10th Workshop on Nuclear Level Density and Gamma Strength

Session

Breakfast session

18 May 2026, 09:00

Auditorium 1 (Helga Engs Hus)

Conveners

Breakfast session

• Magne Guttormsen (University of Oslo)

Breakfast session

• Artemis Spyrou

Breakfast session

• Johann Isaak

Breakfast session

• Atsushi Tamii

Breakfast session

• Dennis Muecher (Institute for Nuclear Physics, University of Cologne)

38. High Flux Nuclear Science: From Medicine to Space Exploration to High Energy Density Physics

Prof. Lee Bernstein (UC Berkeley/LBNL)

18/05/2026, 09:20

Oral

The short range of the nuclear force has often been used by nuclear physicists to justify ignoring most of the influence of a high energy density plasma (HEDP) environment on neutron induced nuclear reaction dynamics. However, the recent achievement of Lawson’s criterion [1] and the achievement of target gain >1 at the National Ignition Facility (NIF) [2] has for the first time created a...

12. Nuclear Level Densities and Photon Strength Functions for Basic Science and Applications

Paraskevi Dimitriou (International Atomic Energy Agency)

18/05/2026, 09:50

Oral

Nuclear level densities (NLD) and photon strength functions (PSF) are essential input parameters for theoretical calculations and evaluations of nuclear reaction data for basic science and a wide range of nuclear applications.
The IAEA Reference Input Parameter Library (RIPL), released in 2009 [1], provided reliable level‑density and photon‑strength‑function models and recommended values...

7. Isomer Population via the Quasi-Continuum with Laser-Accelerated Electrons

Mathis Wiedeking (Lawrence Berkeley National Laboratory)

18/05/2026, 10:20

Oral

Experiments were performed at the Berkeley Lab Laser Accelerator (BELLA) facility, where $^{81}$Br targets were irradiated using 15 MeV electron beams. The associated bremsstrahlung radiation served as a control for the measurements. The experiments were conducted under a range of spatially and temporally focused and defocused beam conditions, enabling a systematic investigation of their...

10. Average resonance parameters derived from neutron resonances

Milan Krticka (Charles University, Prague)

18/05/2026, 10:40

Oral

Average resonance parameters, particularly the average resonance spacing, derived from experimental neutron-resonance data are essential for many nuclear-physics applications, including testing level-density models and normalizing experimental results. Two widely used compilations are the IAEA RIPL-3 database [1] and Said Mughabghab’s Atlas of Neutron Resonances (latest edition 2018) [2]....

34. Determining the electric or magnetic nature of the low-energy enhancement in nuclei

Sean Liddick (FRIB/MSU)

19/05/2026, 09:00

Oral

The photon strength function (γSF) defines the likelihood of photon emission as a function of photon energy and the properties of the initial and final nuclear states. Of the features present in the γSF, an enhancement in the low-energy region has been observed in some nuclei. Despite two decades of research, the electromagnetic nature of this enhancement remains an open question. This low...

48. Photon Strength Function of $^{90}$Zr from radiative $^{89}$Y(p,$\gamma$) using GRETINA

Dr Kgashane Malatji (University of California Berkeley)

19/05/2026, 09:30

1

Oral

The electromagnetic dipole response of atomic nuclei is fundamental for understanding nuclear structure and reaction dynamics. Measurements of photon strength functions (PSFs) have revealed phenomena such as Low-Energy Enhancement, significantly affecting astrophysical reaction rates relevant to nucleosynthesis.

To investigate the shape of the PSF and the observed excitation modes below...

25. Neutron-capture cross sections for heavy-mass fission fragments constrained with the $\beta$-Oslo method

Adriana Sweet (Lawrence Livermore National Laboratory)

19/05/2026, 10:20

Oral

The upcoming operation of the nuCARIBU facility at ATLAS will enable new measurements of neutron rich La isotopes, which are important both for U.S. stockpile stewardship applications and for understanding the nucleosynthesis of heavy elements in the cosmos. In particular, constraining the $ ^{146} $La(n,$ \gamma $)$ ^{147} $La and $ ^{147} $La(n,$ \gamma $)$ ^{148} $La reactions through...

