arXiv subjects

Adriana Menkara

Publications and source records attributed to Adriana Menkara.

4 recordsLinked to original sources

arXiv2025

pNGB Higgs Naturalness at a Tipping Point

In scenarios where the Higgs is viewed as a pseudo Nambu-Goldstone boson (pNGB) the question of naturalness finds itself, from a phenomenological perspective, at a tipping point between direct searches and precision. If, by the end of the High-Luminosity LHC operation, all experimental results were to remain consistent with the Standard Model, precision Higgs coupling measurements will begin to drive the naturalness tension. To illustrate this from a fresh perspective we construct a maximally natural `Kitchen Sink' model, throwing into the mix three approaches to symmetry-based naturalness: Supersymmetry, Twin Higgs, and pNGB Higgs models with a Gegenbauer potential. In other words, we build a `Supersymmetric Gegenbauer's Twin' model. This model not only maximises naturalness, at least from a technical perspective, but can also interpolate between all three ingredients smoothly, revealing the interplay between direct exploration and precision. Implications for FCC-ee and FCC-hh are discussed.

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arXiv2024

Towards self-consistent models for Inflation and Early Universe Cosmology

In this PhD thesis we take smalls steps towards linking our knowledge of the Early Universe with our knowledge of particle physics. Chapters 3, 4 and 5 deal with Higgs inflation UV completions and their phenomenology. In Chapter 6 we consider a model for natural inflation with twin waterfalls, in which a Z2 symmetry is responsible for the radiative stability of the potential. Including a separate Z2' symmetry allows us to identify one of the waterfall fields with Dark Matter, that can be sufficiently produced during preheating. In Chapter 7, we take conformal couplings and expand around the pole of the Einstein-frame kinetic term. Using this structure we can recover successful Higgs inflation without the need of a large non-minimal coupling. Finally, in Chapter 8 we apply the setup to the Peccei-Quinn field responsible for the axion solution the Strong CP problem, and reproduce the observed Dark Matter relic abundance through the axion kinetic misalignment mechanism.

hep-ph↗

arXiv2023

Graceful exit from inflation and reheating with twin waterfalls

We study the hybrid inflation with a pseudo-Nambu-Goldstone boson inflaton and two waterfall scalar fields. The $Z_2$ symmetry for the waterfall fields keeps inflaton potential flat against quantum corrections coming from the waterfall couplings, and it is broken spontaneously in the vacuum without a domain wall problem within the Hubble horizon of our universe. We show that the $Z_2$ invariant Higgs portal couplings to the waterfall fields are responsible for the reheating process, leading to a sufficiently large reheating temperature after inflation. In the presence of an extra $Z'_2$ symmetry, one of the waterfall fields or another singlet scalar field becomes a dark matter candidate. In particular, we find that preheating is sufficient to account for the correct relic density of the waterfall dark matter.

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arXiv2022

Pseudo-Nambu-Goldstone inflation with twin waterfalls

We propose a pseudo-Nambu-Goldstone inflation where twin waterfall fields coupled to the inflaton are responsible for the graceful exit from inflation by a waterfall transition. In this scenario, the $Z_2$ symmetry for the waterfall fields and the inflaton protects the inflaton potential against dangerous quantum corrections coming from the waterfall couplings. We show that there is a wide range of natural model parameters and initial conditions for a successful inflation and discuss the reheating process by the perturbative decay of the waterfall field with a $Z_2$ invariant Higgs portal. We also present a microscopic model for the inflaton couplings to the twin waterfall fields in the context of a dark QCD with light and heavy quarks.

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