Ultracold neutrons enable some of the most precise measurements of neutron properties. With energies in the nano-electronvolt range, these neutrons can be trapped in material or magnetic bottles and observed for extended periods. These long observation times allow for highly accurate determinations of fundamental quantities, including the electric dipole moment of the neutron, the neutron...
One of the most important nuclear reactions in astrophysics is the 15O(α,γ)19Ne(p,γ)20Na reaction, which provides a possible breakout pathway from the hot CNO cycle in stars. Studying this reaction directly in the laboratory is challenging, instead, an indirect study using β-decay proton and α decays of 20Mg was recently performed at TRIUMF. The experiment used the Gamma-Ray Infrastructure for...
Motivated by the need for a more comprehensive algebraic structure to calculate coincidence probabilities of a general decay scheme for gamma ray spectroscopy, we model the decay scheme, rather naturally, as a quiver through which we define a decay quiver. The path algebra of quivers is the underlying, more general, algebra for transition matrices that is typically used in modeling decay...
The neutron electric dipole moment (nEDM) is an important property that can reveal additional breaking of fundamental symmetries, such as charge-parity symmetry, which may help explain why the universe is dominated by matter. The TUCAN collaboration is commissioning a next-generation ultracold neutron (UCN) source to deliver higher UCN density to experiments, aiming to improve the statistical...
Nuclear masses are a fundamental observable that give insight into nuclear structure, fundamental interactions, and astrophysics. Multi-Reflection Time of Flight (MR-TOF) mass spectrometers provide high mass separation power in a short amount of time by bouncing ions between electrostatic mirrors. This increases the flight path of trapped ions allowing ions with the same energies but different...
The unexpectedly large charge radius of the doubly magic nucleus ${}^{52}$Ca, with the new neutron magic number $N=32$, has puzzled theoretical studies, as this trend differs from a decrease in charge radius observed for closed-shell isotopes ${}^{40,48}$Ca. Only the Hartree-Fock-Bogolyubov calculation with the Fayans energy density function was able to reproduce this experimental result. On...
AI is everywhere, but a theoretical understanding of AI behaviour is still lacking. In this talk I will show how high-energy physics, in particular our well-understood data structures, can help open the black box of AI. Closing the circle, a better understanding of AI will help us use AI to better understand the physics of our universe.
At Belle II, $B$ mesons are produced in pairs nearly at rest. The Full Event Interpretation (FEI), a machine-learning based background-suppression method, reconstructs one of the $B$ mesons in a well-known decay mode (the tag side). The remaining particles in the event are then used to reconstruct the signal $B$ meson.
The Semileptonic FEI uses a hierarchical decay-chain reconstruction in...
The MOLLER experiment aims to constrain fundamental parameters in the Standard Model by measuring the parity-violating asymmetry A$_{\rm PV}$ induced by the interference between electromagnetic and weak neutral current amplitudes. MOLLER will utilize polarized Møller scattering at Jefferson Lab to measure a highly precise 0.8 part per billion (ppb) uncertainty on the predicted 33 ppb A$_{\rm...
Supernova (SN) localization from water-Cherenkov neutrino detectors is critical for capturing early optical observations of the next galactic SN, as neutrinos are the earliest observables arriving well before shock breakout. SN neutrino bursts detected by Super-Kamiokande (SK) produce thousands of PMT time-charge (TQ) signals which contain directional information. Our current direction...
Astrophysical neutrinos at the TeV scale would open a new observational window into currently obscured and inaccessible extreme environments, such as the centre of other galaxies. Detecting them poses significant challenges due to their low rate and weak interactions with matter. The Pacific Ocean Neutrino Experiment (P-ONE) addresses this problem by instrumenting a large volume of water at a...
The detection of high-energy cosmic neutrinos by the IceCube and KM3NeT collaborations has raised questions of what astrophysical processes are creating these particles. In order to answer this question, additional large volume neutrino detectors must be constructed to offer full sky sensitivity to neutrino flux. The Pacific Ocean Neutrino Experiment (P-ONE) is a future underwater neutrino...
