We propose an extra-dimension framework on the orbifold $S^1/Z_2$ to understand the origin of the fermion mass and mixing hierarchies. Introducing the flavor symmetry $G_F(=\mathrm{non}\text{−}\mathrm{Abelian}\times \mathrm{Abelian})$ as well as the extra gauged $U(1)$ symmetries through the bulk, we regard the $SU(2)$-singlet and -doublet fermions in the Standard Model (SM) to be localized at the separate 3-branes and let the extra $SU(2)$-singlet flavored fermions in the bulk couple to the SM fermions at the 3-branes. The extra $U(1)$ symmetries satisfy the $U(1)$ gravitational anomaly free condition, playing a crucial role in achieving the desirable fermion mass and mixing hierarchies and making the flavored axion naturally light. The singlet scalar fields, the flavon fields, are responsible for the spontaneous breaking of $G_F$ on the two 3-branes, while the $SU(2)$-singlet flavored fermions are integrated out to give rise to the effective Yukawa couplings for the SM fermions endowed with the information of $G_F$ breaking in the two sectors. The flavored axion from the Peccei-Quinn symmetry is also proposed for solving the strong $CP$ problem and being a dark matter candidate in our model.

While the tripletlike Higgses up to a few hundred GeV masses are already excluded for a vast region of the model parameter space from the LHC searches, strikingly, there is a region of this parameter space that is beyond the reach of the existing LHC searches, and doubly/singly charged and neutral Higgses as light as 200 GeV or even lighter are allowed by the LHC data. We study several search strategies targeting different parts of this LHC elusive parameter space at two configurations of $e^{-}{e}^{+}$ colliders—500 GeV and 1 TeV center of mass energies. We find that a vast region of this parameter space could be probed with $5\sigma$ statistical significance indicating discovery with the early $e^{-}{e}^{+}$ colliders’ data.

We present a lattice QCD study of the neutrinoless double beta decay involving light sterile neutrinos. The calculation is performed at physical pion mass using five gauge ensembles generated with $2+1$-flavor domain wall fermions. We obtain the low-energy constants $g_{\mathrm{LR}}^{\pi \pi }(m_{\nu })$ with the neutrino mass $m_{\nu }$ from 0 to 3 GeV. The lattice results are reasonably consistent with the previous interpolation method with a $\sim 20\%$ deviation at small $m_{\nu }$. We provide an explanation on the discrepancy at vanishing neutrino mass. At large $m_{\nu }$, a good consistency between our results and the previous lattice determination of $g_4^{\pi \pi }(\mu )$ is found at $\mu =m_{\nu }=3\mathrm{GeV}$.

In this work we study the $D^{*}$ and $D$ multiplicities and how they change during the hadron gas phase of heavy ion collisions. With the help of an effective Lagrangian formalism, we calculate the production and absorption cross sections of the $D^{*}$ and $D$ mesons in a hadronic medium. We compute the time evolution of the abundances and the ratio $D^{*}/D$. They are approximately constant in time. Also, assuming a Bjorken type cooling and using an empirical relation between the freeze-out temperature and the central multiplicity density, we estimate $D^{*}/D$ as a function of $dN/d\eta (\eta =0)$, which represents the system size. We find that, while the number of $D^{*}$’s and $D$’s grows significantly with the system size, their ratio remains approximately constant. This prediction can be compared with future experimental data. Our results suggest that the charm meson interactions in the hadron gas do not change their multiplicities and consequently these mesons are close to chemical equilibrium.

We perform a theoretical study of the $D_s^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}\eta$ decay. We look first at the basic $D_s^{+}$ decay at the quark level from external and internal emission. Then we hadronize a pair or two pairs of $q\overline{q}$ states to have mesons at the end. Posteriorly the pairs of mesons are allowed to undergo final state interaction, by means of which the $a_0(980)$, $f_0(980)$, $a_1(1260)$, and $b_1(1235)$ resonances are dynamically generated. The $G$ parity is used as a filter of the possible channels, and from those with negative $G$ parity only the ones that can lead to ${\pi }^{+}{\pi }^{+}{\pi }^{-}\eta$ at the final state are kept. Using transition amplitudes from the chiral unitary approach that generates these resonances and a few free parameters, we obtain a fair reproduction of the six mass distributions reported in the BESIII experiment.

