Early History: The Beginnings 1900: Discovery of gamma rays by Villard

1. Historical Perspective • For theory highlights, see excellent review by Satula and Wyss: Rep. Prog. Phys. 68, 131 (2005) • Technological milestones not included • Early History: The Beginnings • 1900: Discovery of gamma rays by Villard • 1910: Bragg shows that gammas are rays • 1914: Rutherford and Andrade measure wavelengths (crystal diffraction). • Rutherford coins the name ‘gamma rays’ • 1924: Pauli suggests that hyperfine splitting is related to deformed nuclei • 1935: Schüler and Schmidt measure nuclear quadrupole moment (Casimir 1936) • 1936: Bohr’s paper on the deformed nuclear liquid drop. Vibrations. • 1937: Bohr and Kalckar. Rotations and the moment of inertia • 1938: Teller and Wheeler. Rotations. • 1939: Fission and shape degrees of freedom (Meitner & Frisch, Bohr & Wheeler)

2. Age of Discovery • 1948: Nuclear shell model (Jensen and Goeppert-Mayer) • 1950: Deformed shell model (Rainwater) • 1951: Particle+rotor model; intrinsic system (A. Bohr) • 1952: Nuclear Jahn-Teller effect (particle-vibration coupling) • Rotational states in the actinides • 1953: Unified model (Bohr & Mottelson, Hill & Wheeler) • Coulomb excitation • 1954: Cranking model • 1955: Nilsson model (Nilsson and Moszkowski) • Intensity (Alaga) rules • 1958: Shell-model description of nuclear rotation: Elliott’s SU(3) model. Band termination • Nuclear superconductivity (Bohr-Mottelson-Pines, Belyaev) • 1960: Coriolis anti-pairing • 1961: Systematic calculations of moments of inertia (with pairing) • 1962: Discovery of fission isomers • 1963: Observation of 10+ state with alpha beam • 1964: Shell energy • 1965: Observation of 20+ state with heavy-ion beam • 1967: Theory of shell correction; prediction of superdeformation

3. Vocabulary, Learning the Rules of the Game • Fundamentals of shell model tested • Basic collective modes characterized • Unified model extremely successful • Simple geometric and algebraic schemes introduced • Useful labels to characterize states and phenomena • Powerful phenomenology developed • Can interpret basic features of nuclear response to high spin • Tools of trade mastered • Data systematized • but… • Only qualitative understanding (e.g., MOI) • Lacking microscopic understanding rooted in interaction • …Labeling is not equivalent to understanding… • 1969: “Nuclear Structure vol. I” by B&M • Superheavy magic numbers • 1970: First cranked HFB calculations • 1971: Backbending observed • 1972: Rotational alignment • 1974: Rotating liquid drop model • Interacting Boson Model introduced • Yrast traps (high-K isomers) found • 1975: Signature quantum number • “Nuclear Structure vol. II” by B&M • 1976: Rotating shell correction approach. Prediction of high-spin superdeformation • 1979: Cranked Shell Model. Angular momentum alignment. Quasiparticle diagrams • 1981: Prediction of uniform rotation around non-principal axis • 1983: Terminating bands predicted in heavy nuclei (observed 1984) • Discovery of a nuclear reflection-asymmetric rotor • 1984: Theory of reflection-asymmetric nuclear rotors • Discovery of the scissors mode • 1985: Rotational quasi-continuum studied • 1986: Discovery of high-spin superdeformation • Rotational damping predicted • 1988: Deep inelastic spectroscopy introduced • 1990: Discovery of identical bands • 1991: Discovery of magnetic rotation • First g.s. g-factor measurement in light neutron-rich nuclei using fast beams • 1993: Shears mechanism and explanation of magnetic rotation. Realization that • deformations can be associated with currents. • 1995: Gammasphere construction completed

4. Vocabulary, learning the rules of the game • 1969: “Nuclear Structure vol. I” by B&M • Superheavy magic numbers • 1970: First cranked HFB calculations • 1971: Backbending observed • 1972: Rotational alignment • 1974: Rotating liquid drop model • Interacting Boson Model introduced • Yrast traps (high-K isomers) found • 1975: Signature quantum number • “Nuclear Structure vol. II” by B&M • 1976: Rotating shell correction approach. Prediction of high-spin superdeformation • 1979: Cranked Shell Model. Angular momentum alignment. Quasiparticle diagrams • 1981: Prediction of uniform rotation around non-principal axis • 1983: Terminating bands predicted in heavy nuclei (observed 1984) • Discovery of a nuclear reflection-asymmetric rotor • 1984: Theory of reflection-asymmetric nuclear rotors • Discovery of the scissors mode • 1985: Rotational quasi-continuum studied • 1986: Discovery of high-spin superdeformation • Rotational damping predicted • 1988: Deep inelastic spectroscopy introduced • 1990: Discovery of identical bands • 1991: Discovery of magnetic rotation • First g.s. g-factor measurement in light neutron-rich nuclei using fast beams • 1993: Shears mechanism and explanation of magnetic rotation. Realization that • deformations can be associated with currents. • 1995: Gammasphere construction completed How are complex systems built from a few, simple ingredients? - Shell Structure - Pairing - Collective modes What leads to simple excitations and regularities in complex systems? -Dynamical Symmetries -Critical Point Symmetries The Limits of nuclear existence? -Drip-lines -Superheavy elements

5. Modern Era • 1995: Relativistic Coulex of light neutron-rich nuclei • 1996: Extreme s.p. SM picture of high-spin superdeformations • 1998: Prompt proton decay of a well-deformed rotational band • 1999: High-spin states of the heaviest elements • 2001: Rotating proton emitters • 2002: Superdeformed wobblers • Deep-inelastic studies of neutron-rich nuclei (-decays with prompt gammas) • Coulex with heavy neutron-rich ISOL beams • Important SD-yrast link in 152Dy found • First g-factor measurement on isomers in heavy neutron-rich nuclei with fast beams • 2003: Shell structure with two-proton knockout (gammas with knockout residues) • 2005: First nuclear moment measurement with radioactive beams by the recoil-in- • vacuum technique • Pygmy and GDR around 132Sn • Multiple Coulex with heavy proton-rich ISOL beams • Transfer in inverse kinematics with ISOL beams using -particle • coincidences and particle- angular correlations • 2006: Discrete states in 58Ni at E=42 MeV, E~4.4 MeV • Gamma ray spectroscopy used as a powerful tool • Life at the limits is demanding: many triggers required • Coupling of angular momentum with isospin extremely successful • Addressing basic questions of the nuclear many-body problem • Probing unique features of the polarized system • Contributions across disciplines • Applications? • From Quantity to Quality