Conveners
Parallel session I: 1-I
- Matteo Parriciatu (Istituto Nazionale di Fisica Nucleare)
Parallel session I: 2-I
- Matteo Parriciatu (Istituto Nazionale di Fisica Nucleare)
Parallel session I: 3-I
- Davide Meloni (Istituto Nazionale di Fisica Nucleare)
Parallel session I: 4-I
- Joao Penedo (INFN Roma Tre)
In this talk, I will discuss a type-ii seesaw using the modular $A_4$ flavour symmetry. We propose a simple and minimalistic model that restricts the neutrino oscillation parameter space and, most importantly, introduces a sum rule in the physical neutrino masses. When combined with the mass squared differences observed in neutrino oscillations, this sum rule determines the absolute neutrino...
A $SU(3)_C\times SU(3)_L \times U(1)_X$ extension of the gauge symmetry of the Standard Model with $A_4$ modular symmetry and radiative linear seesaw is proposed. The gauge extension of the SM offer an opportunity to add new scalar fields to the model that can be used in Yukawa interactions to construct the neutrino mass matrix. In addition, $A_4$ modular symmetry is used as a flavour symmetry...
In this work, we study modular symmetries in type IIB flux landscape by investigating symplectic basis transformations of period vectors on toroidal orbifolds.
To fix explicit cycles of a third-cohomology basis regarding the untwisted complex structure modulus, which is necessary to construct the period vectors, we find that the following two symmetries are required for the period vectors:...
We propose a numerical method of searching for parameters with experimental constraints in generic flavor models by utilizing diffusion models, which are classified as a type of generative artificial intelligence (generative AI). As a specific example, we consider the $S_{4}^\prime$ modular flavor model and construct a neural network that reproduces quark masses, the CKM matrix, and the...
The explanation of neutrino masses and mixing still represents one of the open questions of the so-called “SM flavor puzzle” today. The purpose of my work is to provide a possible explanation of this problem, introducing an extension of the Standard Model based on a continuous $U(2)$ flavor symmetry (which is locally isomorphic to $SU(2) \times U(1)$), indicated as $U(2)_F$. This symmetry is...
Building on the realistic U(2) flavor model proposed a few years ago by Linster and Ziegler, we conduct a comprehensive study of possible neutrino mass textures arising from the seesaw mechanism. We identify a set of viable models that provide an excellent fit to low-energy Standard Model flavor observables including neutrinos. Additionally, within an Effective Field Theory framework, we...
In Nelson-Barr theories built to solve the strong CP problem, vector-like quarks (VLQs) transmit the spontaneous CP breaking from a scalar sector to the CP conserving version of the SM. We perform the full one-loop matching calculations at the CP breaking scale up to dimension five and partial matching calculations at the VLQ scale to track the relevant corrections to the theta parameter at...
In this talk, I will describe minimal DFSZ models extended with two right-handed neutrinos to realize the minimal type-I seesaw mechanism. The models incorporate flavored U(1) PQ symmetries that account for the observed pattern of quark and lepton masses and mixings. I will discuss the resulting phenomenology, including axion dark matter and cosmology, axion couplings to photons and fermions,...
I will discuss our recent paper arXiv:2501.13156 where we propose a KSVZ-type axion framework in which vector-like quarks (VLQ) and coloured scalars generate Dirac neutrino masses radiatively. The global Peccei-Quinn symmetry (under which the exotic fermions are charged) addresses the strong CP problem and ensures the Dirac nature of neutrinos. The axion also accounts for the observed...
We study the stabilization of an modulus by Coleman-Weinberg potential generated by coupling with matter fields, which is controlled by modular flavor symmetry. In this model we can not only regard the $\mathrm{Re}\,\tau$ direction as the QCD axion but also propose new potential model for inflation using the same potential.
We explore the viability of axion-like particle (ALP) effective field theories (EFTs) where the ALP mass $m_a$ is comparable to or larger than the symmetry-breaking scale $f_a$, challenging the conventional hierarchy $m_a < f_a$. Using a data-driven approach, we analise four key observables: the anomalous magnetic moments of the electron and muon, as well as decays ($\mu\to e\gamma$) and...
Part of the community has intensively searched for ALP signals, as well as conducted dedicated data analyses to identify potential evidence of New Physics compatible with an ALP, resulting in constraints on the ALP parameter space. Therefore, it is now the time to present a tool, ALPaca, that facilitates the combination among the different information on ALP physics.
The focus of this talk...
We study the most general Lagrangian for muon decay at low energies, including light Dirac right-handed neutrinos ($\nu$WEFT), in the COHERENT experiment at the Spallation Neutron Source at Oak Ridge National Laboratory. Using the COHERENT data, we derive the first direct constraint on the Michel parameters governing the $\bar\nu_\mu$ energy distribution. We also discuss future sensitivities...
We discuss an SO(10) model where a dimension five operator induces kinetic mixing between the abelian subgroups at the unification scale. We discuss gauge coupling unification and proton decay in this model, as well as the appearance of superheavy quasistable strings, which can explain the PTA data.
The NOvA and T2K electron neutrino appearance data, show a persisting tension in the determination of the CP-phase delta_CP. We quantify the statistical level of the tension and point out that it may represent a hint of new physics BSM. In particular, we find a preference for flavor-changing non.standard neutrino interactions (NSI) at the non-negligible 2 sigma level. In addition, we point out...
In the LHC regime, the mixing between doublet and triplet scalars enriches the phenomenology of the scalar sector. However, electroweak precision observables place stringent constraints on scalar multiplets larger than doublets under the SU(2)_L gauge group. Notable exceptions are the well-established Georgi-Machacek (GM) model and the recently proposed extended Georgi-Machacek (eGM) model –...
I will describe how light states like a light sterile neutrino an an ALP( axion like particle) can be probed in various flavor experiments. I will discuss their signatures in B decays and also study the implications of these states in other sectors like rare Kaon decays and neutrino experiments. In particular I will discuss how these light states may resolve some of the existing $B$ anomalies.
To address the smallness of neutrino masses and the observed large neutrino mixing, we propose a hybrid framework that synergistically combines the canonical seesaw mechanism with radiative mass generation. This model is embedded in the A₄ non-Abelian discrete flavor symmetry, whose spontaneous breaking generates correct neutrino mixing patterns and stabilizes dark matter through a conserved...
