Conveners
BSM physics
- Venus Keus (Dublin Institute for Advanced Studies (DIAS))
BSM physics
- Otari Sakhelashvili (Sydney University)
BSM physics
- Tobias Felkl (University of New South Wales)
I will describe how gravitational waves from a cosmological first-order phase transition can be correlated with microlensing signals of Fermi balls (or gamma-ray signals of primordial black holes) produced during the phase transition. A measurable amount of dark radiation is also typically expected.
We derive improved stellar luminosity limits on a generic light CP-even scalar field S mixing with the Standard Model (SM) Higgs boson from the supernova SN1987A, the Sun, red giants (RGs) and white dwarfs (WDs). For the first time, we include the geometric effects for the decay and absorption of S particles in the stellar interior. For SN1987A and the Sun, we also take into account the...
The electroweak sector of the MSSM is in agreement with DM relic density measurements, direct detection (DD) limits, LHC searches, as well as the 4.2 $\sigma$ deviation found for the anomalous magnetic moment of the muon. Taking all constraints into account we derive upper and lower bounds on several SUSY mass scales. We investigate the prospects for DD experiments. We demonstrate that...
Dark matter direct searches place very stringent constraints on the possible DM candidates proposed in extensions of the Standard Model. There are however models where these constraints are avoided. One of the simplest and most striking examples comes from a straightforward Higgs portal pseudoscalar DM model with a softly broken U(1) symmetry. In this model the tree-level DM-nucleon scattering...
In particle physics, the Standard Model makes extremely accurate predictions, but experimental and observational facts like neutrino oscillation or baryon number asymmetry suggest the existence of physics beyond the Standard Model (BSM). If the BSM exists at energy scales higher than the Standard Model, its effects can be approximately described by the Standard Model Effective Field Theory...
I argue that quantum gravity effects due to the coloured gravitational instantons compromise the standard axion solution to the strong CP problem. I propose a new solution within a theory that requires two axion fields and is dubbed the companion axion model. Some phenomenological and cosmological implications of this model are discussed.
The dynamics of hidden gauge fields coupled with an axion field during inflation is an interesting source of primordial gravitational wave perturbations. For a large axion decay constant, the subdominant energy density of the axion field would be transformed to that of the extra radiation of the hidden gauge bosons by the axion decay. Part of parameter space of such a model will be tested by...
It is remarkable that the matter fields in the Standard Model (SM) are apparently unified into the SU(5) representations. A straightforward explanation of this fact is to embed all the SM gauge groups into a simple group containing SU(5), i.e., the grand unified theory (GUT). Recently, however, a new framework “fake GUT” has been proposed. In this new framework, the apparent matter unification...
It has been recently pointed out that in certain axion models it is possible to suppress simultaneously both the axion couplings to nucleons and electrons, realising the so-called astrophobic axion scenarios, wherein the tight bounds from SN1987A and from stellar evolution of red giants and white dwarfs are greatly relaxed. So far, however, the conditions for realising astrophobia have only...
The asymmetric dark matter (ADM) paradigm is motivated by the apparent coincidence between the cosmological mass densities of visible and dark matter, $\Omega_\mathrm{DM} \simeq 5\Omega_\mathrm{VM}$. However, most ADM models only relate the number densities of visible and dark matter, and do not motivate the similarity in their particle masses. One exception is a framework introduced by Bai...
The coupling between the magnetization and the lattice of a ferromagnet gives rise to interesting dynamics. Specifically, in low magnetic fields a levitated magnet should precess, like a spinning top. Such behaviour will enable the use of a ferromagnet as a gyroscope, as a system to test for exotic bosons, and, in the future, to test experimentally the gyrogravitational ratio.
Recently, a...
The rate of semitauonic B decays has been consistently above theory expectations since these decays were first measured. Also, there are various anomalies in flavour-changing neutral current decays b->sll. The low-background collision environment along with the possibility of partially or fully reconstructing one of the two B mesons in the event offer high precision measurements of...
Belle has unique reach for a broad class of models that postulate the existence of dark matter particles with MeV—GeV masses. This talk presents recent world-leading physics results from Belle II searches for dark Higgstrahlung and Z′ decays; as well as the near-term prospects for other dark-sector searches.
Determining the nature of New Physics extensions to the Standard Model is one of the most pressing issues for Particle Physics. Well-motivated theories employ New Physics to solve the strong CP, hierarchy or axion quality problems by introducing new pseudoscalar particles which are weakly coupled to the standard model. These axion-like particles can have MeV – GeV masses and predominantly...
