Conveners
Fundamental Symmetries and Interactions
- Pierre DELAHAYE (GANIL)
Fundamental Symmetries and Interactions: 2
- There are no conveners in this block
Neutron dark decays have been suggested as a solution to the discrepancy between bottle and beam experiments, providing a dark matter candidate that can be searched for in halo nuclei. The free neutron in the final state following the decay of $^{6}$He into $^{4}$He + n + χ provides an exceptionally clean detection signature when combined with a high efficiency neutron detector. We will report...
The world’s leading measurement of the neutron’s electric dipole moment (EDM) is currently ongoing at the Paul Scherrer Institute (PSI): the n2EDM experiment. n2EDM will deliver, at minimum, an order of magnitude better sensitivity as compared to current limits on the neutron EDM. This increased sensitivity on the neutron EDM will provide stringent constraints on time-reversal violating...
The TRIUMF UltraCold Advanced Neutron (TUCAN) collaboration is completing a new ultracold neutron (UCN) source, which aims to be the world's strongest, with an instantaneous production rate of 1.6 × 10⁷ UCN/s.
High-energy neutrons are produced by a spallation target irradiated by a proton beam from the TRIUMF cyclotron, then moderated in heavy water and liquid deuterium. UCNs are subsequently...
The Standard Model of particle physics is a widely accepted and well-established theory that is able to describe electromagnetic, weak, and strong interactions using a common framework. However, phenomena such as masses of the neutrinos, the matter–antimatter asymmetry and the nature of dark matter and dark energy remain unexplained. At the Paul Scherrer Institut (PSI) we are setting up an...
Around us we see an universe filled with galaxies, stars and planets like ours. But when we look back to the Big Bang and the processes that created the matter in it, at first we observe that there should have been created the same amount of matter and antimatter, thus the universe would be empty or different than it is. Sakharov suggested several conditions to explain the matter-antimatter...
On Behalf of ALPHA Collaboration
CPT symmetry is a fundamental principle in the Standard Model of particle physics. Antihydrogen, the simplest atom of antimatter, is ideal for testing CPT invariance by comparing its properties with those, very well known, of hydrogen. The ALPHA experiment at CERN focuses on producing, confining, and studying antihydrogen. Antihydrogen is synthesized by...
On behalf of the GBAR collaboration
The properties of antimatter with respect to matter have been explored with utmost accuracy, except for its gravitational behaviour. The GBAR experiment, based at CERN’s AD/ELENA facility, is designed to investigate the weak equivalence principle by measuring the free-fall acceleration of antihydrogen in the Earth gravitational field.
To achieve...
The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for 0νββ decay that has successfully reached the one-tonne mass scale. The detector, located at the LNGS in Italy, consists of an array of 988 TeO$_2$ crystals arranged in a compact cylindrical structure of 19 towers. CUORE has been collecting data continuously at ~10 mK since 2017,...
The observation of neutrinoless double beta (0$\nu\beta\beta$) decay would have profound implications on the field of neutrino physics, giving key insights into multiple questions simultaneously. It would prove the existence of a lepton number violating process, determining if neutrinos are Majorana particles as well as constraining the overall mass hierarchy and the absolute mass scale of the...
The existence of the three flavours of neutrinos, electron, muon and tau neutrino, predicted by the Standard Model of particle physics has been experimentally proven decades ago. Contrary to the Standard Model however, neutrino oscillation experiments [1] have shown that they are massive particles, making neutrino mass measurements a gateway to physics beyond the Standard Model. As these...
The advent of novel cryogenic sensors is opening up new paths in the search for Beyond Standard Model physics, promising to shed light on open questions such as the neutrino mass scale and even fundamental aspects of quantum mechanics. Searches in nuclear beta decays are at the forefront of new physics searches in the electroweak sector, and several efforts are currently ongoing to take...
Corrected transition rates ($Ƒt^{0^+ → 0^+}$ values) of superallowed $0^+ → 0^+$ beta decays have served as a benchmark for validating the conserved vector current (CVC) hypothesis in weak interactions. They now provide the most precise value of $V_{ud}$, the dominant top-row element of the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix. By imposing stringent constrains on the CKM...
Tests of CKM unitarity are a rigorous tool for constraining possible extensions of the Standard Model. The top-row CKM unitarity test--at the current precision level, a simpler two-flavor Cabibbo unitarity--relies on a combination of kaon, neutron and superallowed nuclear decays. The latter presently give the most precise value of $V_{ud}$ and lead to an apparent 2-3$\sigma$ unitarity deficit....
The knowledge of absolute nuclear charge radii has a significant scientific impact, from testing nuclear theories to beyond standard model physics. The absolute charge radii of almost all stable isotopes were extracted till the late 1990s, using the muonic atom spectroscopy method. In this method, a negatively charged muon beam is shot on target, the muon stops and is captured at a high...
Decays of spin-polarised and quantum-entangled hyperon-antihyperon pairs have recently presented themselves as promising hunting grounds for processes that violate fundamental symmetries, such as charge conjugation (C) and charge conjugation and parity (CP). When hyperons are produced in electron-positron annihilations, the quantum numbers of the initial state are well-known. This enables a...
