FLASY 2022 - 9th Workshop on Flavour Symmetries and Consequences in Accelerators and Cosmology

Session

Morning Session

27 Jun 2022, 09:30

IST Congress Centre (Instituto Superior Técnico, Lisbon, Portugal)

Conveners

Morning Session

• Gustavo Branco

Morning Session

• Jorge Romão

Morning Session

• Francisco Botella

Morning Session

• Ferruccio Feruglio

Morning Session

• Gustavo Burdman

Morning Session

• Myriam Mondragón

Morning Session

• Stefan Antusch

Morning Session

• Ernest Ma

Morning Session

• Morimitsu Tanimoto

Morning Session

• Manfred Lindner

86. Overview of the three-neutrino oscillation picture

Mariam Tórtola

27/06/2022, 09:30

This talk will present the current status of global analyses of neutrino oscillation data in the three-flavor framework. I will discuss the hints in favor of normal mass ordering and maximal CP violation and the tensions that appear from the combination of different data samples. I will also comment on future opportunities to improve our knowledge of the oscillation picture as well as on its...

49. Lepton flavor phenomena in modular symmetry

MORIMITSU TANIMOTO

27/06/2022, 10:00

We discuss the lepton flavor violation (LFV), the leptonic magnetic moments (g-2)
and the electric dipole moment (EDM) of the electron in the Standard-Model Effective Field Theory (SMEFT) with the modular symmetry. We take the level 3 finite modular group for the flavor symmetry, and discuss the dipole operators at nearby fixed point $\tau=i$, where observed lepton masses and mixing angles...

47. Automorphic forms and fermion masses

Ferruccio Feruglio

27/06/2022, 11:00

Symmetry principles have long been applied to the flavour puzzle. In a bottom-up approach, the variety of possible symmetry groups and symmetry breaking sectors is huge, the predictability is reduced and the number of allowed models diverges. A relatively well-motivated and more constrained framework is provided by supersymmetric theories where a discrete subgroup Γ of a non-compact Lie group...

60. UV origin of modular flavor symmetries

Michael Ratz

27/06/2022, 11:30

Modular flavor symmetries are a new and exciting approach to the flavor problem. Simple, successful models have been proposed in the bottom-up approach. In this talk the geometric interpretation and intuition of modular flavor symmetries will be provided by deriving modular flavor symmetries from a torus. It will also be discussed how they emerge from UV complete string compactifications.

71. Flavor-Changing Neutral Currents in the Higgs Sector

Marc Sher

28/06/2022, 09:30

In extensions of the Higgs sector, tree-level flavor-changing neutral currents will generally occur unless suppressed with a discrete symmetry. I'll review three different approaches to tree-level FCNC. The first, with a popular mass-matrix ansatz, appears to be under severe experimental challenge. The second involves models with "minimal flavor violation" - a common UV completion is...

84. The Muon-Specific Model

Pedro Ferreira

28/06/2022, 10:00

The Muon-Specific Model is a version of the Two Higgs Doublet Model (2HDM) with a flavour-breaking symmetry that enhances or suppresses scalars' interactions with muons, compared with other 2HDMs. It was proposed by Abe, Sato, and Yagyu in 2017 in an attempt to explain the muon g-2 anomaly. We will review the main tenets of the model, including the interesting feature of it containaing...

63. Fermion Mass Hierarchies and Modulus Stabilisation in Modular-Invariant Models of Flavour

Serguey Petcov (INFN/SISSA, Trieste, Italy, and Kavli IPMU, Univ. of Tokyo, Japapn)

28/06/2022, 11:00

In modular-invariant models of flavour, hierarchical fermion mass matrices may
arise solely due to the proximity of the modulus $\tau$ to a point of
residual symmetry. This mechanism does not require flavon fields
and may produce viable fermion (charged-lepton and quark)
mass hierarchies without fine-tuning. Models of lepton flavour in which
the indicated idea is realised are presented....

58. Precision of Model Predictions and Modular Flavor Symmetries

Mu-Chun Chen (University of California - Irvine)

28/06/2022, 11:30

I will discuss the precision of predictions in models based on modular flavor symmetries aiming to address the fermion mass and mixing problem. I will describe a framework based on quasi-eclectic modular symmetries and its potential to reduce the theoretical uncertainties of model predictions.

