Conveners
Nuclear and Particle Physics
- Michael Schmidt (UNSW Sydney)
Nuclear and Particle Physics
- Navneet Krishnan (Australian National University)
Nuclear and Particle Physics
- David Cortie
The existence of two-ฮณ-phonon excited states in rare-earth nuclei remains a contentious issue in nuclear structure. While examples of single-phonon ฮณ-vibrational states are prevalent in even-even deformed nuclei, identifying two-phonon excitations is challenging due to strength fragmentation and competing non-collective states. Although two-phonon states are predicted by the collective model...
Nuclear magnetic resonance exploits the delicate sensitivity of nuclear spin to characterise the local dynamics and structure of the surrounding chemical and magnetic environment inside materials. ฮฒ-NMR is an extension of this technique, similar to muon spectroscopy, which relies on the detection of anisotropic beta emission produced by a polarised radioactive isotope such as โธLi. This allows...
The calcium ($Z = 20$) nuclides have long been considered as โtextbookโ shell-model nuclei, with established doubly magic isotopes at $N = 20,~28$ and proposed shell gaps emerging at $N = 32,~34$. Despite this, a growing body of evidence suggests that the shell model requires deeper investigation in this region. In $^{48}$Ca, a reduction of the $f_{7/2}$ strength across the $N = 28$ shell gap...
A leading challenge in nuclear-structure research is to experimentally establish regions of oblate and triaxial deformation. Such a phenomenon is not only interesting from a fundamental structure perspective, but could also provide vital understanding and constraints of the flow of r-process nucleosynthesis in the vicinity of the $N=82$ shell closure [1]. The very neutron-rich Mo-Ru-Pd...
Comparison between large-basis shell-model calculations and experimental data gives insights into the emergence of nuclear collectivity. One experimental observable that can be examined is the $g$ factor, which gives a sensitive test of the proton versus neutron character of the nuclear states. There are extensive data on the first-excited states of even-even nuclei measured by the...
Simulations of radiation and particle transport via Monte Carlo (MC) codes are integral to the design and safety of nuclear reactors, medical radiation systems and detector systems. A lesser known application of these simulations is in defence and national security, where such tools can provide crucial information for threat assessments and analysis of real world detector readings. These...
Sub-GeV mass dark matter has seen significant theoretical and experimental interest in recent years, with many proposed and upcoming direct detection experiments targeting this regime. In this talk, I will present new constraints on hadronically-interacting dark matter that arise from one-loop interactions with photons and electrons during big bang nucleosynthesis, as well as from rare meson...
There is growing interest in the application of quantum information theory concepts to particle physics model-building. Recentย research has established that the extremization of entanglement in particle scattering provides a natural way to realise interesting theoretical structure, both within and without the Standard Model. The success of these entanglement studies begs the question: can...
Parity nonconservation (PNC) in atoms is a tiny weak interaction effect,
arising largely from Z-boson exchange between atomic electrons and neutrons. This has been a rich area of study for the past few decades with the weak charge measured with up to a fraction of a percent precision, and the nuclear anapole moment experimentally observed once, with an uncertainty approaching 10%. Of recent...
The electromagnetic form factor, $F_\pi(Q^2)$, of the pion describes how quarks are distributed inside the pion and is of considerable phenomenological interest. However, $F_\pi(Q^2)$ at large values of momentum transfer, $Q^2$, has proven difficult to measure experimentally. This motivates numerical approaches to its calculations, such as lattice QCD. Though Lattice QCD calculations of...
Neutron-rich nuclei around A$\sim$100 present intriguing cases in nuclear structure due to their significant deformation and complex shapes, including predicted triaxiality as well as rare oblate-deformed ground states. These features pose challenges for theoretical models, especially in describing the abrupt shape transitions observed between N = 58 and 60. Even-even nuclei in this region...
Accelerator storage rings for light sources and colliders are highly sensitive to magnet misalignments and field errors. These imperfections distort the orbit, which negatively impact the brightness or luminosity. Precise orbit correction plays a vital role in optimising the performance of next generation lepton accelerators.
CERNโs proposed e+/e- Future Circular Collider (FCC-ee) is a...
Dark matter detectors, in particular those based on dielectric materials, are among the best tools for probing light dark matter. In the coming years detectors of this type will become sensitive to solar neutrino scattering. For dark matter scattering at very low recoil energies, collective excitations of the electrons in the solid become important. In this talk I'll share some new results...
SABRE is an international collaboration that will operate similar particle detectors in the Northern (SABRE North) and Southern Hemispheres (SABRE South). This innovative approach aims to distinguish potential dark matter signals from seasonal backgrounds: a pioneering strategy only feasible with a Southern Hemisphere experiment. SABRE South is located at the Stawell Underground Physics...
The interplay between theoretical cosmology and particle physics seeks to answer fundamental questions related to our Universeโs formation and constituents. Today, it is well established that dark matter (DM) accounts for nearly 30% of the cosmic energy budget [1]. Several particle physics models of DM are being extensively studied; however, there has yet to be any luck with its detection. The...
Baryon number is conserved in the Standard Model (SM). Its violation is one of the most compelling phenomena predicted by physics beyond the SM. I will discuss the theoretical description of baryon-number-violating nucleon decays within the framework of effective field theory, which can be used to interpret existing data of Super-Kamiokande and upcoming data from the next-generation neutrino...
Recent observations by the CMS and ATLAS experiments at the LHC have reported anomalies in the production of tau-lepton and photon pairs over expected background at an invariant mass of ~95 GeV. Taken with an older result from LEP data showing a similar anomaly in the production of b-quark pairs, these results raise the possibility of an as-yet unknown resonance at 95 GeV causing each of these...
XLZD is a future dark-matter direct detection experiment that will use a liquid Xenon (LXe) based Time Projection Chamber (TPC) to search primarily for Weakly Interacting Massive Particles (WIMPs), with sensitivity all the way to the neutrino-fog for WIMP candidates with mass above about 3 GeV/c^2. The typical channel used to search for these particles is through their recoil on the nuclei of...
Sub-GeV mass dark matter has seen significant theoretical and experimental interest in recent years, with many proposed and upcoming direct detection experiments targeting this regime. In this talk, I will present new constraints on hadronically-interacting dark matter that arise from one-loop interactions with photons and electrons during big bang nucleosynthesis, as well as from rare meson...
