Neutrino masses and Hubble tension via a Majoron in MFV

The majoron, a neutrinophilic pseudo-Goldstone boson conventionally arising in the context of neutrino mass models, can damp neutrino free-streaming and inject additional energy density into neutrinos prior to recombination. The combination of these effects for an eV-scale mass majoron has been shown to ameliorate the outstanding $$H_0$$ H 0 tension, however only if one introduces additional dark radiation at the level of $$\Delta N_{\mathrm{eff}} \sim 0.5$$ Δ N eff ∼ 0.5 . We show here that models of low-scale leptogenesis can naturally source this dark radiation by generating a primordial population of majorons from the decays of GeV-scale sterile neutrinos in the early Universe. Using a posterior predictive distribution conditioned on Planck2018+BAO data, we show that the value of $$H_0$$ H 0 observed by the SH$$_0$$ 0 ES collaboration is expected to occur at the level of $$\sim 10\%$$ ∼ 10 % in the primordial majoron cosmology (to be compared with $$\sim 0.1\%$$ ∼ 0.1 % in the case of $$\Lambda $$ Λ CDM). This insight provides an intriguing connection between the neutrino mass mechanism, the baryon asymmetry of the Universe, and the discrepant measurements of $$H_0$$ H 0 .

show abstract

“…In this context, we refer to[94] for a recent embedding of our set up within the minimal lepton flavor violating framework.…”

mentioning

confidence: 99%

The hubble tension as a hint of leptogenesis and neutrino mass generation

Escudero

Witte

2021

Eur. Phys. J. C

View full text Add to dashboard Cite

show abstract

“…+ h.c. , 3 The flavour symmetry usually associated to the MFV framework is a product of U(3) terms. In this context, new physics with flavour violating effects are expected to be heavier than a few TeV [18][19][20][21][22][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40].…”

Section: Concrete Scenariosmentioning

confidence: 99%

A new bound on CP violation in the τ lepton Yukawa coupling and electroweak baryogenesis

Alonso-González

Merlo

Pokorski

2021

J. High Energ. Phys.

View full text Add to dashboard Cite

The origin of the matter-antimatter asymmetry in the Universe is a fundamental question of physics. Electroweak baryogenesis is a compelling scenario for explaining it but it requires beyond the Standard Model sources of the CP symmetry violation. The simplest possibility is CP violation in the third generation fermion Higgs couplings, widely investigated theoretically and searched for experimentally. It has been found that the experimental bounds on the CP violation in the quark Yukawa couplings exclude their significant role in the electroweak baryogenesis, but it can be still played by the τ lepton Yukawa coupling. It is shown in this paper that, within the context of the Standard Model Effective Field Theory and assuming an underlying flavour symmetry of the Wilson coefficients, the electron dipole moment bound on the τ lepton Yukawa coupling is two orders of magnitude stronger than previously reported. This sheds strong doubts on its role in the electroweak baryogenesis, further stimulates the interest in its experimental verification and makes electroweak baryogenesis even more difficult to explain.

show abstract

“…The so-called Hubble tension stands at the level of 4-6σ [1,2]. The solution to this problem may rely on systematics in the observations or lead to a new cosmological model, but it can also be tackled from the point of view of particle physics [3].…”

Section: Introductionmentioning

confidence: 99%

Neutrino Masses and Hubble Tension via a Majoron in MFV

Arias-Aragón¹,

Fernández‐Martínez²,

González-López³

et al. 2022

Proceedings of the European Physical Society Conference on High Energy Physics — PoS(EPS-HEP2021)

Self Cite

View full text Add to dashboard Cite

The recent tension between local and early measurements of the Hubble constant can be explained in a particle physics context. A mechanism is presented where this tension is alleviated due to the presence of a Majoron, arising from the spontaneous breaking of Lepton Number. The lightness of the active neutrinos is consistently explained. Moreover, this mechanism is shown to be embeddable in the Minimal (Lepton) Flavour Violating context, providing a correct description of fermion masses and mixings, and protecting the flavour sector from large deviations from the Standard Model predictions. A QCD axion is also present to solve the Strong CP problem. The Lepton Number and the Peccei-Quinn symmetries naturally arise in the Minimal (Lepton) Flavour Violating setup and their spontaneous breaking is due to the presence of two extra scalar singlets. The Majoron phenomenology is also studied in detail. Decays of the heavy neutrinos and the invisible Higgs decay provide the strongest constraints in the model parameter space.

show abstract

Neutrino masses and Hubble tension via a Majoron in MFV

Cited by 29 publications

References 131 publications

The hubble tension as a hint of leptogenesis and neutrino mass generation

The hubble tension as a hint of leptogenesis and neutrino mass generation

A new bound on CP violation in the τ lepton Yukawa coupling and electroweak baryogenesis

Neutrino Masses and Hubble Tension via a Majoron in MFV

Contact Info

Product

Resources

About