The ATLAS detector relies on its liquid-argon (LAr) calorimeter to measure the energies of electrons and photons produced in proton–proton collisions at the LHC. After the high-luminosity upgrade of the LHC, the calorimeter will face substantially increased background activity from many overlapping signals produced in nearby bunch crossings, complicating real-time energy reconstruction. To...
Electroweak production of a Z boson in association with two jets (EW Zjj) provides a clean way of probing vector boson fusion (VBF) and serves as a sensitive test of electroweak couplings within the Standard Model at high energies. Using the ATLAS detector at the Large Hadron Collider, this analysis aims to measure differential cross-sections of key observables in the dilepton channel and to...
The Higgs self-coupling, as related to the shape of the Higgs potential, is central to several fundamental questions, such as the dynamics of the early universe, its expansion and cooling, and the origin of baryon asymmetry. By analyzing di-higgs events that occur during proton-proton collisions in the ATLAS experiment, observed bounds have been placed on this self-coupling value, but remain...
The Standard Model (SM) predicts pair production of the Higgs boson, but it has not yet been observed. The physics involved in the creation of Higgs pairs can address numerous open questions in the SM.
There are several searches for Higgs pairs at the ATLAS detector, where they are formed primarily through gluon-gluon fusion (ggF), and the largest decay channel is to b-quark jets. Thus,...
The long-lived γ-ray isotopes observed in core-collapse supernovae remnants are direct signatures of the nucleosynthesis processes that occurred during the explosion. However, interpreting these signatures to understand the explosion dynamics requires precise nuclear physics input. Recent sensitivity studies have identified the ¹³N(α,p)¹⁶O reaction as a major nuclear uncertainty affecting the...
Mass spectrometry plays an important role in many fields of physics research such as nuclear astrophysics, nuclear structure, and fundamental symmetries. Precise knowledge of masses is critical to these studies. For example, a relative mass precision of ≤10^-8 is required to probe the Standard Model and beyond. This level of precision with radioactive species has been achieved only with...
The FrPNC collaboration is working toward a campaign of atomic parity non-conservation (APNC) measurements in francium to study the weak nuclear force. Weak interactions between atomic electrons and nucleons make it possible for electric dipole (E1) transitions to occur between atomic S states. As the heaviest alkali atom, Fr has a higher sensitivity to APNC because the effect scales with...
A muon bound in the 1S state of a hydrogen-like ion can decay into an electron and a pair of neutrinos. For small nuclear charge Z, Überall (1960) predicted a suppression of the total rate relative to the free-muon width, 1−Γ/Γ0≃(αZ)^2/2, α≃1/137. The first all-orders numerical calculation in αZ (Watanabe et al., 1993) reported for oxygen (Z=8) Γ/Γ0=0.994, in tension with Überall’s analytic...
Exploring neutron-rich nuclei near the drip line with significant neutron/proton asymmetry exposes exotic phenomena like the existence of a neutron halo or skin and (dis)appearance of existing magic numbers. Nuclear halos result from the spatial distribution of outermost neutrons, causing a low-density extende. A systematic study of the point proton radii (root mean square radii of the density...
Cd isotopes, particularly $^{110,112}$Cd, have long been considered the best examples of nuclei with vibrational behaviour. However, recent studies challenge this interpretation, suggesting that Cd isotopes possess characteristics of multiple shape coexistence. To further investigate this issue, a series of $\beta$-decay experiments were conducted to improve the spectroscopic information on...
The intruder bands in the mid-shell Sn isotopes, built on the proton 2p-2h excitation across the $Z = 50$ shell gap, are well-known examples of shape coexistence, where more than one shapes appear within the same nucleus. Spectroscopic signatures for shape coexistence include enhanced $E0$ transitions between the $0^+$ band heads. However, until now, lifetime information for the $0^+$ states...
Generalized Parton Distributions (GPDs) are a huge advancement in our understanding of hadronic structure and non-perturbative QCD. To study GPDs, one may use the Deep Exclusive Meson Production (DEMP) reaction. The PionLT experiment in Jefferson Lab Hall C measures the DEMP reaction, but to access GPD information we must perform a LT separation on the data. An LT separation divides the...
