Wed·Jan 8, 2020Wednesday·January 8, 2020

1. 01*

   An extended 3-3-1 model with two scalar triplets and linear seesaw mechanism

   A. E. Cárcamo Hernández🇨🇱 · L.T. Hue🇻🇳 · Sergey Kovalenko🇨🇱 · H. N. Long🇻🇳

   Low energy linear seesaw mechanism responsible for the generation of the tiny active neutrino masses, is implemented in the extended 3-3-1 model with two scalar triplets and right handed Majorana neutrinos where the gauge symmetry is supplemented by the $A_4$ flavor discrete group and other auxiliary cyclic symmetries, whose spontaneous breaking produces the observed pattern of SM charged fermion masses and fermionic mixing parameters. Our model is consistent with the low energy SM fermion flavor data as well as with the constraints arising from meson oscillations. Some phenomenological aspects such as the $Z^{\prime }$ production at proton proton collider and the lepton flavor violating decay of the SM-like Higgs boson are discussed. The scalar potential of the model is analyzed in detail and the SM-like Higgs boson is identified.

   hep-phEur.Phys.J.Plus(2021)·24 citations
2. 02*

   Vacuum Stability in Inert Higgs Doublet Model with Right-handed Neutrinos

   Shilpa Jangid🇮🇳 · Priyotosh Bandyopadhyay🇮🇳 · P. S. Bhupal Dev🇺🇸 · Arjun Kumar🇮🇳

   We analyze the vacuum stability in the inert Higgs doublet extension of the Standard Model (SM), augmented by right-handed neutrinos (RHNs) to explain neutrino masses at tree level by the seesaw mechanism. We make a comparative study of the high- and low-scale seesaw scenarios and the effect of the Dirac neutrino Yukawa couplings on the stability of the Higgs potential. Bounds on the scalar quartic couplings and Dirac Yukawa couplings are obtained from vacuum stability and perturbativity considerations. The regions corresponding to stability, metastability and instability of the electroweak vacuum are identified. These theoretical constraints give a very predictive parameter space for the couplings and masses of the new scalars and RHNs which can be tested at the LHC and future colliders. The lightest non-SM neutral CP-even/odd scalar can be a good dark matter candidate and the corresponding collider signatures are also predicted for the model.

   hep-phJHEP(2020)·18 citations
3. 03*

   Dirac neutrinos from Peccei-Quinn symmetry: two examples

   Leon M.G. de la Vega🇲🇽 · Newton Nath🇲🇽 · Eduardo Peinado🇲🇽

   We aim to explain the nature of neutrinos using Peccei-Quinn symmetry. We discuss two simple scenarios, one based on a type-II Dirac seesaw and the other in a one-loop neutrino mass generation, which solve the strong CP problem and naturally lead to Dirac neutrinos. In the first setup latest neutrino mass limit gives rise to axion which is in the reach of conventional searches. Moreover, we have both axion as well as WIMP dark mater for our second set up.

   hep-phNPB(2020)·23 citations
4. 04*

   The role of the GPD E in the determination of the parton angular momenta

   Peter Kroll🇩🇪

   For the generalized parton distribution (GPD) E, extracted from hard exclusive processes and the Pauli form factor of the nucleon, the second moments for quarks and gluons at $t=0$ are calculated and their scale dependence analyzed. The parton angular momenta are subsequently determined and compared with other results.

   hep-phMod.Phys.Lett.A(2020)·7 citations
5. 05*

   Dynamically generated hadron resonances

   Tetsuo Hyodo🇯🇵

   Recent developments in hadron spectroscopy triggers the discussion on various exotic configurations beyond the simple three-quark state for baryons and quark-anti-quark pair for mesons. In particular, the states observed near a two-hadron threshold are often regarded as candidates of hadronic molecules, which are made of constituent hadrons and dynamically generated by the hadronic interactions. However, identification of the hadronic molecules involves several subtle difficulties which are often overlooked or underestimated. Here we summarize these subtleties and present a promising approach to distinguish the dynamically generated states from others using observable quantities.

