Five members of the FRIB user community were named 2019 American Physical Society (APS) Fellows: Daniel Bazin, Mahananda Dasgupta, Jutta Escher, Rituparna Kanungo, and Sofia Quaglioni.

Fellows are selected by their peers for their outstanding contributions to physics. Each year, the number of APS fellows elected is no more than one half of one percent of the membership.

APS is a nonprofit membership organization that works to advance and spread knowledge of physics via publications, meetings, activities, and more.

DANIEL BAZIN

Daniel Bazin is an adjunct professor in the Department of Physics and Astronomy at Michigan State University and a senior physicist at FRIB.

Bazin was elected by APS for “groundbreaking work developing nuclear reaction mechanisms for the study of rare isotopes, and for the conception and application of innovative technology to enable novel experiments.”

Bazin’s research focuses on understanding the mechanisms underlying the nuclear reactions that are used to study rare isotopes. Nuclear reactions can be used to extract the properties of nuclei, but they have to be modeled accurately in order to obtain reliable quantitative results. His experimental program aims at validating the reaction models using specially designed experiments. Another part of his research involves designing and using novel experimental methods and technology to push the limits of observation on rare isotopes. Low-energy reactions performed on rare isotopes are challenging because reaction products have very low energy and can emerge from a solid target only if it is extremely thin. This reduces the chances that a nuclear reaction can occur and limits the observation of nuclear phenomena. Developing an “active target,” which is a target and a detector at the same time, can mitigate this limitation.

Bazin earned his PhD in nuclear physics at the University of Caen in France. Previously, he was a tenured research physicist at the French National Center for Scientific Research at the Great Heavy-Ions National Accelerator in France. Bazin is a member of the American Physical Society and an editor at Nature’s Scientific Reports.

“I feel very honored,” said Bazin of being elected as an APS fellow. “It means that my colleagues acknowledge the work I have done so far as significant and having an impact in the field of nuclear physics.”

MAHANANDA DASGUPTA

Photo credit: Michael J. Hood

Mahananda Dasgupta is a professor and experimental physicist at the Heavy Ion Accelerator Facility in the Department of Nuclear Physics of the Australian National University.

Dasgupta was elected by APS for "advancing the understanding of nuclear fusion through precision measurements, highlighting the role of quantum superpositions and demonstrating the suppression of fusion for weakly-bound nuclei.”

Fusion of heavy nuclei involves a massive dynamical rearrangement of quantum systems with many degrees of freedom as two separate nuclei merge to become a single nucleus. The approaching nuclei are in a coherent superposition of the quantum states of the two separated nuclei, which effectively replaces the single fusion barrier by a multitude of barriers. The latter, demonstrated experimentally through precision measurements of fusion cross sections, not only affect how nuclei come together, but also how they can come apart prior to fusion. The precision measurements also provide a measure of the average fusion barrier, which proved critical in demonstrating that the complete fusion of weakly bound alpha-cluster nuclei is suppressed by 30 percent compared to more tightly bound nuclei.

Dasgupta earned her PhD from the Tata Institute of Fundamental Research in Bombay (now Mumbai), India. She is a Fellow of the Australian Academy of Science, and was awarded a Queen Elizabeth II Fellowship by the Australian Research Council, and an Australian Laureate Fellowship from the Australian Research Council.

“I felt honored and absolutely delighted to learn that my contributions to the field were recognized by Fellows of APS,” said Dasgupta. “It is an affirmation of the impact of our work and its international visibility. It also feels like a celebration of achievements – not just mine, but my colleagues, post-docs and the many graduate and undergraduate students whom I have worked with and who have enriched my research and my life.”

JUTTA ESCHER

Jutta Escher is a physicist in the Physical and Life Sciences (PLS) Directorate at Lawrence Livermore National Laboratory (LLNL).

Escher was elected by APS for “developing the theoretical framework required to validate the surrogate reaction method for neutron-induced reactions and for leading the applications of these methods to address important questions in nuclear astrophysics and stewardship science.”