Hadronic physics aims to understand the contribution and dynamics of quarks and gluons in the formation of hadrons. Quantum Chromodynamics predicts a number of states, including those having gluonic degrees of freedom called hybrids, but only a few have been established experimentally. The GlueX experiment at Jefferson Lab, USA, utilizes a linearly polarized photon beam of 8-9 GeV and a large...
One of the central challenges in modern physics is to unravel hadronic structure, as the strongly coupled, non-perturbative nature of QCD at low energies makes it difficult to derive the observed properties of hadrons from their underlying quarks and gluons. The pion ($\pi$-meson) is the lightest quark system, and its properties are deeply linked to our understanding of how quarks are confined...
The principal goal of the GlueX experiment at the Thomas Jefferson National Accelerator Facility is to search for
non-q ¯q mesons, a construction not allowed by the simple quark model but predicted by Quantum Chromodynamics.
Specifically, hybrid mesons, which result from the addition of a gluonic field with exotic states and are pictured as a q¯qg
state, will be accessed using a 8.2-8.8 GeV...
The search for neutrinoless double-beta decay ($0\nu\beta\beta$) stands among the most promising avenues for uncovering new physics. An observation would confirm Majorana neutrinos, establish lepton-number violation, and potentially reveal the absolute neutrino mass scale. As next-generation experiments propose to push half-life sensitivities up to two orders of magnitude beyond previous...
Silicon photomultipliers (SiPMs) are single-photon-sensitive devices under consideration for light sensing in noble liquid detectors. One of the experiments considering SiPMs is the neutrinoless double beta decay experiment nEXO. nEXO plans to search for this decay with 5 tonnes of liquid xenon enriched in the isotope Xe-136 over a lifetime of 10 years. SiPMs will be placed inside the liquid...
Neutrinoless double beta decay ($0\nu\beta\beta$) is a hypothetical nuclear process in which two neutrons in a nucleus transform into two protons and two electrons without emitting electron antineutrinos. Its observation would demonstrate lepton number violation in weak processes and confirm that neutrinos are Majorana particles. Next-generation $0\nu\beta\beta$ searches using candidate...
A global program of experiments has worked towards characterizing neutrino oscillation over the past few decades. However, important parameters remain to be measured, and mysteries remain to be elucidated. Current and upcoming experiments are targeting the open questions and probing the consistency of the neutrino oscillation paradigm. Likewise, the liquid argon (LAr) time-projection chamber...
The SNO+ experiment is a kilo tonne-scale liquid scintillator neutrino detector located 2 km underground at SNOLAB in Sudbury, Ontario. Within its broad physics program, SNO+ detects anti-neutrinos through an inverse beta decay (IBD) reaction, producing a characteristic delayed-coincidence signal that can be easily separated from most backgrounds. This allows SNO+ to make two key...
The SNO+ experiment is a multi-phase, kilotonne-scale neutrino detector located 2km underground at SNOLAB in Sudbury, Ontario. SNO+ has an extensive physics program, where the primary objective is a search for neutrinoless double beta decay (0$\nu$$\beta$$\beta$) in $^{130}$Te. To achieve the physics goals, it is essential to have a thorough understanding and calibration of the detector...
Neutrino telescopes are large volume detectors $(\sim$ $1$ $km^3)$ embedded in optically transparent media that observe the secondary particles produced when neutrinos —ranging in energy from GeV to TeV— interact in the medium. These experiments rely on detailed Monte Carlo simulations to interpret their data, yet events at TeV energies and above produce extensive hadronic and electromagnetic...
Now famous as quantum computers, ion traps were already recognized (with the 1989 Nobel Prize) as superior instruments for precision measurements, made possible by long-term observation of their stored quarry.
The use of ion traps for measuring nuclear binding energies at on-line radioactive beam facilities (first CERN-ISOLDE, later TRIUMF-ISAC) has now brought improved topographical...
A new array of Si(Li) detectors is under development for conversion electron spectroscopy in combination with the GRIFFIN decay spectrometer at TRIUMF-ISAC. Internal conversion coefficients play a crucial role in studying electromagnetic transitions in nuclei as they assist in the assignment of spin and parity of excited nuclear states. In addition, the direct observation of L=0, E0,...