We study the radiative decays $Z_c(3900)/Z_c(4020)\to \gamma {\chi }_{cJ}(\gamma {\chi }_{cJ}^{\prime })$ ($J=0$, 1, 2), with the assumption that $Z_c(3900)$ and $Z_c(4020)$ couple strongly to $D{\overline{D}}^{*}+\mathrm{c}.\mathrm{c}.$ and $D^{*}{\overline{D}}^{*}$ channels, respectively. By considering the contributions of intermediate charmed mesons triangle loops within an effective Lagrangian approach, it is shown that the calculated partial widths of $Z_c(3900)\to \gamma {\chi }_{cJ}$ are about a few hundred keV, while the obtained partial widths $Z_c(4020)\to \gamma {\chi }_{cJ}$ are about tens of keV. The predicted partial widths of $Z_c(3900)\to \gamma {\chi }_{c0,1}^{\prime }$ are less than 1 keV, which is mainly due to the very small phase space. For $Z_c(4020)\to \gamma {\chi }_{c0,2}^{\prime }$, the calculated partial widths are usually smaller than 1 keV. For the $Z_c(4020)\to \gamma {\chi }_{c1}^{\prime }$ process, the obtained partial widths can reach up to the order of 10 keV. Furthermore, the dependence of these ratios between different decay modes on the masses of $Z_c(3900)$ or $Z_c(4020)$ are also investigated, which may be a good quantity for the experiments. It is hoped that the calculations here could be tested by future experiments.

We explore consequences of the existence of gluonic hot spots inside the proton for coherent and incoherent exclusive vector meson production cross sections in deep inelastic scattering. By working in the dilute limit of the Color Glass Condensate framework to compute the cross sections for Gaussian hot spots of fluctuating color charges and employing a nonrelativistic vector meson wave function, we are able to perform large parts of the calculation analytically. We find that the coherent cross section is sensitive to both the size of the target and the structure of the probe. The incoherent cross section is dominated by color fluctuations at small transverse momentum transfer ($t$), by proton and hot spot sizes as well as the structure of the probe at medium $t$ and again by color fluctuations at large $t$. While the $t$-dependence of the cross section is well reproduced in our model, the relative normalization between the coherent and the incoherent cross sections points to the need for additional fluctuations in the proton.

A new formalism for the factorization of the cross section for single-hadron production in $e^{+}{e}^{-}$ annihilations, differential in $z_h$, $P_T$, and thrust, is applied to the phenomenological analysis of data recently measured by the BELLE Collaboration. Within this scheme the $e^{+}{e}^{-}\to hX$ cross section can be recast in the convolution of a perturbatively calculable coefficient and a universal transverse-momentum-dependent fragmentation function. While performing a next-to-leading-order calculation of the perturbative part of the process to next-to-leading logarithmic accuracy, we examine and thoroughly discuss the suitability of a number of possible Ansätze to model the nonperturbative part of this universal transverse-momentum-dependent fragmentation function, showing the extent to which present experimental data can actually constrain its shape and functional form in terms of $z_h$, $P_T$, and thrust.

We evaluate the contributions of $({\pi }^0{\pi }^0,{\pi }^0\eta ,\eta \eta )\gamma$ exclusive channels to the leading order hadronic vacuum polarization (HVP) of the muon anomalous magnetic moment. These final states can be viewed as decay subchannels in previous evaluations of the ${\pi }^0\omega ,\eta \omega$, and $\eta \varphi$ contributions to $a_{\mu }^{\mathrm{had},\mathrm{LO}}$, where the vector resonances (decaying into ${\pi }^0/\eta +\gamma$) are assumed to be on-shell. Since the separation of resonance and background contributions in a given observable is, in general, a model-dependent procedure, here we use pseudoscalar mesons and the photon as the in and out states of the $e^{+}{e}^{-}\to ({\pi }^0{\pi }^0,{\pi }^0\eta ,\eta \eta )\gamma$ $S$-matrix, such that the cross section contains the interferences among different contributions to the amplitudes. We find $a_{\mu }^{\mathrm{had},\mathrm{LO}}(P_1^0{P}_2^0\gamma )=(1.17\pm 0.13)\times {10}^{-10}$, where uncertainties stem mainly from vector meson dominance model parameters. Improved experimental studies of these exclusive channels in the whole range below 2 GeV would reduce model-dependency.

