Multiflavor gauge theories of matter systems on a three-dimensional lattice have recently been widely investigated especially in connection with a possible symmetry enlargement at a continuous phase transition. Abelian models were studied both with compact gauge fields and in a mixed formulation in which the coupling with matter fields is in compact form while the gauge fields Lagrangian is written in terms of noncompact gauge fields, getting quite different results. Such a mixed formulation is not permissible for non-Abelian theories, for which however there exists an entirely noncompact formulation (in which exact gauge invariance is enforced by help of auxiliary fields), which for SU(2) was shown to yield in the scaling window a larger physical volume than Wilson’s one. The corresponding U(1) noncompact regularization is derived in the present work. In both Abelian and SU(2) cases there is only one auxiliary field that for a large mass has a linear coupling with the other fields and it can be integrated out yielding a negative definite correction. The coupling with the auxiliary field might make the inversion of the fermion matrix easier.

We introduce a simple lattice spin model that is written in terms of the well-known four-dimensional $\gamma$-matrix representation of the Clifford algebra. The local spins with a four-dimensional Hilbert space transform in a spinorial $(1/2,0)\oplus (0,1/2)$ representation of SO(4), a symmetry of our model. When studied on a chain, and as a function of a transverse field tuning parameter, our model undergoes a quantum phase transition from a valence bond solid phase to a critical phase that is described by an $\mathrm{SU}(2{)}_1$ Wess-Zumino-Witten field theory.

We discuss the reactions $\pi p\to \pi p$ and $\pi p\to \pi p\gamma$ from a general quantum field theory (QFT) point of view, describing these reactions in QCD and lowest relevant order of electromagnetism. We consider the pion-proton elastic scattering both off shell and on shell. The on-shell amplitudes for ${\pi }^{\pm }p\to {\pi }^{\pm }p$ scattering are described by two invariant amplitudes, while the off-shell amplitudes contain eight invariant amplitudes. We study the photon emission amplitudes in the soft-photon limit where the center-of-mass photon energy $\omega \to 0$. The Laurent expansion in $\omega$ of the ${\pi }^{\pm }p\to {\pi }^{\pm }p\gamma$ amplitudes is considered and the terms of the orders ${\omega }^{-1}$ and ${\omega }^0$ are derived. These terms can be expressed by the on-shell invariant amplitudes and their partial derivatives with respect to $s$ and $t$. The pole term $\propto {\omega }^{-1}$ in the amplitudes corresponds to Weinberg’s soft-photon theorem and is well known from the literature. We derive the next-to-leading term $\propto {\omega }^0$ using only rigorous methods of QFT. We give the relation of the Laurent series for ${\pi }^{0}p\to {\pi }^{0}p\gamma$ and Low’s soft-photon theorem. Our formulas for the amplitudes in the limit $\omega \to 0$ are valid for photon momentum $k$ satisfying $k^2\ge 0$, $k^0=\omega \ge 0$, that is, for both real and virtual photons. Here we consider a limit where with $\omega \to 0$ we have also $k^2\to 0$. We discuss the behavior of the corresponding cross sections for ${\pi }^{-}p\to {\pi }^{-}p\gamma$ with respect to $\omega$ for $\omega \to 0$. We consider cross sections for unpolarized as well as polarized protons in the initial and final states.

We point out a very simple method for calculating the mixed Coulomb-nuclear corrections to the $pp$ and $\overline{p}p$ scattering amplitudes that has been missed in the extensive past work on this problem. The method expresses the correction in terms of a rapidly convergent integral involving the inverse Fourier-Bessel transform of the nuclear amplitude and a known factor containing the Coulomb phase shift with form-factor corrections. The transform can be calculated analytically for the exponential-type model nuclear amplitudes commonly used in fits to the high-energy data at small momentum transfers, and gives very accurate results for the corrections. We examine the possible effects of the Martin zero in the real part of the nuclear amplitude, and the accuracy of the Bethe-West-Yennie phase approximation for the Coulomb-nuclear corrections. We then apply the method to a redetermination of the ratio $\rho$ of the real to the imaginary parts of the forward scattering amplitude in fits to high-energy Intersecting Storage Rings data previously analyzed using the approximate West-Yennie version of the correction. The only significant changes relative the accuracy of those fits are at 52.8 GeV. Our method is applicable more generally, and can be used also at lower energies and for proton-nucleus scattering.

