The structure around $p\bar{p}$ threshold in $J/\psi$ radiative decaysYang, Qin-He;Guo, Di;Dai, Ling-Yun
doi: 10.48550/arXiv.2209.10101pmid: N/A
Abstract: In this paper, we study the structure around $p\bar{p}$ threshold that appears in $\eta'\pi^+\pi^-$, $3(\pi^+\pi^-)$ and $K_S^0K_S^0\eta$ invariant mass spectra in the processes of relevant $J/\psi$ radiative decays. The $N\bar{N}$ re-scattering is taken into account, and the distorted-wave Born approximation is applied to get the decaying amplitude through a two-step process: $J/\psi\to\gamma N\bar{N}\to\gamma\eta'\pi^+\pi^-$, $\gamma 3(\pi^+\pi^-)$ and $\gamma K_S^0K_S^0\eta$. The $N\bar{N}$ scattering amplitudes are obtained by solving the Lippmann-Schwinger equation with the potentials given by chiral effective field theory. To fix the unknown couplings, we fit the amplitudes to the data sets of the latest measurements on the invariant mass spectra of $J/\psi$ radiative decays, as well as the phase shifts and inelasticities given by partial wave analysis. We vary the cut-offs ($R$=0.9, 1.0, and 1.1 fm) and find that the solutions are stable. The structures around $p\bar{p}$ threshold found in the processes of $J/\psi\to\gamma\eta'\pi^+\pi^-$, $J/\psi\to\gamma3(\pi^+\pi^-)$ and $J/\psi\to\gamma K_S^0K_S^0\eta$ can be attributed to threshold behaviour of $N\bar{N}$ intermediate states.
Boson-jet and jet-jet azimuthal correlations at high transverse momentavan Kampen, A. M.;Martinez, A. Bermudez;Banos, L. I. Estevez;Hautmann, F.;Jung, H.;Mendizabal, M.;Figueroa, K. Moral;Prestel, S.;Monfared, S. Taheri;Wang, Q.;Wichmann, K.;Yang, H.
doi: 10.48550/arXiv.2209.13945pmid: N/A
Abstract: We discuss our recent results on azimuthal distributions in vector boson + jets and multi-jet production at the LHC, obtained from the matching of next-to-leading order (NLO) perturbative matrix elements with transverse momentum dependent (TMD) parton branching. We present a comparative analysis of boson-jet and jet-jet correlations in the back to-back region, and a study of the theoretical systematic uncertainties associated with the matching scale in the cases of TMD and collinear parton showers.
Formulating E- & T-Model Inflation in SupergravityPallis, C.
doi: 10.1088/1742-6596/2375/1/012012pmid: N/A
Abstract: We present novel realizations of E- and T-model inflation within Supergravity which are largely associated with the existence of a pole of order one and two respectively in the kinetic term of the inflaton superfield. This pole arises due to the selected logarithmic Kahler potentials K, which parameterize hyperbolic manifolds with scalar curvature related to the coefficient (-N)<0 of a logarithmic term. The associated superpotential W exhibits the same R charge with the inflaton-accompanying superfield and includes all the allowed terms. The role of the inflaton can be played by a gauge singlet or non-singlet superfield. Models with one logarithmic term in K for the inflaton, require N=2, some tuning -- of the order of 10^-5 -- between the terms of W and predict a tensor-to-scalar ratio r at the level of 0.001. The tuning can be totally eluded for more structured K's, with N values increasing with r and spectral index close or even equal to its present central observational value.
Light Sterile Neutrinos, Left-Right Symmetry, and $0\nu\beta\beta$ Decayde Vries, Jordy;Li, Gang;Ramsey-Musolf, Michael J.;Vasquez, Juan Carlos
doi: 10.48550/arXiv.2209.03031pmid: N/A
Abstract: We investigate neutrinoless double beta ($0\nu\beta\beta$) decay rates in minimal left-right symmetric models in presence of relatively light right-handed neutrinos. By use of an effective field theory approach, we systematically include all contributions in the model as well as the dependence of the decay amplitude on the masses of right-handed neutrinos. In type-I and type-II seesaw scenarios, we analyze the impact of right-handed neutrinos heavier than about 10 MeV, showing that this effect can lead to a detection of $0\nu\beta\beta$ decay in the next-generation experiments even for the normal hierarchy and a relatively large right-handed scale set by the mass of hypothetical right-handed gauge bosons. Finally, we comment on a possible connection between light right-handed neutrinos and the strong CP problem.
