We present numerical studies of the leading nonlinear corrections to the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations of parton distribution functions (PDFs) resulting from gluon recombination. The effect of these corrections is to reduce the pace of evolution at small momentum fractions $x$ while slightly increasing it at intermediate $x$. By implementing the nonlinear evolution in the xfitter framework, we have carried out fits of proton PDFs using data on lepton-proton deep inelastic scattering from HERA, BCDMS, and NMC. While we find no evidence for the presence of nonlinearities, they cannot be entirely excluded either, and we are able to set limits for their strength. In terms of the recombination scale $Q_r$, which plays a similar role as the saturation scale in the dipole picture of the proton, we find that $Q_r\lesssim 2.5\mathrm{GeV}$. We also quantify the impact of the nonlinear terms for the longitudinal structure function at the Electron-Ion Collider and the Large Hadron Electron Collider and find that these measurements could provide stronger constraints on the projected effects.

We consider birefringent (i.e., polarization changing) scattering of x-ray photons at the superposition of two optical laser beams of ultrahigh intensity and study the resonant contributions of axions or axionlike particles, which could also be short lived. Applying the specifications of the Helmholtz International Beamline for Extreme Fields (HIBEF), we find that this setup can be more sensitive than previous light-by-light scattering (birefringence) or light-shining-through-wall experiments in a certain domain of parameter space. By changing the pump and probe laser orientations and frequencies, one can even scan different axion masses, i.e., chart the axion propagator.

We provide a first quantitative indication that the wave function of the proton contains unequal distributions of charm quarks and antiquarks, i.e., a nonvanishing intrinsic valence charm distribution. A significant nonvanishing valence component cannot be perturbatively generated; hence, our results reinforce previous evidence that the proton contains an intrinsic (i.e., not radiatively generated) charm quark component. We establish our result through a determination of the parton distribution functions of charm quarks and antiquarks in the proton. We propose two novel experimental probes of this intrinsic charm valence component: $D$-meson asymmetries in $Z+c$-jet production at the LHCb experiment and flavor-tagged structure functions at the Electron-Ion Collider.

Despite remarkable success in describing supergravity reductions and backgrounds, generalized geometry and exceptional field theory are still lacking a fundamental object of differential geometry, the Riemann tensor. We show that to construct it, a hierarchy of connections is required. They complement the spin connection with higher representations known from the tensor hierarchy. This approach allows to define generalized homogeneous spaces which underlie generalized U-duality, admit consistent truncations and provide a huge class of new flux backgrounds with nontrivial structure groups.

We propose the stringy description of the system consisting of two heavy and four light quarks in the case of two light flavors of equal mass. As an application, we consider the three low-lying Born-Oppenheimer potentials as a function of the heavy quark separation. Our analysis shows that the ground state potential is described in terms of both hadroquarkonia and hadronic molecules. A connected string configuration makes the dominant contribution to the potential of an excited state at small separations, and for separations larger than 0.1 fm, it exhibits the diquark-diquark-diquark structure $[Qq][Qq][qq]$. For better understanding the quark organization inside the system, we introduce several critical separations related to the processes of string reconnection, breaking and junction annihilation. We also discuss the simplest string configurations including the five-string junctions and their implications for the system, in particular the emergence of composite quark objects different from diquarks and the process of junction fusion.

We study the Sachdev-Ye-Kitaev (SYK) model—an important toy model for quantum gravity on IBM’s superconducting qubit quantum computers. By using a graph-coloring algorithm to minimize the number of commuting clusters of terms in the qubitized Hamiltonian, we find the gate complexity of the time evolution using the first-order product formula for $N$ Majorana fermions is $\mathcal{O}(N^5{J}^2{t}^2/\epsilon )$ where $J$ is the dimensionful coupling parameter, $t$ is the evolution time, and $\epsilon$ is the desired precision. With this improved resource requirement, we perform the time evolution for $N=6$, 8 with maximum two-qubit circuit depth and gate count of 343. We perform different error mitigation schemes on the noisy hardware results and find good agreement with the exact diagonalization results on classical computers and noiseless simulators. In particular, we compute vacuum return probability after time $t$ and out-of-time order correlators which is a standard observable of quantifying the chaotic nature of quantum systems.

We construct the hydrodynamic expansion for a rotating and accelerated medium in a curved space-time, and establish the relationship between the currents generated by the cosmological constant and the acceleration. Then we consider the more general case with a nonzero Weyl tensor, and show the duality between the current in flat space-time and the gravitational axial anomaly. This generalizes the previous derivation to the case with a nonzero Ricci tensor.