55. Constraining the $^{95}$Zr(n,$\gamma$) cross section using SONIC at Horus

Dennis Muecher (Institute for Nuclear Physics, University of Cologne)

19/05/2026, 10:40

Oral

The $^{95}$Zr(n,$\gamma$) cross section is crucial for understanding the intermediate neutron capture process (i process), as it directly affects the production and abundance of Molybdenum isotopes. The observed Molybdenum overabundance in presolar grains represents one of the most significant signatures of i-process nucleosynthesis. At the same time, $^{95}$Zr remains a branching point in the...

74. Exploring PDR and IV-GQR Strengths with Inelastic Proton Scattering at the Krakow Cyclotron Centre Bronowice

Agnese Giaz (INFN - Sezione di Milano)

20/05/2026, 09:00

Oral

The experimental campaign carried out at the Krakow Cyclotron Centre Bronowice, aimed at determining the strength of the Pygmy Dipole Resonance (PDR) and the isoscalar Giant Quadrupole Resonance (IS-GQR), will be presented. Both studies were performed using the same experimental setup and based on inelastic proton scattering techniques. A series of measurements focusing on the PDR in stable...

5. Configuration Interaction Shell Model Studies of Photon Strength Functions

Kamila SIEJA

20/05/2026, 09:30

Oral

In this contribution, I will report on recent CI-SM results covering the large-scale evaluation of electric dipole PSF in light and mid-mass nuclei, their applications, as well as first calculations of isoscalar and isovector modes in neutron-rich nuclei, permitting a CI-SM insight into the isospin-mixing of the PDR. If time allows, I will also discuss recent progress of establishing an...

15. Exploring the Pygmy Dipole Resonance across the Sn mass region with the Oslo method

Maria Markova (University of Oslo)

20/05/2026, 10:00

Oral

The pygmy dipole resonance (PDR) is commonly associated with an excess $E1$ strength on top of the low-energy tail of the giant dipole resonance (GDR) close to the neutron-separation energy in stable and unstable heavy nuclei. While its detailed structure, properties, and origin remain a matter of ongoing debates and research, the neutron-skin oscillation picture of this feature still prevails...

21. Threshold-aligned Pygmy Dipole Strength and Its Impact on Astrophysical (n, gamma) and (gamma, n) Rates

Dr Tanmoy Ghosh (Dept. of Physics, Faculty of Science, University of Zagreb)

20/05/2026, 10:20

1

Oral

Accurate neutron-capture and photodisintegration reaction rates within the Hauser-Feshbach statistical framework are strongly governed by the nuclear $\gamma$-ray strength function and the nuclear level density. Uncertainties in these key nuclear inputs propagate directly into Maxwellian-averaged cross sections and constitute one of the dominant sources of uncertainty in modeling the...

59. Study of the K quantum number of pygmy states in $^{154}$Sm

Refilwe Molaeng (School of Physics, University of the Witwatersrand)

20/05/2026, 10:40

Oral

This work investigates the Pygmy Dipole Resonance (PDR) in the deformed $^{154}\mathrm{Sm}$ nucleus. The aim is to determine whether the PDR splits with respect to the K quantum number in a deformed nucleus, as is the case for the GDR. The study uses the $(\vec{\gamma},\vec{\gamma^\prime})$ reaction to excite dipole states at energies ranging from 3.5 MeV to 7.05 MeV, approaching the neutron...

6. Radiative strength functions from the energy-localized Brink-Axel hypothesis

Oliver Gorton (Lawrence Livermore National Laboratory)

21/05/2026, 09:00

Oral

Radiative strength functions (RSFs) model the bulk electromagnetic response of highly-excited nuclei and are critical inputs for statistical reaction codes. In this talk, I present a definition of the RSF that is consistent with Hauser-Feshbach reaction codes and that can be efficiently computed with the shell model by taking advantage of the energy-localized Brink-Axel hypothesis.