Dilaton Effective Field TheoryAppelquist, Thomas;Ingoldby, James;Piai, Maurizio
doi: 10.48550/arXiv.2209.14867pmid: N/A
Abstract: We review and extend recent studies of dilaton effective field theory (dEFT) which provide a framework for the description of the Higgs boson as a composite structure. We first describe the dEFT as applied to lattice data for a class of gauge theories with near-conformal infrared behavior. It includes the dilaton associated with the spontaneous breaking of (approximate) scale invariance, and a set of pseudo-Nambu-Goldstone bosons (pNGBs) associated with the spontaneous breaking of an (approximate) internal global symmetry. The theory contains two small symmetry-breaking parameters. We display the leading-order (LO) Lagrangian, and review its fit to lattice data for the $SU(3)$ gauge theory with $N_f = 8$ Dirac fermions in the fundamental representation. We then develop power-counting rules to identify the corrections emerging at next-to-leading order (NLO) in the dEFT action. We list the NLO operators that appear and provide estimates for the coefficients. We comment on implications for composite-Higgs model building.
Recovering the conformal limit of color superconducting quark matter within a confining density functional approachIvanytskyi, Oleksii;Blaschke, David
doi: 10.48550/arXiv.2209.02050pmid: N/A
Abstract: We generalize a recently proposed confining relativistic density-functional approach to the case of density dependent vector and diquark couplings. The particular behavior of these couplings is motivated by the non-perturbative gluon exchange in dense quark matter and provides the conformal limit at asymptotically high densities. We demonstrate that this feature of the quark matter EoS is consistent with a significant stiffness in the density range typical for the interiors of neutron stars. In order to model these astrophysical objects we construct a family of hybrid quark-hadron EoSs of cold stellar matter. We also confront our approach with the observational constraints on the mass-radius relation of neutron stars and their tidal deformabilities and argue in favor of a quark matter onset at masses below ${1.0 ~\rm M}_\odot$.
Medium-modifications of $g\to c \bar{c}$ splittingPark, Sohyun
doi: 10.48550/arXiv.2209.15433pmid: N/A
Abstract: We study medium-modifications of the gluon splitting into a quark and anti-quark pair. Applying the Baier-Dokshitzer-Mueller-Peigné-Schiff and Zakharov (BDMPS-Z) formalism, we derive a path-integral formula for the in-medium $g\to q \bar{q}$ splitting function in the close-to-eikonal limit. Our analysis shows that there are two qualitatively different medium effects: transverse momentum broadening of $q \bar{q}$ pairs and enhanced production of such pairs. We note that both effects are numerically sizeable if the average momentum transfer from the medium to the parton is at the quark mass scale. In ultra-relativistic heavy-ion collisions, this condition is realized by charm quarks, therefore we focus our numerical analysis on the medium-modifications of $g\to c \bar{c}$ splitting.
Shape of the hot topological charge density spectral functionLaine, M.;Niemi, L.;Procacci, S.;Rummukainen, K.
doi: 10.48550/arXiv.2209.13804pmid: N/A
Abstract: After motivating an interest in the shape of the topological charge density spectral function in hot Yang-Mills theories, we estimate it with the help of thermally averaged classical real-time simulations, for $N_{\rm c} = 2,3$. After subtracting a perturbative contribution at large frequencies, we observe a non-trivial shape at small frequencies (a dip rather than a peak), interpolating smoothly towards the sphaleron rate at zero frequency. Possible frequency scales making an appearance in this shape are discussed. Implications for warm axion inflation and reheating, and for imaginary-time lattice measurements of the strong sphaleron rate, are recapitulated.