80. Modular Flavor Symmetries and CP from the top down

Andreas Trautner

28/06/2022, 12:00

The framework of compactified heterotic string theory offers consistent UV completions of the Standard Model of particle physics. In this approach, the existence of flavor symmetries beyond the Standard Model is imperative and the flavor symmetries can be derived from the top down. Such a derivation uncovers a unified origin of traditional discrete flavor symmetries, discrete **modular...

91. On gauge and matter unification in composite Higgs models

Sebastian Jaeger

29/06/2022, 09:00

The gauge and matter structure of the SM hint at gauge and matter unification not far below the Planck scale. Preserving this in composite Higgs imposes restrictions on the embedding of the SM symmetry, and the standard composite-Higgs custodial symmetries, into the strong-sector symmetry group. I describe a minimal setup which, remarkably, automatically includes a vector leptoquark of the...

67. Scotogenic A_5 to A_4 Dirac Neutrinos

Ernest Ma

29/06/2022, 09:30

Radiative Dirac neutrino masses and their mixing are linked to dark matter through the non-Abelian discrete symmetry A_5 of the 4-dimensional pentatope, softly broken to A_4 of the 3-dimensional tetrahedron. Dark neutral fermions are produced through Higgs decay.

78. Flavour anomalies meet flavour symmetry

Claudia Hagedorn

29/06/2022, 10:00

We propose an extension of the Standard Model with a leptoquark and a flavour symmetry that is the direct product of a dihedral and a cyclic group. We show that both the flavour anomalies in $R(D)$ and $R(D^\star)$ and of the anomalous magnetic moment of the muon as well as the charged fermion mass hierarchy and the quark mixing pattern can be explained. At the same time, constraints imposed...

50. Neutrino transition in dark matter

Eung Jin Chun

29/06/2022, 11:00

An ultralight dark matter may have interesting implications in neutrino physics which have been studied actively in recent years. There can occur yet unexplored medium effect of neutrino transition which must be taken into account when describing the oscillations of neutrinos propagating through dark matter. Strong constraints on the model parameters are obtained considering the solar neutrino...

74. Multi-component dark sectors: symmetries, asymmetries and conversions

Juan Herrero Garcia (IFIC, UV/CSIC)

29/06/2022, 11:30

Dark matter may be part of a complex dark sector, possibly involving several stable components. It may also comprise both symmetric and asymmetric components. In this talk, I will present the framework needed to compute the relic abundance in these extended dark sectors, discuss the role of dark matter conversions, and show some recent results.

73. Neutrino phenomenology in the presence of light gauge bosons

Eduardo Peinado

29/06/2022, 12:00

Neutrino masses and the existence of non-baryonic Dark Matter (DM) are, together with the Baryon asymmetry in the Universe, three pieces of evidence that the Standard Model is not the final theory of particle physics. In this talk, we will discuss scenarios with a gauged U(1)´ symmetry in the light of current and future coherent elastic neutrino-nucleus scattering experiments. We will also...

70. Neutrino and Flavour Models, from the Planck Scale to the Electroweak Scale

Steve King

30/06/2022, 09:00

We discuss various approaches to the flavour problem of the Standard Model, including the LFU violation anomalies in B decays, in which the Yukawa couplings may be determined by symmetry or anarchy and may be renormalizable or effective. If the Yukawa couplings are effective, in principle the flavour scale can be anywhere from the Planck scale to the Electroweak scale, where SUSY/GUTs suggest...

92. Quantum-Gravitational Decoherence and the Number of Flavors in the Universe

Heinrich Päs (TU Dortmund)

30/06/2022, 09:30

We discuss the interplay of wave packet decoherence and decoherence induced by quantum gravity via interactions with spacetime foam for high energy astrophysical neutrinos. In this context we point out a compelling consequence of the expectation that quantum gravity should break global symmetries, namely that quantum-gravity induced decoherence may not only be the most sensitive probe for...