   hep-phnucl-th1 citation
6. 06*

   A proton imagining via double parton scattering

   Matteo Rinaldi🇮🇹

   In this contribution we discuss the main outcomes of our studies on the so called double parton distribution functions (dPDFs), accessible quantities in high energy proton-proton and proton nucleus collisions, in double parton scattering processes (DPS). These new distributions are almost unknown, nevertheless they encode information on how partons inside a proton are correlated among each other. Double PDFs represent a new tool to explore the three dimensional partonic structure of hadrons. Here, we show results obtained from calculations of dPFDs. In particular we focus our attention on the impact of double correlations in experimental observables by showing how the latter could be studied in the next LHC run. We also discuss how the present knowledge on a peculiar experimental observable could unveil new information on the transverse proton structure

   hep-phnucl-thPoS(2020)·0 citations
7. 07*

   Glueballs as gravitons in holographic approaches

   Matteo Rinaldi🇮🇹

   In this contribution we present a a phenomenological analysis of the scalar glueball and scalar meson spectra within AdS/QCD models in the bottom-up approach. In particular, we consider a Light-Front QCD framework which allows to relate the AdS/QCD mode functions to the hadronic wave-functions. Such a procedure is here adopted to analyse the mixing between scalar mesons and glueballs.

   hep-phPoS(2020)·1 citation
8. 08*

   $S_3$-inspired three-Higgs-doublet models: A class with a complex vacuum

   A. Kuncinas🇳🇴 · O. M. Ogreid🇳🇴 · P. Osland · M. N. Rebelo🇵🇹

   In this paper we analyse in detail an $S_3$-symmetric three-Higgs-doublet model with a specific vacuum configuration. This analysis allows us to illustrate important features of models with several Higgs doublets, such as the possibility of having spontaneous CP violation. We start with a real potential and pick a particularly interesting complex vacuum configuration, which does not violate CP before adding soft breaking terms to the potential. We study the rôle played by different soft symmetry breaking terms. These are essential for our choice of vacuum in order to remove unwanted massless scalars which arise from the spontaneous breaking of an accidental continuous symmetry. We list scalar sector and scalar-gauge sector-couplings for the particular case we consider in detail in this work. Results presented in this paper will be useful for model building, in particular for implementations of models with $S_3$ symmetry and spontaneous CP violation, extensions of the fermionic sector with realistic Yukawa couplings and for Dark Matter studies.

   hep-phPRD(2020)·25 citations
9. 09*

   Demystifying Freeze-In Dark Matter at the LHC

   Kyu Jung Bae🇰🇷 · Myeonghun Park🇰🇷 · Mengchao Zhang🇨🇳

   Freeze-in mechanism provides robust dark matter production in the early universe. Due to its feeble interactions, freeze-in dark matter leaves signals at colliders which are often involved with long lived particle decays and consequent displaced vertices (DV). In this paper, we develop a method to read off mass spectrum of particles being involved in the DV events at the LHC. We demonstrate that our method neatly works under a limited statistics, detector resolution and smearing effects. The signature of DV at the LHC can come from either highly suppressed phase-space or a feeble coupling of particle decay processes. By measuring invisible particle mass spectrum, one can discriminate these two cases and thus extract information of dominant freeze-in processes in the early universe at the LHC.

   hep-phhep-exPRD(2020)·15 citations
10. 10*

    Excited ${\Omega }_b$ baryons and fine structure of strong interaction

    Hua-Xing Chen🇨🇳 · Er-Liang Cui🇨🇳 · Atsushi Hosaka🇯🇵 · Qiang Mao🇨🇳 · Hui-Min Yang🇨🇳

    The heavy baryon system bounded by the strong interaction has a rich internal structure, so its mass spectra can have the fine structure similar to the line spectra of atom bounded by the electromagnetic interaction. We systematically study the internal structure of $P$-wave ${\Omega }_b$ baryons and calculate their $D$-wave decay properties. The present study, together with our previous studies on their mass spectra and $S$-wave decay properties, suggest that all the four excited ${\Omega }_b$ baryons recently discovered by LHCb can be well explained as $P$-wave ${\Omega }_b$ baryons, and their beautiful fine structure is directly related to the rich internal structure of $P$-wave ${\Omega }_b$ baryons.