In this work, we present the computation of the one-loop electroweak radiative corrections to the scattering process $WW\to HH$ within the context of the Higgs Effective Field Theory (HEFT). We assume that the fermionic interactions are like in the Standard Model, whereas the beyond Standard Model interactions in the bosonic sector are given by the electroweak chiral Lagrangian (EChL). The computation of the one-loop amplitude and the renormalization program is performed in terms of the involved one-particle-irreducible (1PI) functions and using $R_{\xi }$ covariant gauges. The renormalization of 1PI functions at arbitrary external momenta is a more ambitious program than just renormalizing the amplitude with on-shell external legs, and it has the advantage that they can be used in several scattering amplitudes. In fact, we use here some of the 1PI functions already computed in our previous work (devoted to $WZ\to WZ$). We will complement them here with the computation of the new 1PI functions required for $WW\to HH$. From this renormalization procedure, we will also derive the full set of renormalized coefficients of the EChL that are relevant for this scattering process. In the last part, we will present the numerical results for the EChL predictions of the one-loop level cross section, $\sigma (WW\to HH){|}_{1\text{−}\mathrm{loop}}$, as a function of the center-of-mass energy, showing the relative size of the one-loop radiative corrections with respect to the tree-level prediction in terms of the EChL coefficients. The results of the one-loop corrections to $WW\to HH$ for the SM case will be also presented, for comparison with the EChL case, following the same computational method—i.e., by means of the renormalization of 1PI functions.

BDX-MINI is a beam dump experiment optimized to search for light dark matter produced in the interaction of the intense CEBAF 2.176 GeV electron beam with the Hall A beam dump at Jefferson Lab. The BDX-MINI detector consists of a ${\mathrm{PbWO}}_4$ electromagnetic calorimeter surrounded by a hermetic veto system for background rejection. The experiment accumulated $2.56\times {10}^{21}$ EOT in six months of running. Simulations of fermionic and scalar dark matter interactions with electrons of the active volume of the BDX-MINI detector were used to estimate the expected signal. Data collected during the beam-off time allowed us to characterize the background dominated by cosmic rays. A blind data analysis based on a maximum-likelihood approach was used to optimize the experiment sensitivity. An upper limit on the production of light dark matter was set using the combined event samples collected during beam-on and beam-off configurations. In some kinematic regions of interest, this pilot experiment is sensitive to the parameter space covered by some of the most sensitive experiments to date, which demonstrates the discovery potential of the next generation beam dump experiment planned at intense electron beam facilities.

The STAR Collaboration reports measurements of the transverse single-spin asymmetries, $A_N$, for inclusive jets and identified “hadrons within jets” production at midrapidity from transversely polarized $pp$ collisions at $\sqrt{s}=200\mathrm{GeV}$, based on data recorded in 2012 and 2015. The inclusive jet asymmetry measurements include $A_N$ for inclusive jets and $A_N$ for jets containing a charged pion carrying a momentum fraction $z>0.3$ of the jet momentum. The identified hadron within jet asymmetry measurements include the Collins effect for charged pions, kaons, and protons, and the Collins-like effect for charged pions. The measured asymmetries are determined for several distinct kinematic regions characterized by the jet transverse momentum $p_T$ and pseudorapidity $\eta$, as well as the hadron momentum fraction $z$ and momentum transverse to the jet axis $j_T$. These results probe higher momentum scales ($Q^2$ up to $\sim 900{\mathrm{GeV}}^2$) than current, semi-inclusive deep-inelastic scattering measurements, and they provide new constraints on quark transversity in the proton and enable tests of evolution, universality, and factorization breaking in the transverse-momentum-dependent formalism.

We present the results from combining machine learning with the profile likelihood fit procedure, using data from the Large Underground Xenon (LUX) dark matter experiment. This approach demonstrates reduction in computation time by a factor of 30 when compared with the previous approach, without loss of performance on real data. We establish its flexibility to capture nonlinear correlations between variables (such as smearing in light and charge signals due to position variation) by achieving equal performance using pulse areas with and without position-corrections applied. Its efficiency and scalability furthermore enables searching for dark matter using additional variables without significant computational burden. We demonstrate this by including a light signal pulse shape variable alongside more traditional inputs, such as light and charge signal strengths. This technique can be exploited by future dark matter experiments to make use of additional information, reduce computational resources needed for signal searches and simulations, and make inclusion of physical nuisance parameters in fits tractable.

Recently, the ModMax theory has been proposed as a unique conformal nonlinear extension of electrodynamic theories. We have shown in [H. Babaei-Aghbolagh et al., Phys. Lett. B 829, 137079 (2022).] that this modification can be reproduced by using a marginal $T\overline{T}$-like deformation from pure Maxwell theory. Further, it was shown that this deformation is solvable by applying a perturbative approach. In this paper, we will investigate a similar marginal $T\overline{T}$-like deformation for a general two-dimensional scalar field theory. It is shown that employing an irrelevant $T\overline{T}$ operator on this marginal scalar theory will produce a generalized Nambu-Goto action of this scalar theory which is a Born-Infeld-like action in two dimensions. Using a similar prescription for a two-dimensional theory with multiple scalar fields, we show that the marginal $T\overline{T}$-like deformation yields a ModMax-like Lagrangian and then the irrelevant operator produces a generalized scalar ModMax action.