61. Completing the Standard Model

Jose W.F. Valle

30/06/2022, 10:00

In this talk I will describe symmetry-based approaches to some of the main drawbacks of the standard model.

81. Progress in baryogenesis via neutrino oscillations

Nuria Rius

30/06/2022, 11:00

Low energy baryogenesis via sterile neutrino oscillations has received recently considerable attention, since it can be testable in future experiments such as SHIP and FCC. Focusing on the minimal model with just two heavy sterile neutrinos, we have studied bounds on the mixing among them and the active ones from successful baryogenesis, both through a numerical scan and by deriving analytic...

72. VISHnu: flavour-variant DFSZ axion model for inflation, neutrino masses, dark matter and baryogenesis

Raymond Volkas

30/06/2022, 11:30

The nuDFSZ model identifies the Peccei-Quinn scale with the type-I seesaw scale, so accommodates neutrino mass generation and baryogenesis via leptogenesis. It also features axion dark matter, and of course solves the strong-CP problem. In this talk I will introduce VISHnu, a modification of nuDFSZ that uses flavour-dependent Higgs Yukawa couplings to (i) remove the usual DFSZ cosmological...

88. Unconventional axions and ALPs

Belen Gavela

30/06/2022, 12:00

Axions which solve the strong CP problem but can be much heavier or much lighter than the canonical QCD axion will be discussed, as well as recent theoretical developments protecting ALPs from ultraviolet sensitivity and resulting in degenerate ALPs.

94. Flavour seesaw and phenomenological consequences

Manfred Lindner (Max-Planck-Institut fuer Kernphysik, Heidelberg, Germany)

01/07/2022, 09:00

56. Implications of the Zero 1-3 Flavour Mixing Hypothesis: Predictions for \theta_{23}^PMNS and \delta_PMNS$

Stefan Antusch

01/07/2022, 09:30

We revisit mixing sum rule relations in the lepton and quark sectors under the assumption that the 1-3 elements of the flavour mixing matrices ($V^u_L,V^d_L,V^e_L,V^\nu_L$) are zero in the flavour basis. We consider the exact relations resulting from the validity of this zero 1-3 flavour mixing hypothesis and analyse their implications based on the current experimental data, including effects...

77. Momentum Dependence in Higgs Couplings from Physics Beyond the Standard Model

Gustavo Burdman (University of Sao Paulo, Brazil)

01/07/2022, 10:00

I will consider momentum dependent effects in Higgs couplings generated by physics beyond the standard model. I will explore a model dependent approach, in which we can compute fully the non-local effects from physics not directly reachable by the LHC energy. This information is encapsulated in form factors. I will briefly compare this method with the effective field theory approach. I will...

85. Precision CEvNS

Danny Marfatia

01/07/2022, 11:00

I will discuss the impact of quenching factor and nuclear form factor uncertainties on the interpretation of coherent elastic neutrino-nucleus scattering data.

66. Coherent elastic neutrino-nucleus scattering in the Standard Model and beyond

Valentina De Romeri

01/07/2022, 11:30

In this talk, I will present the physics potential of the coherent elastic neutrino-nucleus scattering (CEvNS) process. I will first briefly review the status of current observations. Then I will comment about their implications for both precision tests of the Standard Model and for new physics in the neutrino sector. Finally I will discuss the relevance of these measurements for direct dark...

75. Double Beta Decay as a Probe of New Physics

Frank F Deppisch

01/07/2022, 12:00

Neutrinoless double beta decay is crucial in determining the nature of neutrinos, and thereby the mechanism beyond the Standard Model (SM) with which they acquire their masses. I will review searches for neutrinoless double beta decay and discuss the prospects and consequences of observing neutrinoless double beta decay. I will likewise highlight related modes such as Majoron emission and...

54. CP violation and W mass modification from Dark Photon Kinetic Mixing

Xiao-Gang He (NTU/SJTU)

I report new results on CP violation and W mass modification from Dark Photon Kinetic Mixing.

89. Phenomenology of a Composite 2HDM

Stefano Moretti (Science and Technology Facilities Council STFC (GB))

We present the theoretical construction of a Composite 2HDM and discuss some of its possible experimental manifestations.