    hep-phhep-exEPJC(2020)·25 citations
11. 11*

    Lattice spectroscopy with focus on exotics

    Sasa Prelovsek🇸🇮

    Recent lattice QCD results on the hadron spectroscopy with beauty and charm quarks is reviewed. The focus of the review are exotic hadrons, while non-lattice approaches and conventional hadrons are reported as well. We discuss the recently discovered ${\Omega }_c^{\ast }$, a charmonium state with spin three, $P_c$ pentaquarks, $B_c(2S)$ and ${\Lambda }_b^{\ast }$, the long-standing challenges for theory $Z_c$, $Z_b$ and $X(3872)$, and we review predictions for yet undiscovered states $bb\bar{q}\bar{q}$, $\bar{b}b\bar{b}b$, highly excited and hybrid $\bar{b}b$, baryons with bottom quarks and still-missing $B_s$ mesons.

    ↳ hep-lathep-phPoS(2020)·4 citations
12. 12*

    Primordial nucleosynthesis with varying fundamental constants: Improved constraints and a possible solution to the Lithium problem

    M. T. Clara🇵🇹 · C. J. A. P. Martins🇵🇹

    Primordial nucleosynthesis is an observational cornerstone of the Hot Big Bang model and a sensitive probe of physics beyond the standard model. Its success has been limited by the so-called Lithium problem, for which many solutions have been proposed. We report on a self-consistent perturbative analysis of the effects of variations in nature's fundamental constants, which are unavoidable in most extensions of the standard model, on primordial nucleosynthesis, focusing on a broad class of Grand Unified Theory models. A statistical comparison between theoretical predictions and observational measurements of ${}^4$He, D, ${}^3$He and, ${}^7$Li consistently yields a preferred value of the fine-structure constant $\alpha$ at the nucleosynthesis epoch that is larger than the current laboratory one. The level of statistical significance and the preferred extent of variation depend on model assumptions but the former can be more than four standard deviations, while the latter is always compatible with constraints at lower redshifts. If Lithium is not included in the analysis, the preference for a variation of $\alpha$ is not statistically significant. The abundance of ${}^3$He is relatively insensitive to such variations. Our analysis highlights a viable and physically motivated solution to the Lithium problem, which warrants further study.

    ↳ astro-ph.COhep-phAstron.Astrophys.(2020)·51 citations
13. 13*

    In Leon's company, it seemed that anything might be possible

    Chris Quigg🇺🇸

    Memorial sessions celebrated Leon Lederman, Helen Edwards, and Burton Richter at the April 2019 Meeting of the American Physical Society in Denver. In the session entitled Honoring Leon Lederman, Sally Dawson gave an overview of Leon's scientific career, Marge Bardeen reviewed his work in science education, and I spoke of his years as Fermilab Director. This essay is drawn from my lecture.

    ↳ physics.hist-phhep-exhep-ph0 citations
14. 14*

    The quest for purely virtual quanta: fakeons versus Feynman-Wheeler particles

    Damiano Anselmi🇮🇹

    The search for purely virtual quanta has attracted interest in the past. We consider various proposals and compare them to the concept of fake particle, or "fakeon". In particular, the Feynman-Wheeler propagator, which amounts to using the Cauchy principal value inside Feynman diagrams, violates renormalizability, unitarity and stability, due to the coexistence of the prescriptions $\pm iϵ$. We contrast the Feynman, fakeon and Feynman-Wheeler prescriptions in ordinary as well as cut diagrams. The fakeon does not have the problems of the Feynman-Wheeler propagator and emerges as the correct concept of purely virtual quantum. It allows us to make sense of quantum gravity at the fundamental level, and places it on an equal footing with the standard model. The resulting theory of quantum gravity is perturbative up to an incredibly high energy.

    ↳ hep-thhep-phJHEP(2020)·34 citations
15. 15*

    Extended analysis for the Evolution of the Cosmological history in Einstein-aether Scalar Field theory

    Andronikos Paliathanasis🇿🇦

    We consider an Einstein-aether scalar field cosmological model where the aether and the scalar field are interacting. The model of our consideration consists the two different interacting models proposed in the literature by Kanno et al. and by Donnelly et al. We perform an extended analysis for the cosmological evolution as it is provided by the field equations by using methods from dynamical systems; specifically, we determine the stationary points and we perform the stability analysis of those exact solutions.

