Thu·Jun 9, 2022Thursday·June 9, 2022

1. 01*

   Geometric Minimization of Softly-Broken Potentials

   Ivo de Medeiros Varzielas🇵🇹 · Diogo Ivo🇵🇹

   We study the minimization of multi-Higgs models with symmetries that are softly-broken. The powerful method of geometric minimization enables analytic minimization of multi-Higgs models with large symmetries. When these symmetries are softly-broken, the method needs to be adapted. We propose a useful generalization that considers the effect of the soft-breaking terms to the quadratic part of the potential, by applying the procedure to restricted orbit spaces. We exemplify our novel methodology by finding and classifying the minima for an $S_4$ multi-Higgs model that is softly-broken with specific terms.

   hep-phEur.Phys.J.Plus(2023)·1 citation
2. 02*

   PeV IceCube signals and $H_0$ tension in the framework of Non-Local Gravity

   Salvatore Capozziello🇮🇹 · Gaetano Lambiase🇮🇹

   We study possible effects of non-local gravity corrections on the recent discovery by the IceCube collaboration reporting high-energy neutrino flux detected at energies of order PeV. Considering the 4-dimensional operator $\sim y_{\alpha \chi }\overline{L_{\alpha }}H\chi$, it is possible to explain both the IceCube neutrino rate and the abundance of Dark Matter, provided that non-local corrections are present in the cosmological background. Furthermore, the mechanism could constitute a natural way to address the $H_0$ tension issue.

   hep-phastro-ph.HEgr-qchep-thEur.Phys.J.Plus(2022)·11 citations
3. 03*

   Improved Theory Predictions and Global Analysis of Exclusive $\mathbf{b}\to \mathbf{s}{\mathbf{\mu }}^{+}{\mathbf{\mu }}^{-}$ Processes

   Nico Gubernari🇩🇪 · Méril Reboud🇩🇪 · Danny van Dyk🇩🇪 · Javier Virto🇪🇸

   We provide improved Standard Model theory predictions for the exclusive rare semimuonic processes $B\to K^{(\ast )}{\mu }^{+}{\mu }^{-}$ and $B_s\to \varphi {\mu }^{+}{\mu }^{-}$. Our results are based on a novel parametrization of the non-local form factors, which manifestly respects a recently developed dispersive bound. We critically compare our predictions to those obtained in the framework of QCD factorization. Our predictions provide, for the first time, parametric estimates of the systematic uncertainties due to non-local contributions. Comparing our predictions within the Standard Model to available experimental data, we find a large tension for $B\to K{\mu }^{+}{\mu }^{-}$. A simple model-independent analysis of potential effects beyond the Standard Model yields results compatible with other approaches, albeit with larger uncertainties for the $B\to K^{\ast }{\mu }^{+}{\mu }^{-}$ and $B_s\to \varphi {\mu }^{+}{\mu }^{-}$ decays. Our approach yields systematically improvable predictions, and we look forward to its application in further analyses beyond the Standard Model.

   hep-phJHEP(2022)·194 citations
4. 04*

   Quark and gluon GPDs at finite skewness from strings in holographic QCD: evolved and compared to experiment

   Kiminad A. Mamo🇺🇸 · Ismail Zahed🇺🇸

   We present a framework for constructing Generalized Parton Distributions (GPDs) using holographic QCD in the large $N_c$ limit, with a focus on low-x and finite skewness. Our approach utilizes holographic amplitudes for exclusive electroproduction processes to extract the spin-j conformal (Gegenbauer) moments of GPDs, which are then evolved to higher resolution scales using QCD evolution equations. Our evolved GPDs (reconstructed from their evolved conformal moments) are applied to analyze the electroproduction of ${\rho }^{0,+}$ and $\varphi$ mesons, and we account for non-perturbative contributions in the $s+u$ - channel using holographic QCD. The results compare well with the existing experimental data. Our GPDs provide detailed information about partonic distributions and are useful for future experimental studies and global data analyses.

   hep-phhep-exhep-thnucl-ex+1PRD(2023)·13 citations
5. 05*

   Signatures of the Yang-Mills deconfinement transition from the gluon two-point correlator

   Duifje Maria van Egmond🇫🇷 · Urko Reinosa🇫🇷

   We evaluate the longitudinal or (chromo-)electric Yang-Mills gluon propagator in the recently proposed center-symmetric Landau gauge at finite temperature [1]. To model the effect of the Gribov copies in the infrared, we use the Curci-Ferrari model which, in turn, allows us to rely on perturbative calculations. At one-loop order in the SU(2) case, the so-obtained longitudinal gluon propagator provides a clear signature for Z2 center-symmetry breaking with a singular behavior, characteristic of a continuous phase transition. This is in sharp contrast with what is found within the standard Landau gauge. We also identify various signatures for Z3 center-symmetry breaking in the SU(3) case in the form of genuine order parameters. Among those, we find that the gluon propagator, although degenerate along the diagonal color directions in the confining phase, becomes non-degenerate in the deconfined phase. Our results open new ways of identifying the transition from correlation functions both within continuum approaches and on the lattice.