This presentation will show ongoing R&D of the new ultra cold neutron detectors. These detectors, filled with He3 at 15 mbar and CF4 to atmospheric pressure, detects neutrons via capture on He3. The resulting proton and triton deposit energy in the CF4, producing scintillation light. These detectors will be used to measure the neutron electric dipole moment (nEDM) by TRIUMF Ultracold Advanced...
Have you ever wondered how all the elements we find here on Earth and in the universe were created? Nearly all naturally occurring elements are produced via nuclear reactions in the interiors of the stars. Half of the elements heavier than iron are synthesized in the slow neutron capture process$~$($s$-process), which occurs mainly in two astrophysical sites: asymptotic giant branch$~$(AGB)...
With the technical complexity required by ongoing dark matter direct detection experiments, as well as requiring more refined background rejection techniques, some direct detection experiments have the ability to investigate neutrinos as well. One such detector in recent years involves the liquid argon based DEAP-3600 experiment. The detector assembly allows for nearly 3600 kg of liquid argon...
Liquid argon has proven to be a powerful medium for detecting GeV‑scale dark matter, as demonstrated by the DEAP‑3600 and DarkSide‑50 experiments. Building on these successes, DarkSide‑20k is now under construction at LNGS as the first flagship detector of the Global Argon Dark Matter Collaboration. With a 50‑tonne ultra‑pure argon target and exceptionally low backgrounds, DarkSide‑20k, in...
The Global Argon Dark Matter Collaboration (GADMC), formed to unite liquid argon–based dark matter experiments, is currently constructing its next-generation experiment DarkSide-20k. Located at the Laboratori Nazionali del Gran Sasso (LNGS), DarkSide-20k builds upon the success of previous argon experiments, including its predecessor, DarkSide-50, to continue the search for weakly interacting...
The Scintillating Bubble Chamber (SBC) collaboration combines historic bubble chamber technologies with the scintillation properties of liquid nobles to create a detector uniquely suited to low threshold rare event searches. The collaboration has built two nearly identical assemblies; SBC-LAr10 is being used for calibration studies at Fermilab and planned future coherent elastic...
The latest results from the DEAP-3600 experiment in the search for dark matter will be presented. DEAP-3600 is a direct detection experiment that uses 3.3 tonnes of liquid argon as its target material. Located over 2 km underground at SNOLAB in Sudbury, Canada, the detector is designed to observe scintillation light from nuclear recoils induced by dark matter interactions. Pulse-shape...
The sudden onset of deformation in $A\approx100$ nuclei at $N=60$ has been described as a ground-state shape transition that has raised a lot of interest over the years from an experimental and theoretical point of view. This transition is most pronounced in the Zr and Sr isotopic chains where the low-energy excited-state structure shows significant signs of deformation developing at $N=60$,...
One of the long standing questions in the standard model of particle physics is the origin of nucleon mass, spin, and the charge and density spatial distributions within. In the theory of the strong interaction, the structure of the nucleon is described by form factors which can be accessed through hard exclusive meson production. The main focus of this study is to measure the form factor of...
Type I X-ray bursts are among the most frequent thermonuclear explosions we can observe, and can reveal important properties of accreting neutron star systems. Understanding their light curves requires detailed knowledge of the nuclear reactions that enable the transition from the hot CNO cycle towards explosive burning and the rp process. One such key breakout reaction is the 14O(α,p)17F...
A sudden ground-state shape transition is known to occur sharply at $N=60$, accompanied by equally dramatic changes in the low-energy spectra of the nuclei with A$\approx\!$100. Detailed spectroscopic data on the $\gamma$ decay of $^{100}$Zr are essential for understanding this phase transition and the emergence of shape coexistence, predicted by recent Monte Carlo Shell Model (MCSM)...
As nuclei get richer in neutrons, the Q-value for beta-decay gets larger while the neutron separation energy decreases. Consequently, for large enough N/Z ratios, the daughter nucleus can decay by emitting one to several neutrons. Directly studying states above the neutron separation energy is an experimental challenge as it requires neutron detectors that have a good energy resolution while...