Escher’s research involves indirect measurements of neutron-induced reactions. These measurements are important for many applications, as direct methods can often not be used for very short-lived target nuclei. To extract the relevant information from a “surrogate” charged-particle experiment, one needs a detailed description of the reaction mechanism, and a close collaboration between theory and experiment. The work Escher has been doing with her colleagues demonstrates the approach and paves the way for future applications in inverse-kinematics experiments at FRIB.

Escher earned her PhD in physics from Louisiana State University. She was a postdoctoral researcher at the Hebrew University in Jerusalem and at TRIUMF in Vancouver, Canada. She has been a staff member at LLNL since 2002. Escher has (co)organized a number of scientific meetings and is the founding organizer of the international workshop series “Compound-Nuclear Reactions and Related Topics.”

“I felt very honored when I learned that I had been elected APS Fellow, and I am very grateful for the opportunity to work on challenging problems that are recognized and valued by our community,” said Escher. “An APS Fellowship shows that our community recognizes a development as important and the advances made as significant. This honor is a recognition of not only my contributions, but also of the work of my collaborators, and it serves as a strong motivation to continue research along these lines.”

RITUPARNA KANUNGO

Rituparna Kanungo is a professor of physics at Saint Mary’s University, Halifax, and an affiliate scientist at TRIUMF in Vancouver, Canada.

Kanungo was elected by APS for “seminal studies of weakly bound nuclei that have challenged our understanding of the nuclear many-body system and for the development of innovative experimental techniques and approaches used in measurements with rare isotope beams.”

As the neutron number in an element increases, the last one or two neutron(s) suddenly become very weakly bound. In such conditions, exotic forms of nuclei appear, deviating from the conventional expectation. The weakly bound neutrons tend to become located far away from the rest of the nucleus, thereby forming a large neutron halo on the nuclear surface. In some other isotopes, a neutron skin develops. Kanungo’s experiments have found and characterized these exotic halos and skin by measuring the nuclear size, i.e. radii, momentum distribution and in some cases, their excitation modes.

Kanungo earned her PhD from the Saha Institute of Nuclear Physics at the University of Calcutta in India. She is currently serving as the president of the Canadian Institute of Nuclear Physics, the director of international affairs in the Board of Directors of the Canadian Association of Physicists (CAP), and the chair of the Canadian International Union of Pure and Applied Physics liaison committee.

"It was a truly rewarding moment of pleasant surprise, one which instantly made me thankful to a multitude of people around me: my collaborators, our research centers, our research community at large, my supervisors and mentors, our funding agencies, and my family members,” said Kanungo. "I am deeply honored to have been chosen to receive this prestigious recognition from the APS, which I would like to share with all my students, post-doctoral fellows, and collaborators. I am immensely thankful to my peers for valuing my contributions.”

SOFIA QUAGLIONI

Sofia Quaglioni is the deputy group leader for Nuclear Data and Theory group at Lawrence Livermore National Laboratory (LLNL).

Quaglioni was elected by APS for “contributions to unifying theories for the structure and dynamics of light nuclei by elucidating the role of the continuum in weakly bound nuclei, and the inclusion of three-body final states and three-nucleon interactions within reaction dynamics.”

Working in a team that includes colleagues at LLNL and the University of Trento in Italy, Quaglioni is developing an unconventional quantum computing protocol that will enable successful quantum simulations of nuclear dynamics on quantum processors. If successful, the work will give proof of the untapped utility of quantum computing with current day hardware and help obtain exact solutions of nuclear processes that span the entire chart of nuclides.

Quaglioni earned her PhD in physics from the University of Trento and was a postdoctoral fellow at the University of Arizona. She has served on the National Advisory Committee of the Institute for Nuclear Theory and on the Theory User Group Executive Committee of FRIB. She is presently a member of the joint U.S. Department of Energy/National Science Foundation Nuclear Science Advisory Committee. Quaglioni is also a member of the multi-institutional DOE Topical Collaboration on Double Beta Decay and Fundamental Symmetries.

“It is heartwarming being recognized by your peers for the work you have done over the years,” said Quaglioni. “I am also very grateful to my colleagues and past mentors for their efforts in nominating me for this special honor and for all the opportunities I have been afforded over the years at LLNL and within the broader nuclear science community⁠—which have made this possible.”