The entanglement wedge cross section in holographic picture provides a geometrical description of the entanglement for mixed states. In this paper we study the inequalities for the entanglement wedge cross section in AdS/BCFT duality. In the presence of the boundary in conformal field theory (CFT), the dual entanglement wedge cross section exhibits abundant phase structures since the extremal surface may end on the brane. We present a universal treatment which is applicable for all the possible phases such that the inequalities for the entanglement wedge cross section can be proved in an algebraic manner rather than a diagrammatic manner. We show that the entanglement wedge cross section in AdS/BCFT satisfies the same inequalities as in AdS/CFT.

The classical double copy relates solutions of biadjoint, gauge, and gravity theories. The ultimate origin and scope of this correspondence remains mysterious, such that it is important to build a clear physical intuition of how the double copy operates. To this end, we consider the multipole expansion of exact classical solutions. Using a recently developed twistor translation of the classical double copy, we use well-established techniques to show that the multipole moments of arbitrary vacuum type-D gravity fields are exactly related to their counterparts in gauge and biadjoint scalar theories by the single and zeroth copies. We cross-check our results using previously obtained results for the Kerr metric and also provide new results for the “square root” of the Kerr-Taub-NUT solution.

In this work, we give two proposals regarding the status of connectivity of entanglement wedges and the associated saturation of mutual information. The first proposal has been given for the scenario before the Page time depicting the fact that at a particular value of the observer’s time $t_b=t_R$ (where $t_R\ll \beta$), the mutual information $I(R_{+}:R_{-})$ vanishes representing the disconnected phase of the radiation entanglement wedge. We argue that this time is the Hartman-Maldacena time at which the fine-grained entropy of radiation goes as $S(R)\sim \log (\beta )$, where $\beta$ is the inverse of Hawking temperature of the black hole. On the other hand, the second proposal probes the crucial role played by the mutual information of black hole subsystems in obtaining the correct Page curve of radiation.

We study thermal transitions in a domain wall AdS/QCD model. The model is based on the D5/probe D7 system with a discontinuous mass profile which restricts chiral fermions to $3+1$ dimensional domain walls. Fluctuations on the domain wall are dual to the quark mass and condensate and reveal the relation between domain wall separation and the quark mass. The massive quarks exhibit a second order thermal, meson melting transition. Witten’s multitrace prescription can be used to interpret these configurations as having a dynamical mass from a Nambu-Jona-Lasinio interaction—here the transition is first order. Confinement can be introduced into the gauge sector by compactifying one direction of the D5. Compactification induces chiral symmetry breaking and there is a first order thermal restoration transition. If a NJL interaction is also introduced then the confinement and chiral symmetry breaking scales can be separated.

Standard dilatonic supergravity $p$-branes have scalar charges that are not independent parameters but are determined by the brane tension and Page charges. This feature can be traced to the no-hair theorem in the four-dimensional Einstein-scalar gravity, implying that more general solutions with independent scalar charges can have naked singularities. Since singular branes are also of interest as tentative classical counterparts of unstable tachyonic branes and/or brane-antibrane systems, it is worth investigating branes with independent scalar charges in more detail. Here, we study singular branes associated with the Fisher-Janis-Newman-Winicour solution of four-dimensional gravity. In the case of codimension three, we also construct singular branes endowed with a Zipoy-Voorhees-type oblateness parameter. It is expected that such branes will not be supersymmetric in the string theory. We demonstrate this in the special case of NS5-branes of type II theory. We analyze geodesics and test scalar perturbations of new solutions focusing on possible quantum healing of classical singularities.

We study neutron star configurations in a simple shift-symmetric subfamily of degenerate higher-order scalar-tensor theories, whose deviations from general relativity (GR) are characterized by a single parameter. We compute the radial profiles of neutron stars in these theories of modified gravity, using several realistic equations of state for the neutron star matter. We find neutron stars with masses and radii significantly larger than their GR counterparts. We then consider slowly rotating solutions and determine the relation between the dimensionless moment of inertia and the compactness, a relation that has the property to be almost insensitive to the equation of state.