   hep-phhep-lathep-thPRD(2022)·9 citations
6. 06*

   Two-loop master integrals for pseudo-scalar quarkonium and leptonium production and decay

   Samuel Abreu🇨🇭 · Matteo Becchetti🇮🇹 · Claude Duhr🇩🇪 · Melih A. Ozcelik🇩🇪

   We compute the master integrals relevant for the two-loop corrections to pseudo-scalar quarkonium and leptonium production and decay. We present both analytic and high-precision numerical results. The analytic expressions are given in terms of multiple polylogarithms (MPLs), elliptic multiple polylogarithms (eMPLs) and iterated integrals of Eisenstein series. As an application of our results, we obtain for the first time an analytic expression for the two-loop amplitude for para-positronium decay to two photons at two loops.

   hep-phJHEP(2022)·21 citations
7. 07*

   Search for charged Higgs boson in $\mu \nu$ channel within 2HDM type-III

   Rachid Benbrik (1)🇲🇦 · Mohammed Boukidi (1)🇲🇦 · Bouzid Manaut (2)🇲🇦 · Mohamed Ouchemhou (1)🇲🇦 · Souad Semlali (3)🇬🇧 · Souad Taj (2) ((1) Polydisciplinary Faculty, Laboratory of Fundamental and Applied Physics, Cadi Ayyad University, Sidi Bouzid, Safi, Morocco, (2) Polydisciplinary Faculty, Laboratory of Research in Physics and Engineering Sciences, Team of Modern and Applied Physics, Sultan Moulay Slimane University, Beni Mellal, Morocco, (3) School of Physics and Astronomy, University of Southampton, United Kingdom)🇲🇦

   We discus the muonic decay of light charged Higgs boson for $m_{H^{\pm }}\le m_t-m_b$ in the context of the generic two Higgs doublet model (2HDM) type-III. We show that for both alignment limit scenarios, the $H^{\pm }\to \mu \nu$ signal could be dominant and give alternative reachable signatures to those arising from top quark production and decay.

   hep-ph0 citations
8. 08*

   Leptons lurking in semi-visible jets at the LHC

   Cesare Cazzaniga🇨🇭 · Annapaola de Cosa🇨🇭

   This Letter proposes a new search for confining dark sectors at the Large Hadron Collider. As a result of the strong dynamics in the hidden sector, dark matter could manifest in proton-proton collisions at the Large Hadron Collider in form of hadronic jets containing stable invisible bound states. These semi-visible jets have been studied theoretically and experimentally in the fully hadronic signature where the unstable composite dark matter can only decay promptly back to Standard Model quarks. We present a simplified model based on two messenger fields separated by a large mass gap allowing dark bound states to decay into pairs of oppositely charged leptons. The resulting experimental signature is characterized by non-isolated lepton pairs inside semi-visible jets. We propose a search strategy independent from the underlying model assumptions targeting this new signature, and discuss the orthogonality with respect to the existing searches. Remaining agnostic on the shape of the di-lepton spectrum, we determine the sensitivity of a dedicated analysis to the target signal. The proposed search can claim the 3{\sigma} evidence (exclusion) of the heavier mediator up to masses of 3.5 TeV (4.5 TeV) with the full Run 2 data of the LHC. Exploiting the resonant feature of the lepton pairs can enhance the sensitivity reach on a specific model. We estimate that an analysis using the di-lepton invariant mass information can reach 5{\sigma} discovery up to masses of 3.5 TeV and improve the exclusion up to more than 5 TeV.

   hep-phhep-exEPJC(2022)·19 citations
9. 09*

   Constraining GUP Models Using Limits on SME Coefficients

   André H. Gomes🇧🇷

   In this proceedings, I outline recent efforts to constrain models based on generalized uncertainty principles (GUP) using limits on coefficients of the Standard-Model Extension. Two main results are reported: (1) bounds on isotropic GUP models are improved by a factor of $10^{10}$ compared to previous spectroscopic bounds; and (2) anisotropic GUP models are established and also constrained.

