Nuclear Physics Over The Years: From the high spin era to rare isotopes

Sep 19, 2025, 8:00 AM → Sep 20, 2025, 2:35 PM America/New_York

Sun Flower Room (Friday Conference Center, UNC Chapel Hill)

CELEBRATING THE CAREER AND CONTRIBUTIONS OF ROBERT V. F. JANSSENS

This symposium explores the rich evolution of nuclear physics, tracing its trajectory from the high-spin era to the current frontier of rare isotope research. Anchored around the career and contributions of Robert V. F. Janssens, the event provides a lens into the transformation of experimental nuclear physics over the past several decades. 

The symposium will highlight the era of high-spin phenomena, when advances in gamma-ray spectroscopy enabled the mapping of complex nuclear structures and the discovery of exotic rotational behaviors in nuclei. It will showcase how these foundational studies paved the way for deeper questions about the nature of nuclear matter, symmetries, and collective motion. 

Transitioning into the era of rare isotopes, the symposium will examine how the development of rare isotope beam facilities and cutting-edge detector technologies has expanded the nuclear landscape, enabling precise studies of nuclei far from stability. These explorations inform our understanding of astrophysical processes, nuclear forces, and the limits of nuclear existence. 

Through scientific presentations and discussions, the symposium will contextualize how Robert’s work contributed to these shifts, including his role in advancing experimental techniques, mentoring the next generation of scientists, and fostering collaborations that have propelled the field forward.

The symposium will begin on Friday, September 19, and conclude at midday on Saturday, September 20, 2025 at the Friday Center.

Registration is FREE.

This event is jointly sponsored by the Triangle Universities Nuclear Laboratory (TUNL) and the Department of Physics and Astronomy, University of North Carolina at Chapel Hill. 

 

 

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Friday, September 19

8:30 AM → 8:50 AM Session 0: Open Ceremony

Convener: Akaa Ayangeakaa (University of North Carolina at Chapel Hill / TUNL)

8:30 AM Welcome Remarks by the Chair, Department of Physics and Astronomy, UNC

Speaker: Prof. Fabian Heitsch (University of North Carolina at Chapel Hill)

8:40 AM Welcome Remarks by the TUNL Director

Speaker: Prof. Calvin Howell (Duke University)

8:50 AM → 10:15 AM Session 1: High spin collectivity & superdeformation

This session will explore the breakthroughs that emerged from the study of high-spin states in nuclei, a field that transformed our understanding of collective motion, rotational bands, and superdeformation. Presentations will reflect on how advanced gamma-ray spectroscopy and detector arrays enabled detailed mapping of nuclear shapes and configurations at extreme angular momenta, providing insights into the underlying shell structures and symmetry-breaking phenomena that govern collective behavior in the atomic nucleus.

Convener: Dr Paul Fallon (LBNL)

8:50 AM Superdeformation at ATLAS: from the Notre Dame BGO Array to GRETINA

Speaker: Dr Michael Carpenter (Argonne National Laboratory)

Session1-T1.pdf

9:10 AM Exotic Nuclear Structure under the Microscope - Seeing ‘AYEBALL to AYEBALL’ with Robert

Speaker: Prof. Patrick Regan (University of Surrey)

Session1-T2.pdf

9:30 AM Taking Nuclei for a Spin

Speaker: Prof. Partha Chowdhury (University of Massachusetts, Lowell)

Session1-T3.pdf

9:50 AM A High-Spin Journey with Robert

Speaker: Prof. Daryl Hartley (United States Naval Academy)

Session1-T4.pdf

10:15 AM → 10:35 AM Symposium Photo and Coffee Break

Coffee Break

10:35 AM → 12:20 PM Session 2: Neutron-rich nuclei – Single particle aspects

Focusing on the single-particle properties of neutron-rich nuclei, this session will discuss how experiments with transfer reactions and knockout techniques have provided precision data on single-particle energies, spectroscopic factors, and occupancy, reshaping shell model interpretations for isotopes far from stability. Talks will highlight how these studies have uncovered the role of weak binding and continuum effects, leading to evolving shell structures and changes in traditional magic numbers in neutron-rich systems.