ProtoDUNE Single-Phase (ProtoDUNE-SP) is a 770-ton liquid argon time projection chamber that operated in a hadron test beam at the CERN Neutrino Platform in 2018. We present a measurement of the total inelastic cross section of charged kaons on argon as a function of kaon energy using 6 and $7\mathrm{GeV}/c$ beam momentum settings. The flux-weighted average of the extracted inelastic cross section at each beam momentum setting was measured to be $380\pm 26\mathrm{mbarns}$ for the $6\mathrm{GeV}/c$ setting and $379\pm 35\mathrm{mbarns}$ for the $7\mathrm{GeV}/c$ setting.

We present a deep learning-based method for estimating the neutrino energy of charged-current neutrino-argon interactions. We employ a recurrent neural network (RNN) architecture for neutrino energy estimation in the MicroBooNE experiment, utilizing liquid argon time projection chamber (LArTPC) detector technology. Traditional energy estimation approaches in LArTPCs, which largely rely on reconstructing and summing visible energies, often experience sizable biases and resolution smearing because of the complex nature of neutrino interactions and the detector response. The estimation of neutrino energy can be improved after considering the kinematics information of reconstructed final-state particles. Utilizing kinematic information of reconstructed particles, the deep learning-based approach shows improved resolution and reduced bias for the muon neutrino Monte Carlo simulation sample compared to the traditional approach. In order to address the common concern about the effectiveness of this method on experimental data, the RNN-based energy estimator is further examined and validated with dedicated data-simulation consistency tests using MicroBooNE data. We also assess its potential impact on a neutrino oscillation study after accounting for all statistical and systematic uncertainties and show that it enhances physics sensitivity. This method has good potential to improve the performance of other physics analyses.

We provide supporting details for the search for a $3+1$ sterile neutrino using data collected over 10.7 years at the IceCube Neutrino Observatory. The analysis uses atmospheric muon-flavored neutrinos from 0.5 to 100 TeV that traverse Earth to reach the IceCube detector and finds a best-fit point at ${\sin }^2(2{\theta }_{24})=0.16$ and $\mathrm{\Delta }{m}_{41}^2=3.5{\mathrm{eV}}^2$ with a goodness-of-fit p value of 12% and consistency with the null hypothesis of no oscillations to sterile neutrinos with a p value of 3.1%. Several improvements were made over past analyses, which are reviewed in this article, including upgrades to the reconstruction and the study of sources of systematic uncertainty. We provide details of the fit quality and discuss stability tests that split the data for separate samples, comparing results. We find that the fits are consistent between split datasets.

We combine techniques from kinetic theory and string dualities to couple statistical matter to a nonrelativistic supergravity background, enabling the theory to be formulated in a T-duality invariant form. Similarly to the relativistic case, we explicitly demonstrate that, in the nonrelativistic limit, the many-strings system necessitates a viscous fluid description for describing the statistical matter. This is achieved coupling a generalized energy-momentum tensor in the framework of double field theory, which it is covariant under T-duality transformations.

We introduce a field-theory framework in which fields transform under the little group, rather than the Lorentz group, specific to each particle type. By utilizing these fields, along with spinor products and the $x$ factor, we construct a field-theory action that naturally reproduces the vertices of the constructive standard model (CSM). This approach eliminates unphysical components, significantly reduces the degrees of freedom compared to traditional field theory, and offers deeper insights into the power of constructive amplitudes. Our action is momentum-conserving, Lorentz-invariant, Hermitian, and nonlocal. We also discuss this as a framework for developing new constructive field theories, discussing their essential properties and potential applicability in renormalization theory and nonperturbative calculations.

The gravitational lensing signal from the cosmic microwave background (CMB) is highly valuable to constrain the growth of the structures in the Universe in a clean and robust manner over a wide range of redshifts. One of the theoretical systematics for lensing reconstruction is the impact of the lensing field non-Gaussianities on its estimators. Nonlinear matter clustering and post-Born lensing corrections are known to bias standard quadratic estimators to some extent, most significantly so in temperature. In this work, we explore the impact of non-Gaussian deflections on maximum a posteriori lensing estimators, which, in contrast to quadratic estimators, are able to provide optimal measurements of the lensing field. We show that these naturally reduce the induced non-Gaussian bias and lead to unbiased cosmological constraints in $\mathrm{\Lambda }$ cold dark matter at CMB-S4 noise levels without the need for explicit modeling. We also test the impact of assuming a non-Gaussian prior for the reconstruction; this mitigates the effect further slightly, but generally has little impact on the quality of the reconstruction. This shows that higher-order statistics of the lensing deflections are not expected to present a major challenge for optimal CMB lensing reconstruction in the foreseeable future.

