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Nuclear Science Division

Nuclear Data Program: From Seaborg to Nuclear Structure and Beyond

The Nuclear Data Program at Lawrence Berkeley National Laboratory (LBNL) and the University of California Berkeley (UCB) is rooted in a tradition of groundbreaking research, tracing its origins to the pioneering discoveries of isotopes by Glenn T. Seaborg and his team. This includes technetium-99m, which remains sought after in modern nuclear medicine with millions of diagnostic procedures performed annually worldwide. During the first 50 years, the nuclear data efforts were primarily focused on decay and neutron capture data, forming a cornerstone of nuclear science. 

Over the last decade, the program has diversified and expanded into actively addressing nuclear data needs for applied areas such as plasma nuclear science, isotope production for space and medical applications, and nuclear energy innovations from fusion to advanced fission systems as well as the fundamental nuclear and astrophysical sciences. Recent highlights include results on isomer populations using laser driven electron beams [1] and providing new and improved nuclear data critical for molten salt chloride reactors, key to next-generation nuclear energy systems [2].

Today, the program’s activities are broader than ever, addressing pressing needs in nonproliferation, national security, and nuclear science applications. For instance, LBNL and UCB researchers are advancing data collection in the nuclear quasicontinuum and refining models to support nuclear-plasma interactions and energy production.

Looking forward, the Nuclear Data Program aims to continue its efforts aligned with the national plan to meet nuclear data needs across basic sciences and applications. This includes a commitment to train the next generation of scientists and engineers, ensuring sustained innovation and expertise. By integrating cutting-edge methodologies with domestic and global collaborations, the program is poised to maintain its leadership in shaping the future of nuclear data efforts.

For more information, visit LBNL’s Nuclear Data and UCB’s Nuclear Data Program .

Figure 1: The GENESIS detector array at LBNL which is used by the Nuclear Data Program to measure neutron induced nuclear data.
  1. Robert E. Jacob et al., Physical Review Letters, accepted for publication (2024). ↩︎
  2. T.S. Nagel et al., Phys. Rev. C  110, 03461 (2024). ↩︎

GRETA Demonstrates Key Performance Parameters

The Gamma-Ray Energy Tracking Array (GRETA) project is advancing quickly towards the Critical Decision 4A (CD-4A) milestone, which marks the completion of the majority of the project scope, and will be followed by delivery of the array to the Facility for Rare Isotope Beams (FRIB) this summer.  

A critical step in the preparation for CD-4A is to demonstrate that all of the key performance parameters (KPPs) defined for the project, which capture the required capabilities of the system, have been achieved.  These included delivery of at least 6 GRETA Quad Detector Modules, and the electronics systems to instrument fully all 30 GRETA Quad Modules which will comprise the complete array.  With the support of the LBNL survey and alignment group, the project has also confirmed that the GRETA mechanical support structures can hold the load of all 30 Quad Modules with the required precision and can be aligned such that the location of all detectors is known at the level of better than 1mm.

Computing performance was also verified in January with the demonstration of the GRETA computing cluster’s capacity to perform “signal decomposition”, or the localization of gamma-ray interactions within a HPGe crystal.  This computationally-expensive calculation was demonstrated at 511,000 signal decompositions per second, exceeding the specified 480,000 for which the array was designed.

Finally, the integrated systems performance was confirmed through measurement of a gamma-ray calibration source with 6 Quad Modules installed in the GRETA array at Building 88 onsite at LBNL.  Pictured in Figure 1, the Quad Modules were installed in a close-packed configuration and fully instrumented with all of the GRETA electronics and support systems.  The system KPP required the  energy resolution to be less than 3.0 keV for the 1.33 MeV transition using a 60Co source – the project achieved a resolution of 2.39 keV, exceeding the required performance.

GRETA is a $58M project funded by the DOE Office of Nuclear Physics and led by the LBNL’s Nuclear Science Division (NSD). The project team that includes staff from NSD, ESNET, and Engineering Division at LBNL, and from Argonne National Laboratory, Oak Ridge National Laboratory and FRIB, are now preparing for the CD-4A review of the project to take place later this Spring.