Convener: Dr Calem Hoffman (Argonne National Laboratory)

Session2-T0.pdf

10:35 AM States, Levels, and Excitations in Weakly Bound Nuclei

Speaker: Dr Ben Kay (Argonne National Laboratory)

Session2-T1.pdf

10:55 AM Solenoidal Spectrometers for Nuclear Reaction Studies

Speaker: Prof. Alan Wuosmaa (University of Connecticut)

Session2-T2.pdf

11:15 AM Dipping a toe into the neutron-rich waters of the fp-shell

Speaker: Prof. Sean Freeman (The University of Manchester)

Session2-T3.pdf

11:35 AM Unveiling exotic features in neutron-rich nuclei with direct reactions

Speaker: Dr Ritu Kanungo (TRIUMF)

Session2-T4.pdf

11:55 AM The Thrill of Searching for Hidden Shell Gaps Together

Speaker: Prof. Bogdan Fornal (Institute of Physics of the Polish Academy of Sciences)

Session2-T5.pdf

12:20 PM → 1:15 PM Lunch Break

Lunch Break

1:15 PM → 2:40 PM Session 3: The Nucleus as a Probe of Various Fundamental Processes

This session will focus on various experimental techniques and the opportunities they provide to probe with renewed precision aspects as varied as the search for physics beyond the standard model, the importance of masses for nucleosynthesis, the opportunity to test QCD in nuclei or the continued search for new symmetries.

Convener: Dr Mitch Allmond (ORNL)

1:20 PM From the ANL-Notre Dame BGO Array to the Ultimate Compton Suppression.

Speaker: Dr David Radford (Oak Ridge National Laboratory)

Session3-T1.pdf

1:40 PM Trapped at Argonne

Speaker: Dr Jason Clark (Argonne National Laboratory)

Session3-T2.pdf

2:00 PM Probing the Neutron-Neutron Interaction and the Structure of the Neutron at Low Energies

Speaker: Dr Calvin Howell (Duke University & TUNL)

Session3-T3.pdf

2:20 PM Gammasphere experiments with Robert: examples from a herculean effort

Speaker: Dr Walter Reviol (Argonne National Laboratory)

Session3-T4.pdf

2:40 PM → 3:00 PM Coffee Break

Coffee Break

3:00 PM → 4:25 PM Session 4: Production and features of exotic nuclei

Addressing the production, identification, and characterization of exotic nuclei, this session will cover advances in rare isotope beam facilities and experimental techniques that have expanded the nuclear landscape. Talks will showcase methods for producing nuclei near and beyond the drip lines, highlight the unique decay modes and structure phenomena observed in these systems, and discuss how these efforts contribute to refining nuclear models and understanding fundamental interactions in exotic systems.

Convener: Dr Gordon Ball (TRIUMF)

Session4-T0.pdf

3:05 PM Highlights in the neutron-rich Ni isotopes

Speaker: Prof. Benjamin Crider (Mississippi State Universit)

Session4-T1.pdf

3:25 PM The Quest for the Driplines

Speaker: Prof. Bradley Sherrill (FRIB/MSU)

Session4-T2.pdf

3:45 PM Building the Facility for Rare Isotope Beams

Speaker: Prof. Thomas Glasmacher (FRIB/MSU)

Session4-T3.pdf

4:05 PM Marrying In‑Beam and Decay Spectroscopy to Reveal the Structure of Exotic Nuclei

Speaker: Dr Dariusz Seweryniak (Argonne National Lab)

Session4-T4.pdf

4:25 PM → 4:45 PM Coffee Break

4:45 PM → 6:10 PM Session 5: Nuclear Astrophysics

This session will connect nuclear physics with astrophysical environments, examining how nuclear reactions and structure studies inform stellar processes and nucleosynthesis pathways. Presentations will cover experimental and theoretical investigations of key reactions relevant to stellar burning and explosive scenarios, providing insights into the origin of elements in the universe and the critical nuclear data needed for astrophysical modeling.