63. Direct Neutron Capture Measurements with a Storage Ring

Iris Dillmann

21/05/2026, 09:30

Oral

Neutron capture reactions are fundamental to understanding the synthesis of elements heavier than iron in stellar environments, occurring through the slow (s), intermediate (i), and rapid (r) neutron‑capture processes. While neutron‑capture cross sections along the valley of stability—particularly for stable or long‑lived isotopes—have been extensively studied, direct measurements on...

26. Microscopic Nuclear Level Densities and Giant Dipole Response within Covariant Energy Density Functional Theory

yuan tian (China institute of atomic energy)

21/05/2026, 10:00

Oral

Nuclear level densities (NLDs) and the giant dipole resonance (GDR) encode complementary aspects of nuclear many-body dynamics and provide the microscopic structural input for compound-nucleus reactions. A consistent microscopic description of both quantities within a unified relativistic framework remains essential for understanding their structural origin and predictive power.

In this...

30. Measurements and Modeling of $^{93}$Nb(n,xn$\gamma$)

Keenan Myers

21/05/2026, 10:20

Oral

A good understanding of Neutron-induced reactions on niobium are important for modeling radiation damage in superconducting magnets used in fusion energy systems and for interpreting archival radiochemical data for national security[1][2]. In order to constrain model parameters used in evaluation, correlated measurements of outgoing neutrons and gammas were collected using the Gamma Energy...

65. Fission with PARIS@VAMOS: At the crossroad between nuclear dynamics and nuclear structure

C. Schmitt (Institut Pluridisciplinaire Hubert Curien, France; Institute of Nuclear Physics Polish Academy of Sciences)

22/05/2026, 09:00

Oral

As obvious from the intense experimental and theoretical work done over the past decades, and the still large amount of open questions, nuclear fission is a particularly complex process. A major reason for this is the interference of various aspects, from both reaction dynamics and nuclear structure, which determines the observables that can be measured in the laboratory. The last years showed...

69. Fission cross sections and nuclear level densities

Stephane Hilaire (CEA, DAM, DIF)

22/05/2026, 09:30

Oral

Despite nearly 90 years since its discovery, the fission process remains a challenge for nuclear theories. Three main aspects have to be contemplated: the fission cross sections (probability that a fission occurs), the fission yields (distribution of the fragments resulting from the scission of the fissioning nucleus) and the fission fragments’ decay (responsible in particular of the prompt...

77. Nuclear fission - experiments and modeling

Ali Al-Adili

22/05/2026, 10:00

Oral

This presentation provides an overview of recent experimental advances in nuclear fission research at the NNRC. We begin by summarizing key results from fission yield measurements performed at the Institut Laue Langevin, together with investigations of isomeric yield ratios obtained using the Nuball detector array. These studies contribute to a more detailed understanding of fragment mass...

32. Measurements of Partial Gamma Ray Production Cross-sections from U-238 Inelastic Scattering

Speero Tannous

22/05/2026, 10:20

Oral

Improved measurements of $^{238}U(n,n'\gamma)$ cross-sections are needed to refine nuclear data evaluations used for fast reactors, stockpile stewardship, and nuclear astrophysics. The preliminary results of an experiment to measure neutron inelastic scattering on a natural uranium target will be presented. A 14 MeV deuteron beam was used to create a pulsed broad spectrum neutron beam via...

66. Fission Program at the Oslo Cyclotron Laboratory: Upcoming Setup and Goals

Neeraj Kumar (Norwegian Nuclear Research Centre (NNRC), University of Oslo)

22/05/2026, 10:40

Oral

Nuclear fission remains one of the most complex processes in low-energy nuclear physics, with some open questions spanning both fundamental nuclear structure and applied nuclear technology. To address these challenges, the Oslo Cyclotron Laboratory (OCL) at the University of Oslo is establishing a dedicated fission research program that exploits its unique combination of light-ion beams and...