Nuclear Physics

Nuclear physics investigates the properties, structure and reactions of atomic nuclei, the dense assemblies of protons and neutrons bound by the strong nuclear force. Central themes include the arrangement of nucleons into shell structures, the emergence of collective phenomena such as deformation and rotation, and the competition between compound-nucleus formation and fission in heavy-ion collisions. Studies extend from stable, naturally occurring isotopes along the “valley of stability” to exotic, short-lived nuclei at the proton and neutron driplines that illuminate astrophysical processes and the limits of nuclear binding. Experiments employ accelerators, separators and advanced detector arrays to measure masses, decay modes, cross sections and transition strengths, while theory blends mean-field approaches, configuration interaction and beyond-mean-field methods to model observed spectra. Applications span nuclear energy, medicine and materials analysis, and underpin our understanding of nucleosynthesis in stars. Ongoing advances in rare-isotope facilities and computational many-body techniques promise a comprehensive mapping of the nuclear landscape and deeper insight into the fundamental forces at play.

Research from Nature Portfolio

Recent analyses of near-barrier collisions between medium-mass and heavy nuclei have revealed an unexpectedly rich spectrum of mass and charge partitions prior to capture, indicating that multinucleon transfer channels profoundly influence the probability of forming superheavy compound systems. Cutting-edge imaging of uranium-uranium and uranium-lead collisions at ultrarelativistic energies has enabled the first “snapshots” of instantaneous nuclear shapes, showing pronounced deformations and slight departures from axial symmetry that are imprinted on the collective expansion of the quark–gluon plasma. In parallel, systematic surveys of electric quadrupole transition rates across the nuclear chart have uncovered new signatures of “regular” nuclei, using patterns in measured E2 strengths to propose previously unrecognised candidates for robust, orderly collective behaviour beyond established shell closures.

Research from all publishers

High-precision measurements of proton–proton elastic scattering at the LHC have determined the total cross section and the ρ-parameter at √s=13 TeV by exploiting the Coulomb–nuclear interference region, refining our knowledge of the forward scattering amplitude and informing cosmic-ray models. Ultrarelativistic heavy-ion data at the LHC have been used to extract the neutron-skin thickness of ²⁰⁸Pb via detailed hydrodynamic analyses of collective flow, establishing a novel link between ground-state nuclear structure and quark–gluon plasma observables. In turn, dedicated studies of lead–lead collisions have quantified the speed of sound in the high-temperature medium, confirming lattice QCD predictions for the quark–gluon equation of state by correlating charged-particle spectra with theoretical models of relativistic expansion.

Nuclear Physics publication trend

The graph below shows the total number of articles in nuclear physics across all publications each year (not limited to Nature Index journals).

Technical terms

Nuclear shell closure: A configuration in which proton or neutron energy levels form complete shells, yielding extra stability at “magic” numbers.

Proton/neutron dripline: The boundary in the nuclear chart beyond which adding another proton or neutron produces an unbound system that immediately decays.

Quasi-fission: A rapid two-body re-separation process in heavy-ion collisions occurring before full compound-nucleus equilibration.

Neutron-skin thickness: The difference between neutron and proton root-mean-square radii in a nucleus, reflecting neutron-rich surface layers.

Equation of state: The relation between pressure, energy density and temperature of nuclear or quark–gluon matter, determining its expansion dynamics.

Collective flow: Anisotropic hydrodynamic expansion pattern of matter in heavy-ion collisions, driven by initial spatial asymmetries and pressure gradients.

References

1. Introduction.
2. Colliding heavy nuclei take multiple identities on the path to fusion. Nature Communications (2023).
3. Imaging shapes of atomic nuclei in high-energy nuclear collisions. Nature (2024).
4. New pattern in regular nuclei based on their experimental quadrupole transition rates and some new candidates. Scientific Reports (2023).
5. Measurement of the total cross section and ρ-parameter from elastic scattering in pp collisions at s=13 TeV with the ATLAS detector. European Physical Journal C (2023).
6. Determination of the Neutron Skin of Pb208 from Ultrarelativistic Nuclear Collisions. Physical Review Letters (2023).
7. Extracting the speed of sound in quark–gluon plasma with ultrarelativistic lead–lead collisions at the LHC. Reports on Progress in Physics (2024).