Convener: Prof. Julieta Gruszko (University of North Carolina at Chapel Hill & TUNL)

4:50 PM Open nuclear systems in Structure and Astrophysics

Speaker: Prof. Ingo Wiedenhoever (Florida State University)

Session5-T1.pdf

5:10 PM To TUNL and beyond! Robert's contributions to studying the cosmos at TUNL

Speaker: Prof. Richard Longland (North Carolina State University)

Session5-T2.pdf

5:30 PM Spectroscopy for Astrophysics in the Janssens Era

Speaker: Dr Kelly Chipps (Oak Ridge National Laboratory)

Session5-T3.pdf

5:50 PM The Isoscalar Giant Monopole Resonance in Exotic Nuclei and the Asymmetry Term of Nuclear Incompressibility

Speaker: Prof. Umesh Garg (University of Notre Dame)

Session5-T4.pdf

6:10 PM → 6:45 PM Reception

6:45 PM → 9:45 PM Dinner: Retirement Reception

Conveners: Dr Donald Geesaman (Argonne National Laboratory), Prof. Mark Riley (Florida State University)

Janssens_2025.pdf

Saturday, September 20

8:00 AM → 9:00 AM Breakfast and Networking

9:00 AM → 10:25 AM Session 6: Neutron-rich nuclei – Shape coexistence

This session will focus on the phenomenon of shape coexistence in neutron-rich nuclei, where multiple distinct shapes can coexist at low excitation energies within the same nucleus. Presentations will illustrate how Coulomb excitation, lifetime measurements, and in-beam spectroscopy have revealed detailed shape transitions, collective excitations, and the interplay of deformation-driving orbitals, enhancing our understanding of structural evolution in isotopes with extreme neutron-to-proton ratios.

Convener: Prof. Reyco Henning (University of North Carolina at Chapel Hill & TUNL)

Session6-T0.pdf

9:05 AM Connecting Shape Coexistence at Spin 0 to Superdeformation at High Spins

Speaker: Prof. Silvia Leoni (Università degli Studi di Milano and INFN)

Session6-T1.pdf

9:25 AM Innovations in Nuclear Resonance Fluorescence with the Clover Array

Speaker: Dr Samantha Johnson (University of North Carolina at Chapel Hill & TUNL)

Session6-T2.pdf

9:45 AM Collectivity across the nuclear chart

Speaker: Dr Heather Crawford (Lawrence Berkeley National Laboratory)

Session6-T3.pdf

10:05 AM Exploring N=32,34 and 40 and the inverse-impact law

Speaker: Prof. Alexandra Gade (FRIB/MSU)

Session6-T4.pdf

10:25 AM → 10:45 AM Coeee Break

10:45 AM → 12:10 PM Session 7: The unknowns

This session will address open questions and emerging frontiers in nuclear physics, highlighting challenges that define the path forward for the field. Discussions will center on unexplored regions of the nuclear chart, unresolved theoretical questions, and the potential of next-generation facilities and technologies to address these unknowns, ensuring that the exploration of the nucleus continues to advance in the decades to come.

Convener: Dr Filip Kondev (Argonne National Laboratory)

Session7-T0.pdf

10:50 AM Gamma-Ray Spectroscopy at TRIUMF-ISAC: Past, Present, Future

Speaker: Dr Greg Hackman (TRIUMF)

Session7-T1.pdf

11:10 AM Some notes on the last 50 years of nuclear physics and the next 50 years

Speaker: Prof. Alex Brown (FRIB/MSU)

Session7-T2.pdf

11:30 AM On the birth of an alpha particle

Speaker: Prof. Robert Grzywacz (The University of Tennessee, Knoxville)

Session7-T3.pdf

11:50 AM The Rumsfeld Matrix and Weak Binding Speculations

Speaker: Dr Augusto Macchiavelli (Oak Ridge National Laboratory)

Session7-T4.pdf

12:10 PM → 12:40 PM Closing Remarks

Speaker: Prof. Robert V. F. Janssens (The University of North Carolina at Chapel Hill & TUNL)

12:40 PM → 1:40 PM Lunch