We present a new method and implementation to obtain Bayesian posteriors on the amplitude parameters $\{h_0,\cos \iota ,\psi ,{\varphi }_0\}$ of continuous gravitational waves emitted by known pulsars. This approach leverages the well-established $\mathcal{F}$-statistic framework and software. We further explore the benefits of employing a likelihood function that is analytically marginalized over ${\varphi }_0$, which avoids signal degeneracy problems in the $\psi \text{−}{\varphi }_0$ subspace. The method is tested on simulated signals, hardware injections in Advanced-LIGO detector data, and by performing percentile-percentile self-consistency tests of the posteriors via Monte-Carlo simulations. We apply our methodology to PSR J1526-2744, a recently discovered millisecond pulsar. We find no evidence for a signal and obtain a Bayesian upper limit $h_0^{95\%}$ on the gravitational-wave amplitude of approximately $7\times {10}^{-27}$, comparable with a previous frequentist upper limit.

The statistical mechanics of an ideal gas of point particles moving in a time independent background metric with $g_{0j}\ne 0$ is investigated. An explicit calculation shows that when there is no background electrostatic or magnetostatic field the thermodynamic pressure, energy density, and thermally averaged energy-momentum tensor depend on temperature and chemical potential only through the ratios $T_0/\sqrt{g_{00}}$ and ${\mu }_0/\sqrt{g_{00}}$. A background magnetostatic field does not change this, however with a background electrostatic field the previous results are multiplied by a factor $\exp (-e{A}_0/T_0)$, which is an exception to the strict Tolman-Ehrenfest rule because the system is open.

We highlight the role of weak lensing measurements from current and upcoming stage-IV imaging surveys in the search for cosmic inflation, specifically in measuring the scalar spectral index $n_s$. To do so, we combine the Dark Energy Survey 3 years of observation weak lensing and clustering data with Bicep/Keck, Planck, and Sloan Digital Sky Survey data in $r\mathrm{\Lambda }\mathrm{CDM}$ (cold dark matter) where $r$ is the tensor-to-scalar ratio. While there is no significant improvement in constraining power, we obtain a $1\sigma$ shift on $n_s$. Additionally, we forecast a weak lensing and clustering data vector from the 10-year Legacy Survey of Space and Time by the Vera C. Rubin Observatory and show its combination with current data would improve their $n_s$ constraints by 25% in $r\mathrm{\Lambda }\mathrm{CDM}$.

We present an analytic model of nonlinear correlators of galaxy/halo ellipticities in redshift space. The three-dimensional ellipticity field is not affected by the redshift-space distortion (RSD) at linear order, but by the nonlinear one, known as the Finger-of-God effect, caused by the coordinate transformation from real to redshift space. Adopting a simple Gaussian damping function to describe the nonlinear RSD effect and the nonlinear alignment model for the relation between the observed ellipticity and underlying tidal fields, we derive analytic formulas for the multipole moments of the power spectra of the ellipticity field in redshift space expanded in not only the associated Legendre basis, a natural basis for the projected galaxy shape field, but also the standard Legendre basis, conventionally used in literature. The multipoles of the corresponding correlation functions of the galaxy shape field are shown to be expressed by a simple Hankel transform, as is the case for those of the conventional galaxy density correlations. We measure these multipoles of the power spectra and correlation functions of the halo ellipticity field using large-volume $N$-body simulations. We then show that the measured alignment signals can be better predicted by our nonlinear model than the existing linear alignment model. The formulas derived here have already been used to place cosmological constraints using from the redshift-space correlation functions of the galaxy shape field measured from the Sloan Digital Sky Survey [T. Okumura and A. Taruya, Astrophys. J. Lett. 945, L30 (2023).].

We investigate the effects on sub-TeV resonant leptogenesis of primordial black holes with masses from ${10}^6\mathrm{g}$ to $\sim {10}^9\mathrm{g}$. The latter might dominate the energy content of the Universe altering its evolution and, eventually, diluting the final baryon asymmetry. We find that, depending on the mass and abundance of primordial black holes, the parameter space of sub-TeV resonant leptogenesis shrinks towards higher right-handed neutrino masses and smaller active-sterile mixing. Remarkably, this translates into important implications for the experimental searches of heavy neutral leptons. Conversely, we demonstrate that a possible future detection of sub-TeV heavy neutral leptons would disfavor regions of the parameter space of primordial black holes currently allowed.

