable nuclei 82 r-process known nuclei terra incognita 50 protons 82 rp-process neutron stars 28 20 50 8 28 neutrons 2 20 8 2

  4. Shells 10 experiment experiment 0 Nuclei theory -10 Shell Energy (MeV) theory 0 20 28 50 -10 discrepancy 82 126 0 diff. 1 experiment -10 20 60 100 Number of Neutrons 0 58 92 198 138 -1 Shell Energy (eV) Sodium Clusters spherical clusters theory 1 0 -1 deformed clusters 50 100 150 200 Number of Electrons

  5. Change of Shell Structure in Neutron Rich Nuclei Near the drip lines nuclear structure may be dramatically different. First experimental indications demonstrate significant changes No shell closure for N=8 and 20 for drip-line nuclei; new shells at 14, 16, 32

  6. Neutron Drip line nuclei 6He 4He 8He HUGE D i f f u s e d PA IR ED 5He 7He 9He 10He

  7. Out-law nuclei of the nuclear borderland

  8. n n p p p n Skins and Skin Modes

  9. What are the limits of atoms and nuclei?

  10. Liquid-drop energy 264108 8 4 0 310126 -4 298114 -8 -0.4 0 0.4 0.8 b2

  11. region of spherically shell stabilised nuclei („island of stability“) 208Pb region of deformed shell stabilised nuclei around Z=108 and N=162

  12. lifetimes > 1y Superheavy Elements S. Cwiok, P.H. Heenen, W. Nazarewicz Nature, 433, 705 (2005)

  13. Crazy topologies of superheavy nuclei…

  14. rods Self-consistent calculations confirm the fact that the “pasta phase” might have a rather complex structure, various shapes can coexist, at the same time significant lattice distortions are likely and the neutron star crust could be on the verge of a disordered phase. Liquid crystal structure? deformed nuclei Skyrme HF with SLy4, Magierski and Heenen, Phys. Rev. C 65, 045804 (2002)

  15. Based on National Academy of Science Report [Committee for the Physicsof the Universe (CPU)] Question 3How were the elements from iron to uranium made ?

  16. RIA intensities (nuc/s) Mass known > 1012 102 1010 10-2 Half-life known nothing known 10-6 106 Nuclear Input (experiment and theory) Masses and drip lines Nuclear reaction rates Weak decay rates Electron capture rates Neutrino interactions Equation of State Fission processes Supernova E0102-72.3 n-Star KS 1731-260 How does the physics of nuclei impact the physical universe? • What is the origin of elements heavier than iron? • How do stars burn and explode? • What is the nucleonic structure of neutron stars? X-ray burst p process s-process 4U1728-34 331 330 Frequency (Hz) r process 329 328 327 10 15 20 Time (s) rp process Nova Crust processes T Pyxidis stellar burning protons neutrons

  17. r (apid neutron capture) process The origin of about half of elements > Fe(including Gold, Platinum, Silver, Uranium) Supernovae ? Neutron star mergers ? Open questions: • Where does the r process occur ? • New observations of single r-process events in metal poor stars • Can the r-process tell us about physics under extreme conditions ? Swesty, Calder, Wang

  18. neutron capture timescale: ~ 0.2 ms Rapid neutroncapture b-decay Seed Equilibrium favors“waiting point” (g,n) photodisintegration Proton number Neutron number The r-process

  19. Accreting neutron stars Neutron star(H and He burninto heavier elements) Companion star(H + He envelope) Accretion disk(H and He fallonto neutron star)

  20. X-ray bursts (1735-444) 15 s ms burst oscillations Off-state Lum. 4U1728-34 KS 1731-260 331 330 Frequency (Hz) 329 NASA/Chandra/Wijnands et al. Superbursts 328 327 (4U 1735-44) 10 15 20 Time (s) StrohmayerBhattacharyya et al. 2004 6 h 18 18.5 time (days) Lines during bursts EXO0748-676 Cottam, Paerels, Mendez 2002 Deciphering observations of Hubble, CHANDRA …