A detection of the 21-cm signal can provide a unique window of opportunity for uncovering complex astrophysical phenomena at the epoch of reionization and placing constraints on cosmology at high redshifts, which are usually elusive to large-scale structure surveys. In this work, we provide a theoretical model based on a quadratic bias expansion capable of recovering the 21-cm power spectrum with high accuracy sufficient for upcoming ground-based radio interferometer experiments. In particular, we develop a hybrid effective field theory model in redshift space that leverages the accuracy of $N$-body simulations with the predictive power of analytical bias expansion models, and test it against the Thesan suite of radiative transfer hydrodynamical simulations. We make predictions of the 21-cm brightness temperature field at several distinct redshifts, ranging between $z=6.5$ and 11, thus probing a large fraction of the reionization history of the Universe ($x_{\mathrm{HI}}=0.3\sim 0.9$), and compare our model to the “true” 21-cm brightness in terms of the correlation coefficient, power spectrum and modeling error. In practice, we use the neutral hydrogen field as a proxy for the 21-cm emission field, which in the $z\lesssim 10$ redshift range and for standard reionization is an excellent approximation. We find percent-level agreement at large and intermediate scales, $k\lesssim 0.5h/\mathrm{Mpc}$, and favorable behavior down to small scales, $k\sim 1h/\mathrm{Mpc}$, outperforming pure perturbation-theory-based models. To put our findings into context, we show that even in the absence of any foreground contamination the thermal noise of a futuristic HERA-like experiment is comparable with the theoretical uncertainty in our model in the allowed “wedge” of observations, providing further evidence in support of using hybrid-effective-field-theory-based models to approximate a range of cosmological observables.

We investigate the tensor clustering fossils as a possible probe to constrain the theory of gravity, in particular the deviation of the sound speed of gravitational waves from the speed of light at high redshifts. We develop the formalism of the effective Poisson equation to include the novel phenomenological model of the scalar-tensor tidal interactions that are expected to be induced by the modification of the theory of gravity. We show that the tensor clustering fossils can arise from the propagation of gravitational waves, the growth of the large-scale structures, and the second-order contributions from the effective Poisson equation. We construct the small-scale effective Lagrangian from the Horndeski scalar-tensor theory and derive the formula applicable to the tensor clustering fossils in the language of the effective field theory of dark energy. As a demonstration, we apply the formalism to the constraint on the sound speed of gravitational waves in the futuristic survey.

A Bose star passing through cold molecular clouds may capture atoms, molecules, and dust particles. The observational signature of such an event would be a relatively small amount of matter that is gravitationally bound. This binding may actually be provided by invisible dark matter forming the Bose star. We may expect a relative excess of heavier atoms, molecules, and solid dust compared to the content of giant cold molecular clouds since the velocity of heavy particles at a given temperature is lower and it may be small compared to the escape velocity, $v_{\mathrm{rms}}=\sqrt{3k_{\mathrm{B}}T/m_{\mathrm{gas}}}\ll v_{\mathrm{esc}}=\sqrt{2GM/R}$. Finally, the velocity of this captured matter cloud may correlate with the expected velocity of free dark matter particles (e.g., expected axion wind velocity relative to Earth).

Two out of three phase boundaries of the $1+1$-dimensional Gross-Neveu model in the chiral limit can be obtained from a standard, perturbative stability analysis of the homogeneous phases. The third one separating the massive homogeneous phase from the kink crystal is nonperturbative and could so far only be inferred from the full solution of the model. We show that this phase boundary can also be obtained via a modified stability analysis, based on the thermodynamic potential of a single kink or baryon. The same method works for the massive Gross-Neveu model, so that all phase boundaries of the Gross-Neveu model could have been predicted quantitatively without prior knowledge of the full crystal solution.