We conduct a combined analysis to investigate dark matter (DM) with hypercharge anapole moments, focusing on scenarios where Majorana DM particles with spin $1/2$, 1, $3/2$, and 2 interact exclusively with Standard Model particles through ${\mathrm{U}(1)}_Y$ hypercharge anapole terms for the first time. For completeness, we construct general effective U(1) gauge-invariant three-point vertices. These enable the generation of hypercharge gauge-invariant interaction vertices for both a virtual photon $\gamma$ and a virtual $Z$ boson with two identical massive Majorana particles of any nonzero spin $s$, after the spontaneous breaking of electroweak gauge symmetry. For complementarity, we adopt effective operators tailored to each dark matter spin allowing crossing symmetry. We calculate the relic abundance, analyze current constraints and future sensitivities from dark matter direct detection and collider experiments, and apply the conceptual naive perturbativity bound. Our estimations based on a generalized vertex calculation demonstrate that the scenario with a higher-spin DM is more stringently constrained than a lower-spin DM, primarily due to the reduced annihilation cross section and/or the enhanced rate of LHC monojet events. As a remarkable outcome, the spin-2 anapole DM scenario is almost entirely excluded, while the high-luminosity LHC exhibits high sensitivities in probing spin-1 and -$3/2$ scenarios, except for a tiny parameter range of DM mass around 1 TeV. A significant portion of the remaining parameter space in the spin-$1/2$ DM scenario can be explored through upcoming Xenon experiments, with more than 20 ton-yr exposure equivalent to approximately 5 years of running the XENONnT experiment.

Current measurements of the $h\to Z\gamma$ signal strength invite us to speculate about possible new physics interactions that exclusively affect ${\mu }_{Z\gamma }$ without altering the other signal strengths. Additional consideration of tree unitarity enables us to correlate the nonstandard values of ${\mu }_{Z\gamma }$ with an upper limit on the scale of new physics. We find that even when ${\mu }_{Z\gamma }$ deviates from the Standard Model value by only 20%, the scale of new physics should be well within the reach of the LHC.

The natural grand unified theories (GUT) solve various problems of the supersymmetric GUT and give realistic quark and lepton mass matrices under the natural assumption that all terms allowed by the symmetry are introduced with $O(1)$ coefficients. However, because of the natural assumption, it is difficult to achieve the gauge coupling unification without tuning, while keeping neutrino masses at realistic values. In this paper, we try to avoid this tension between the neutrino masses and the gauge coupling unification, by introducing suppression factors for several terms. These suppression factors can be understood by approximate symmetries in some of the solutions. We show that one of the most important results in the natural GUT scenario, that the nucleon decay mediated by superheavy gauge fields is enhanced due to a smaller unification scale while the nucleon decay mediated by superheavy colored Higgs is suppressed, may change in those models proposed in this paper.

In the present work, we investigate the production of the newly observed $P_{\psi s}^{\mathrm{\Lambda }}(4338)$ state in ${\mathrm{\Xi }}_b^{-}$ decay, where the $P_{\psi s}^{\mathrm{\Lambda }}(4338)$ is assigned as a ${\mathrm{\Xi }}_c\overline{D}$ molecular state. By using an effective Lagrangian approach, we evaluate the branching fractions of ${\mathrm{\Xi }}_b^{-}\to P_{\psi s}^{\mathrm{\Lambda }}(4338)K^{-}$ via the triangle loop mechanism. The branching fractions of ${\mathrm{\Xi }}_b^{-}\to P_{\psi s}^{\mathrm{\Lambda }}(4338)K^{-}$ are in the order of ${10}^{-4}$; the result is compared with our previous work of ${\mathrm{\Xi }}_b^{-}\to P_{\psi s}^{\mathrm{\Lambda }}(4459)K^{-}$. We also predict the ratio of $P_{\psi s}^{\mathrm{\Lambda }}(4459)$ and $P_{\psi s}^{\mathrm{\Lambda }}(4338)$ productions in the decay ${\mathrm{\Xi }}_b^{-}\to P_{\psi s}^{\mathrm{\Lambda }}{K}^{-}\to J/\psi \mathrm{\Lambda }{K}^{-}$. The predicted branching fractions and their ratios could be tested experimentally, which may be helpful for understanding the molecular picture of $P_{\psi s}^{\mathrm{\Lambda }}(4338)$ as well as other hidden-charm pentaquark states with strangeness. Moreover, the experimental potential of observing $P_{\psi s}^{\mathrm{\Lambda }}(4338)$ in the ${\mathrm{\Xi }}_b^{-}\to K^{-}J/\psi \mathrm{\Lambda }$ is discussed.

