Flux compactification for the critical non-Abelian vortex and quark masses

Chapter 4 deals with the stability of the proton, hence of hydrogen, and how to reconcile that stability with the baryon number nonconservation (or baryon conservation) needed to establish a matter–antimatter imbalance in the infant universe. Sakharov’s three conditions for establishing a matter–antimatter imbalance are presented. Grand unified theories and experimental searches for proton decay are described. The concept of spontaneous symmetry breaking is introduced in describing the electroweak phase transition in the infant universe. That transition is treated as the potential site for introducing the imbalance between quarks and antiquarks, via either baryogenesis or leptogenesis models. The up–down quark mass difference is presented as essential for providing the stability of hydrogen and of the deuteron, which serves as a crucial stepping stone in stellar hydrogen-burning reactions that generate the energy and elements needed for life. Constraints on quark masses from lattice QCD calculations and violations of chiral symmetry are discussed.

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Challenges for a QCD axion at the 10 MeV scale

Journal of High Energy Physics ◽

10.1007/jhep05(2021)138 ◽

2021 ◽

Vol 2021 (5) ◽

Author(s):

Jia Liu ◽

Navin McGinnis ◽

Carlos E. M. Wagner ◽

Xiao-Ping Wang

Keyword(s):

Higgs Boson ◽

Standard Model ◽

Structure Constant ◽

Fine Structure Constant ◽

Multiple Sources ◽

Standard Model Extension ◽

Mixing Angles ◽

Quark Masses ◽

Model Extension ◽

The One

Abstract We report on an interesting realization of the QCD axion, with mass in the range $$ \mathcal{O} $$ O (10) MeV. It has previously been shown that although this scenario is stringently constrained from multiple sources, the model remains viable for a range of parameters that leads to an explanation of the Atomki experiment anomaly. In this article we study in more detail the additional constraints proceeding from recent low energy experiments and study the compatibility of the allowed parameter space with the one leading to consistency of the most recent measurements of the electron anomalous magnetic moment and the fine structure constant. We further provide an ultraviolet completion of this axion variant and show the conditions under which it may lead to the observed quark masses and CKM mixing angles, and remain consistent with experimental constraints on the extended scalar sector appearing in this Standard Model extension. In particular, the decay of the Standard Model-like Higgs boson into two light axions may be relevant and leads to a novel Higgs boson signature that may be searched for at the LHC in the near future.

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DK I = 0, $$ D\overline{K} $$ I = 0, 1 scattering and the $$ {D}_{s0}^{\ast } $$(2317) from lattice QCD

Journal of High Energy Physics ◽

10.1007/jhep02(2021)100 ◽

2021 ◽

Vol 2021 (2) ◽

Author(s):

Gavin K. C. Cheung ◽

◽

Christopher E. Thomas ◽

David J. Wilson ◽

Graham Moir ◽

...

Keyword(s):

Elastic Scattering ◽

Scattering Amplitudes ◽

Lattice Qcd ◽

Finite Volume ◽

Energy Region ◽

Light Quark ◽

Bound State ◽

Vector Resonance ◽

Quark Masses ◽

Partial Waves

Abstract Elastic scattering amplitudes for I = 0 DK and I = 0, 1 $$ D\overline{K} $$ D K ¯ are computed in S, P and D partial waves using lattice QCD with light-quark masses corresponding to mπ = 239 MeV and mπ = 391 MeV. The S-waves contain interesting features including a near-threshold JP = 0+ bound state in I = 0 DK, corresponding to the $$ {D}_{s0}^{\ast } $$ D s 0 ∗ (2317), with an effect that is clearly visible above threshold, and suggestions of a 0+ virtual bound state in I = 0 $$ D\overline{K} $$ D K ¯ . The S-wave I = 1 $$ D\overline{K} $$ D K ¯ amplitude is found to be weakly repulsive. The computed finite-volume spectra also contain a deeply-bound D* vector resonance, but negligibly small P -wave DK interactions are observed in the energy region considered; the P and D-wave $$ D\overline{K} $$ D K ¯ amplitudes are also small. There is some evidence of 1+ and 2+ resonances in I = 0 DK at higher energies.

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Quarkonia Formation in a Holographic Gravity–Dilaton Background Describing QCD Thermodynamics

Particles ◽

10.3390/particles4020015 ◽

2021 ◽

Vol 4 (2) ◽

pp. 159-177

Author(s):

Rico Zöllner ◽

Burkhard Kämpfer

Keyword(s):

Quark Mass ◽

Heavy Ion ◽

Mass Dependence ◽

Holographic Model ◽

Spectral Functions ◽

Special Aspect ◽

Quark Masses ◽

Ion Collisions ◽

Heavy Quark Mass ◽

Quark Mass Dependence

A holographic model of probe quarkonia is presented, where the dynamical gravity–dilaton background was adjusted to the thermodynamics of 2 + 1 flavor QCD with physical quark masses. The quarkonia action was modified to account for the systematic study of the heavy-quark mass dependence. We focused on the J/ψ and Υ spectral functions and related our model to heavy quarkonia formation as a special aspect of hadron phenomenology in heavy-ion collisions at LHC.

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