We study the effect of a varying pion mass on the quantum chromodynamics (QCD) phase diagram in the presence of an external magnetic field, aiming to understand it, for the first time, using Nambu–Jona-Lasinio like effective models. We compare results from both its local and nonlocal versions. In both cases, we find that the inverse magnetic catalysis (IMC) near the crossover is eliminated with increasing pion mass, while the decreasing trend of crossover temperature with increasing magnetic field persists for pion mass values at least up to 440 MeV. Thus, the models are capable of capturing qualitatively the results found by lattice QCD (LQCD) for heavy (unphysical) pions. The key feature in the models is the incorporation of the effect of a reduction in the coupling constant with increasing energy. Along with reproducing the IMC effect, it enables models to describe the effects of heavier current quark masses without introducing additional parameters. For the local NJL model, this agreement depends on how the parameters of the model are fit at the physical point. In this respect, the nonlocal version, which, due to its formulation, automatically exhibits the IMC effect around the crossover region, captures the physics more naturally. We further use the nonlocal framework to determine the pion mass beyond which the IMC effect around the transition region does not exist anymore.

We propose a scalar dark matter model featuring a hidden gauge symmetry, denoted as $\mathrm{U}(1{)}_{\mathrm{X}}$, with two complex scalars, $\mathrm{\Phi }$ and $S$. In this framework, $\mathrm{\Phi }$ spontaneously breaks the $\mathrm{U}(1{)}_{\mathrm{X}}$ gauge symmetry while $S$ serves as a viable dark matter candidate. Particularly, the kinetic and direct mixings between the $\mathrm{U}(1{)}_{\mathrm{X}}$ and $\mathrm{U}(1{)}_{\mathrm{Y}}$ gauge groups provide a portal between dark matter and the Standard Model particles. These mixings offer a plausible explanation for the W boson mass anomaly observed by the Collider Detector at Fermilab Collaboration. We study the comprehensive phenomenological constraints of this model from colliders and dark matter detection experiments, including $Z^{\prime }$ searches at the LHC, the 125 GeV Higgs boson measurements, the relic density of dark matter, and the indirect detection of dark matter annihilation. By randomly scanning the parameter space, we find that the regions where $m_{Z^{\prime }}\gtrsim 4750\mathrm{GeV}$ and $m_{Z^{\prime }}\lesssim 4750\mathrm{GeV}$ for $g_x$ close to 1 remain viable and can be tested by future experiments.

Neutrinos are the most elusive particles of the Standard Model. The physics behind their masses remains unknown and requires introducing new particles and interactions. An elegant solution to this problem is provided by the seesaw mechanism. Typically considered at a high scale, it is potentially testable in gravitational wave experiments by searching for a spectrum from cosmic strings, which offers a rather generic signature across many high-scale seesaw models. Here we consider the possibility of a low-scale seesaw mechanism at the PeV scale, generating neutrino masses within the framework of a model with gauged U(1) lepton number. In this case, the gravitational wave signal at high frequencies arises from a first order phase transition in the early Universe, whereas at low frequencies it is generated by domain wall annihilation, leading to a double-peaked structure in the gravitational wave spectrum. The signals discussed here can be searched for in upcoming experiments, including gravitational wave interferometers, pulsar timing arrays, and astrometry observations.

The Gribov-Zwanziger scenario attributes the phenomenon of confinement to the instantaneous interaction term in the QCD Hamiltonian in the Coulomb gauge. For a static quark-antiquark pair, it leads to a potential energy that increases linearly with the distance between them. Lattice studies of the SU(2) Yang-Mills theory determined the corresponding (Coulomb) string tension for sources in the fundamental representation, ${\sigma }_C$, to be about 3 times larger than the Wilson loop string tension, ${\sigma }_F$. It is far above the Zwanziger variational bound, ${\sigma }_C\ge {\sigma }_F$. We argue that the value often reported in the literature is artificially inflated. We examine the lattice definition of the instantaneous potential, find the source of the string tension’s enhancement, and perform its improved determination in SU(2) lattice gauge theory. We report our conservative estimate for the value of the Coulomb string tension as ${\sigma }_C/{\sigma }_F=2.0\pm 0.4$ and discuss its phenomenological implications.

We calculate the production and polarization of direct $J/\psi$ in the improved color evaporation model in $e+p$ photoproduction. We present the production as functions of transverse momentum, mass of the hadronic final state, and inelasticity. We also present the polarization parameters ${\lambda }_{\vartheta }$, ${\lambda }_{\phi }$, and ${\lambda }_{\vartheta \phi }$ in the helicity and the Collins-Soper frames, as well as the frame-invariant polarization parameter $\tilde{\lambda }$ as a function of transverse momentum and inelasticity. We find agreement with both $J/\psi$ unpolarized cross sections and the invariant polarization parameters as a function of $p_T$.