We investigate the role of the electromagnetic interaction in the formation and decay of the $X(3872)$. The binding properties of the $X(3872)$ are studied by assuming the molecular nature and considering the $S\text{−}D$ wave mixing, isospin breaking, and coupled channel effects, and in particular the correction from the electromagnetic interaction. The radiative decays can better reflect the difference between the charged and neutral $D{\overline{D}}^{*}$ components, since the electromagnetic interaction explicitly breaks the isospin symmetry. We further study the radiative decay widths with the obtained wave functions for different $D{\overline{D}}^{*}$ channels. We also explore other similar hidden-charm molecular states. The electromagnetic interaction can make the molecule tighter. Our result of the radiative decay width for $X(3872)\to \gamma J/\psi$ is in agreement with the experiment. The branching ratio $R_{\gamma \psi }$ is less than 1 in our framework, which supports the Belle and BESIII measurements.

In this article we analyze the inclusive photoproduction of heavy charmonia-bottomonia pairs in the color glass condensate framework and demonstrate that the cross section of the process is sensitive to dipole and quadrupole forward scattering amplitudes (2- and 4-point correlators of Wilson lines). Using the phenomenological parametrizations of these amplitudes, we estimate numerically the production cross sections in the kinematics of the forthcoming Electron Ion Collider and the ultraperipheral collisions at the LHC. We found that the contribution controlled by the quadrupole amplitude is dominant, and for this reason, the suggested channel can be used as a gateway for studies of this nonperturbative object.

We discuss a novel effective-field-theory-based approach for extracting two-body scattering information from finite volume energies, serving as an alternative to Lüscher’s method. By explicitly incorporating one-pion exchange, we overcome the challenging left-hand cut problem in Lüscher’s method and can handle finite volume energy levels both below and above the left-hand cut. Applied to the lattice data for $D{D}^{*}$ scattering at a pion mass of 280 MeV, as an illustrative example, our results reveal the significant impact of the one-pion exchange on $P$-wave and $S$-wave phase shifts. The pole position of the $T_{cc}(3875{)}^{+}$ state, extracted from the finite-volume energy levels at this pion mass while taking into account left-hand cut effects, range corrections and partial-wave mixing, is consistent with a near-threshold resonance. This study demonstrates, for the first time, that two-body scattering information can be reliably extracted from lattice spectra including the left-hand cut.

Using $e^{+}{e}^{-}$ collision data collected with the BESIII detector operating at the BEPCII collider, the Born cross sections of $e^{+}{e}^{-}\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c(2595{)}^{-}+\mathrm{c}.\mathrm{c}.$ and $e^{+}{e}^{-}\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c(2625{)}^{-}+\mathrm{c}.\mathrm{c}.$ are measured for the first time at center-of-mass energies of $\sqrt{s}=4918.0$ and 4950.9 MeV. Nonzero cross sections are observed very close to the production threshold. The measured Born cross sections of $e^{+}{e}^{-}\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c(2625{)}^{-}+\mathrm{c}.\mathrm{c}.$ are about 2–3 times greater than those of $e^{+}{e}^{-}\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c(2595{)}^{-}+\mathrm{c}.\mathrm{c}.$, providing the similar behavior as semileptonic decays of ${\mathrm{\Lambda }}_b^0$, but different behavior from that in the hadronic decays of ${\mathrm{\Lambda }}_b^0$. The Born cross sections are $15.6\pm 3.1\pm 0.9\mathrm{pb}$ and $29.4\pm 3.7\pm 2.7\mathrm{pb}$ for $e^{+}{e}^{-}\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c(2595{)}^{-}+\mathrm{c}.\mathrm{c}.$, and are $43.4\pm 4.0\pm 4.1\mathrm{pb}$ and $76.8\pm 6.5\pm 4.2\mathrm{pb}$ for $e^{+}{e}^{-}\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c(2625{)}^{-}+\mathrm{c}.\mathrm{c}.$ at $\sqrt{s}=4918.0$ and 4950.9 MeV, respectively. Based on the polar angle distributions of the ${\overline{\mathrm{\Lambda }}}_c(2625{)}^{-}$ and ${\mathrm{\Lambda }}_c(2625{)}^{+}$, the form-factor ratios $\sqrt{|G_E{|}^2+3|G_M{|}^2}/|G_C|$ are determined for $e^{+}{e}^{-}\to {\mathrm{\Lambda }}_c^{+}{\overline{\mathrm{\Lambda }}}_c(2625{)}^{-}+\mathrm{c}.\mathrm{c}.$ for the first time, which are $5.95\pm 4.07\pm 0.15$ and $0.94\pm 0.32\pm 0.02$ at $\sqrt{s}=4918.0$ and 4950.9 MeV, respectively. All of these first uncertainties are statistical and second systematic.