View inside GRETA frame, 6 Quad modules of GRETA installed in the first configuration for testing.
Figure 1: 6 Quad modules of GRETA installed in the first configuration for testing.

Director’s Corner

February 2025

It has been a busy time for the division since the last newsletter with various research advances, awards, collaboration meetings, and other activities, some of which are featured in this issue of the NSD Newsletter. 

The GRETA project has made steady progress and started to demonstrate its Key Performance Parameters (KPP), a major step towards achieving CD4-A approval for early science planned for this spring. You can find more details on the GRETA progress in this issue of the newsletter.  In November we welcomed 180 scouts to the Lab for the  12th Annual Nuclear Science Day for Scouts and a number of NSD volunteers supported the event. In December, we held our 2nd annual off-site division retreat with close to 120 participants engaging over two days in broad discussions covering NSD science highlights, our collaboration across the division and across Berkeley Lab, career development strategies, outreach engagement, and culture building activities. Following outcomes from the 2023 division pulse survey and last-year’s lab-wide culture survey the division has also rolled out a Community Agreement to support ourselves and each other in building a stronger community culture in the division. You can find more context on this in this issue. 

Since our last Newsletter, there were also a number of other noteworthy developments. We were able to celebrate Raúl Briceño, a faculty scientist in the Nuclear Theory Group who was among the recipients of this year’s Presidential Early Career Award for Scientists and Engineers. The Nuclear Data Group in the Low-Energy Program was elevated to a Program within the Division, recognizing its leading role in the national and international nuclear data communities, and the growth of nuclear data initiatives in basic and applied research. An example for this is the recent Physical Review Letter (PRL) by a collaboration of scientists from the Accelerator Technology & Applied Physics (ATAP) Division and NSD’s Nuclear Data Program. The paper reports on the enhancement of isomer population in bromine isotopes when exciting them using ultra-fast electron beams generated via laser-plasma acceleration at ATAP’s BELLA Center.
Other notable publications since the last newsletter include a  PRL on the definition of jets in semi-inclusive deep-inelastic scattering at the future Electron Ion Collider;  and an Editor’s Suggestion in Physical Review C on nuclear-level effective theory of 𝜇→𝑒 conversion.

Raúl Briceño awarded the Presidential Early Career Award for Scientists and Engineers (PECASE)

Raúl Briceño, a faculty scientist in the Nuclear Sciences Division’s Nuclear Theory Group and an assistant professor of physics at UC Berkeley, is one of three Berkeley Lab scientists to receive the Presidential Early Career Award for Scientists and Engineers (PECASE), the highest honor bestowed by the U.S. government on outstanding scientists and engineers early in their careers.

Element 116 efforts featured in two articles

The recent success of efforts by staff in the Accelerator-Based Low-Energy Program to produce element 116, a critical milestone in the search for element 120, has garnered much attention. An article about the achievement was recently published by the Washington Post (paywalled).

A second article, this one published by APS’s This Week in Physics, presents a brief overview of the search for superheavy elements, inspired by the latest LBNL results.

NSD’s Nuclear Data Group becomes the Nuclear Data Program

The Nuclear Science Division is pleased to announce that the Nuclear Data Group in the Accelerator-Based Low-Energy Program will be reclassified as the  Nuclear Data Program, effective November 1st, 2024. This decision reflects the scientific and financial independence of the nuclear data efforts at LBNL.

The elevation of the Program also serves as recognition of its leading role in the national and international nuclear data communities, and the growth of nuclear data initiatives in basic and applied research. With this change comes the appointment of Prof. Lee Bernstein as the Nuclear Data Program Head and Mathis Wiedeking as his Program Deputy.

The program, with its strong connection to the UC Berkeley Department of Nuclear Engineering, will continue to address the data needs of the basic and applied nuclear science community while training the next generation of nuclear scientists and engineers.