    ↳ gr-qchep-phPRD(2020)·15 citations
16. 16*

    Frame dependence of transition form factors in light-front dynamics

    Meijian Li🇺🇸

    We study the radiative transitions between vector and pseudoscalar quarkonia in the light-front Hamiltonian approach, and investigate the effects of using different current component and different reference frames. In practical calculations with truncated Fock spaces, transition form factors may acquire current component dependence and frame dependence, and such dependences could serve as a measure for the Lorentz symmetry violation. We suggest using the transverse current with $m_j=0$ state of the vector meson, since this procedure employs the dominant spin components of the light-front wavefunctions and is more robust in practical calculations. We calculate the transition form factor between vector and pseudoscalar quarkonia and investigate the frame dependence with light-front wavefunctions calculated from the valence Fock sector. We suggest using frames with minimal longitudinal momentum transfer for calculations in the valence Fock sector, namely the Drell-Yan frame for the space-like region and a specific longitudinal frame for the timelike region; at $q^2=0$ these two frames give the same result.

    ↳ nucl-thhep-phPoS(2020)·3 citations
17. 17*

    Strangeness and light fragment production at high baryon density

    D. Blaschke🇵🇱 · G. Röpke🇷🇺 · Yu. Ivanov🇷🇺 · M. Kozhevnikova🇷🇺 · S. Liebing🇩🇪

    We discuss medium effects on light cluster production in the QCD phase diagram within a generalized Beth-Uhlenbeck (GBU) approach by relating Mott transition lines to those for chemical freeze-out. We find that in heavy-ion collisions at highest energies provided by the LHC light cluster abundances should follow the statistical model because of low baryon densities. At low energies in the nuclear fragmentation region, where the freeze-out interferes with the liquid-gas phase transition, selfenergy and Pauli blocking effects are important. At intermediate energies the HADES, FAIR and NICA experiments can give new information. The GBU approach provides new insights to strange hadron production in this energy domain for explaining the "horn" effects.

    ↳ nucl-thhep-phSpringer Proc.Phys.(2020)·5 citations
18. 18*

    Deciphering the Archaeological Record: Cosmological Imprints of Non-Minimal Dark Sectors

    Keith R. Dienes🇺🇸 · Fei Huang🇨🇳 · Jeff Kost🇰🇷 · Shufang Su🇺🇸 · Brooks Thomas🇺🇸

    Many proposals for physics beyond the Standard Model give rise to a dark sector containing many degrees of freedom. In this work, we explore the cosmological implications of the non-trivial dynamics which may arise within such dark sectors, focusing on decay processes which take place entirely among the dark constituents. First, we demonstrate that such decays can leave dramatic imprints on the resulting dark-matter phase-space distribution. In particular, this distribution need not be thermal -- it can even be multi-modal, exhibiting a non-trivial pattern of peaks and troughs as a function of momentum. We then proceed to show how these features can induce modifications to the matter power spectrum. Finally, we assess the extent to which one can approach the archaeological "inverse" problem of deciphering the properties of an underlying dark sector from the matter power spectrum. Indeed, one of the main results of this paper is a remarkably simple conjectured analytic expression which permits the reconstruction of many of the important features of the dark-matter phase-space distribution directly from the matter power spectrum. Our results therefore provide an interesting toolbox of methods for learning about, and potentially constraining, the features of non-minimal dark sectors and their dynamics in the early universe.

    ↳ astro-ph.COhep-phPRD(2020)·32 citations
19. 19*

    Gravitational form factor constraints and their universality

    Peter Lowdon🇫🇷 · Sabrina Cotogno🇫🇷 · Cédric Lorcé🇫🇷

    By adopting a local QFT framework one can derive in a non-perturbative manner the constraints imposed by Poincaré symmetry on the form factors appearing in the Lorentz covariant decomposition of the energy-momentum tensor matrix elements. In particular, this approach enables one to prove that these constraints are in fact independent of the internal properties of the states appearing in the matrix elements. Here we outline the rationale behind this approach, and report on some of the implications of these findings.

    ↳ hep-thgr-qchep-phPoS(2020)·2 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.