  21. Nuclear Structure and Reactions Nuclear Theory forces methods extrapolations low-energy experiments Nuclear Astrophysics

  22. Applications: Science for the Betterment of Mankind “One of the frontiers of our science is to manipulate nuclei to create new elements and isotopes both for science and, eventually, for societal needs. Often, the applications rely on our ability to select specific nuclei with particular decay modes, half-lives, and energies. Perhaps most importantly, the field provides a superb venue for the important mission to educate and train the next generation of nuclear scientists, who will play key roles not only in basic research itself, but in myriad applied fields”. From : White Paper on the Intellectual Challenges of RIA, prepared for Dr. R. Orbach LENP generates over 40% of PhDs in nuclear science • Human Health • Environment, Geosciences, Oceanography,.. • Nuclear Energy • Food & Agriculture • Material Sciences • Chemistry and Biology • History, Art, Archeology • National Security: • Stewardship of the Nations Nuclear Weapons Stockpile • Homeland Security/Non-Proliferation • Diagnostics for High Energy Density Physics Facilities

  23. a-emitters for therapy

  24. 5*106 2 days later the mice have been devided into 4 groups: First in vivo experiment to demonstrate the efficiency of alpha targeted therapy using 149Tb produced at ISOLDE, Summer 2001

  25. Targeted Alpha Therapy (TAT) in vivo – direct evidence for single cancer cell kill using 149Tb-Rituximab G.-J. Beyer, M. Miederer, S. Vranješ-Đurić, J.J. Čomor, G. Künzi, O. Hartley, R. Senekowitsch-Schmidtke, D. Soloviev, Franz Buchegger and the ISOLDE Collaboration, Eur.J.Nucl.Med. and Molecular Imaging 33(4), 547-554, (2004)

  26. Polonium-210 is an alpha emitter that has a half-life of 138.376 days; it decays directly to its daughter isotope 206Pb. A milligram of 210Po emits as many alpha particles per second as 5 grams of 226Ra. A single gram of 210Po generates 140 watts of power. Because it emits many alpha particles, which are stopped within a very short distance in dense media and release their energy, 210Po has been used as a lightweight heat source to power thermoelectric cells in artificial satellites; for instance, 210Po heat source was also used in each of the Lunokhod rovers deployed on the surface of the Moon, to keep their internal components warm during the lunar nights. Weight-for-weight, polonium is around 5 million times more toxic than hydrogen cyanide (the oral LD50 for 210Po is about 50 ng compared to about 250 mg for hydrogen cyanide). The main hazard is its intense radioactivity (as an alpha emitter), which makes it very difficult to handle safely. It is also chemically toxic (with poisoning effects analogous with tellurium). Even in microgram amounts, handling 210Po is extremely dangerous, requiring specialized equipment and strict handling procedures. Alpha particles emitted by polonium will damage organic tissue easily if polonium is ingested, inhaled, or absorbed (though they do not penetrate the epidermis and hence are not hazardous if the polonium is outside the body). -Po

  27. QCD • Origin of NN interaction • Many-nucleon forces • Effective fields subfemto… nano… Complex Systems Giga… Cosmos femto… Physics of Nuclei Quantum many-body physics Nuclear Astrophysics • In-medium interactions • Symmetry breaking • Collective dynamics • Phases and phase transitions • Chaos and order • Dynamical symmetries • Structural evolution • Origin of the elements • Energy generation in stars • Stellar evolution • Cataclysmic stellar events • Neutron-rich nucleonic matter • Electroweak processes • Nuclear matter equation of state • How does complexity emerge from simple constituents? • How can complex systems display astonishing simplicities? How do nuclei shape the physical universe?

  28. The study of nuclei remains a forefront area of science. Huge discovery potential Merit Relevant to many other fields and applications RIA is required advance the science in the next decade. Summary RIA: Connecting Nuclei with the Universe

  29. BACKUP SLIDES

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