   hep-phquant-ph2 citations
10. 10*

    $a\to \pi \pi \pi$ decay at next-to-leading order in chiral perturbation theory

    Luca Di Luzio🇮🇹 · Gioacchino Piazza🇫🇷

    We discuss the construction of the two-flavour axion-pion effective Lagrangian at the next-to-leading order (NLO) in chiral perturbation theory and present, as a phenomenological application, the calculation of the decay rate of a GeV-scale axion-like particle via the channel $a\to \pi \pi \pi$. Through the NLO calculation, we assess the range of validity of the effective field theory and show that the chiral expansion breaks down just above the kinematic threshold. Alternative non-perturbative approaches are called for in order to extend the chiral description of axion-pion interactions.

    hep-phJHEP(2022)·17 citations
11. 11*

    Grand Color Axion

    Alessandro Valenti🇮🇹 · Luca Vecchi🇮🇹 · Ling-Xiao Xu🇮🇹

    We present a model that solves the strong CP problem via an axion parametrically heavier than the standard one. Within this picture the Standard Model quarks are embedded into a larger non-abelian Grand Color group that at high scales splits into ordinary QCD and an additional confining dynamics under which exotic chiral fermions are charged. Crucially, the vacuum expectation value of the axion is automatically relaxed to zero because the only renormalizable source of explicit CP violation, beyond those encoded in the topological angles, is contained in the Standard Model Yukawa couplings, and is therefore very suppressed. The axion potential is controlled by the scale of the new confining group and is much larger than the QCD contribution, such that its dynamics is less exposed to the so-called "axion quality problem". Potentially observable corrections to the effective topological angle can also arise, in our model as well as in a large class of heavy axion scenarios, from non-renormalizable Peccei-Quinn-conserving interactions, which introduce a new "heavy axion quality problem". Our model has a very minimal field content, it relies entirely on gauge invariance and does not require the introduction of additional symmetries beyond the usual one postulated by Peccei and Quinn. The phenomenology is very rich and can be tested at colliders as well as via cosmological observations. A particularly interesting portion of parameter space predicts a visible axion of mass above the GeV and decay constant larger than a few TeV.

    hep-phJHEP(2022)·37 citations
12. 12*

    Cosmological Magnetic Fields from Primordial Kerr-Newman Black Holes

    Dan Hooper🇺🇸 · Aurora Ireland🇺🇸 · Gordan Krnjaic🇺🇸

    The origin of our universe's cosmological magnetic fields remains a mystery. In this study, we consider whether these magnetic fields could have been generated in the early universe by a population of charged, spinning primordial black holes. To this end, we calculate the strength and correlation length of the magnetic fields generated by this population, and describe their evolution up to the current epoch. We find that near-extremal black holes in the mass range $M\sim 10^{28}-10^{36}\mathrm{g}$ could potentially generate magnetic fields with present day values as large as $B\sim 10^{-20}-10^{-15}\mathrm{G}$; those with $M\gtrsim 10^{38}\mathrm{g}$ could have produced even larger fields $B\gtrsim 10^{-14}\mathrm{G}$. To motivate this scenario, we briefly discuss how new physics may have induced a chemical potential which could have briefly maintained the black holes in an electrically charged state in the early universe. Finally, we comment on a correlation between the parameters of the cosmological magnetic field and the stochastic gravitational wave background coming from the merger of primordial black hole binaries as the primary observable signature of this scenario.

    ↳ astro-ph.COhep-phPRD(2023)·8 citations
13. 13*

    Pion distribution amplitude at the physical point using the leading-twist expansion of the quasi-distribution-amplitude matrix element

    Xiang Gao🇺🇸 · Andrew D. Hanlon🇺🇸 · Nikhil Karthik🇺🇸 · Swagato Mukherjee🇺🇸 · Peter Petreczky🇺🇸 · Philipp Scior🇺🇸 · Sergey Syritsyn🇺🇸 · Yong Zhao🇺🇸

    We present a lattice QCD determination of the distribution amplitude (DA) of the pion and the first few Mellin moments from an analysis of the quasi-DA matrix element within the leading-twist framework. We perform our study on a HISQ ensemble with $a=0.076$ fm lattice spacing with the Wilson-Clover valence quark mass tuned to the physical point. We analyze the ratios of pion quasi-DA matrix elements at short distances using the leading-twist Mellin operator product expansion (OPE) at the next-to-leading order and the conformal OPE at the leading-logarithmic order. We find a robust result for the first non-vanishing Mellin moment $⟨x^2⟩=0.287(6)(6)$ at a factorization scale $\mu =2$ GeV. We also present different Ansätze-based reconstructions of the $x$-dependent DA, from which we determine the perturbative leading-twist expectations for the pion electromagnetic and gravitational form-factors at large momentum transfers.

    ↳ hep-lathep-exhep-phnucl-thPRD(2022)·62 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.