Mon·Jan 15, 2024Monday·January 15, 2024

1. 01*

   SIDIS at small $x$ at next-to-leading order: gluon contribution

   Filip Bergabo🇺🇸 · Jamal Jalilian-Marian🇺🇸

   We calculate the contribution of gluons to single inclusive hadron production at next-to-leading order (NLO) accuracy in Deep Inelastic Scattering (DIS) at small $x$ using the Color Glass Condensate formalism. It is shown that the only divergence present is the standard collinear divergence which is absorbed into evolution of gluon-hadron fragmentation function. Our calculations are performed at finite $N_c$ and we provide general finite $N_c$ expressions for the structure of Wilson lines appearing in inclusive dihadron and single hadron production cross sections. We also comment on how one can obtain rapidity distribution of hadron multiplicities from our results.

   hep-phnucl-exnucl-thPRD(2024)·15 citations
2. 02*

   Updated analysis of $D\to PP,VP$ and $VV$ decays: Implications for $K_S^0-K_L^0$ asymmetries and $D^0$-${\overline{D}}^0$ mixing

   Hai-Yang Cheng🇹🇼 · Cheng-Wei Chiang🇹🇼

   An updated analysis of the two-body $D\to PP,VP$ and $VV$ decays within the framework of the topological diagram approach is performed. A global fit to the Cabibbo-favored (CF) modes in the $VP$ sector gives many solutions with similarly small local minima in ${\chi }^2$. The solution degeneracy is lifted once we use them to predict for the singly Cabibbo-suppressed (SCS) modes. Topological amplitudes are extracted for the $\eta -{\eta }^{\prime }$ mixing angles $\varphi =40.4^{\circ }$ and $43.5^{\circ }$. The $K_S^0-K_L^0$ asymmetries in $D\to K_{S,L}^{0}M$ decays denoted by $R(D,M)$ are studied. While the predicted $R(D^0,P)$ for $P={\pi }^0,\eta$ and ${\eta }^{\prime }$ agree with experiment, the calculated $R(D^{+},{\pi }^{+})$, $R(D_s^{+},K^{+})$, $R(D^0,\omega )$ and $R(D^0,\varphi )$ deviate from the data. We conjecture that the relative phase between the topological amplitudes $(C+A)$ and $(T+C)$ should be slightly smaller than $90^{\circ }$ in order to explain the first two discrepancies and that additional singlet contributions due to the SU(3)-singlet nature of $\omega$ and $\varphi$ are needed to account for the last two. For doubly Cabibbo-suppressed (DCS) $D\to VP$ decays, their topological amplitudes (double-primed) cannot be all the same as the corresponding ones in the CF modes. The assumption of $E_{V,P}^{\prime \prime }=E_{V,P}$ for the $W$-exchange amplitude leads to some inconsistencies with the experiment. Through the measured relative phases between CF and DCS channels, the relations of $E_{V,P}^{\prime \prime }$ with $E_{V,P}$ are determined. Long-distance contributions to the $D^0$-${\overline{D}}^0$ mixing parameter $y$ are evaluated in the exclusive approach. In particular, we focus on $D\to PP$ and $VP$ decays where $y$ can be reliably estimated. We conclude that $y_{{}_{PP}}\sim (0.110\pm 0.011)\%$ and the lower bound on $y_{{}_{VP}}$ is $(0.220\pm 0.071)\%$.

   hep-phhep-exPRD(2024)·34 citations
3. 03*

   NNLO QCD predictions of the asymmetry probe of the $Z\gamma$ pair-production process

   Kadir Saygin🇹🇷

   The paper presents for the first time a novel idea of exploiting asymmetry between differential cross sections of the $Z\gamma$ pair-production in proton-proton ($pp$) collisions for the final states of a charged-lepton pair plus a photon $pp\to Z\gamma \to l^{+}{l}^{-}\gamma$ (leptonic decay) and of a neutrino pair plus a photon $pp\to Z\gamma \to \nu \bar{\nu }\gamma$ (invisible decay). Asymmetry between the leptonic and invisible decays of the $Z\gamma$ process is investigated by using fixed-order predictions through inclusion of next-to-next-to-leading (NNLO) radiative corrections in quantum chromodynamics (QCD) perturbation theory. NNLO QCD predictions are presented at various $pp$-collision energies as functions of several key observables including transverse momenta and azimuthal-angle separation, regarding the $Z\gamma$ decay products. The predicted distributions for the $Z\gamma$ asymmetry are provided based on realistic fiducial phase-space requirements in line with the related hadron-collider measurements. The predicted distributions are assessed at various $pp$-collision energies and in different phase-space regions such as with higher lepton-pair invariant mass $m^{l^{+}{l}^{-}}$ or higher neutrino-pair transverse momentum $p_{\mathrm{T}}^{\nu \bar{\nu }}$ requirements. The $Z\gamma$ asymmetry is shown to be significantly sensitive in different regions of phase space including high-$m^{l^{+}{l}^{-}}$ and high-$p_{\mathrm{T}}^{\nu \bar{\nu }}$ regions. The $Z\gamma$ asymmetry can therefore be translated into an important quantity for probing deviation from the Standard Model (SM) predictions. In this regard, the asymmetry probe is proposed as a sensitive indicator for indirect searches for physics beyond the SM encompassing high-mass resonances and dark-matter sector.

   hep-phPhys.Scripta(2024)·0 citations
4. 04*

   Machine learning holographic black hole from lattice QCD equation of state

   Xun Chen🇨🇳 · Mei Huang🇨🇳

   Based on lattice QCD results of equation of state (EOS) and baryon number susceptibility at zero baryon chemical potential, and supplemented by machine learning techniques, we construct the analytic form of the holographic black hole metric in the Einstein-Maxwell-Dilaton (EMD) framework for pure gluon, 2-flavor, and 2+1-flavor systems, respectively. The dilaton potentials solved from Einstein equations are in good agreement with the extended non-conformal DeWolfe-Gubser-Rosen (DGR) type dilaton potentials fixed by lattice QCD EOS, which indicates the robustness of the EMD framework. The predicted critical endpoint (CEP) in the 2+1-flavor system is located at $(T^c$=0.094GeV, ${\mu }_B^c$=0.74GeV), which is close to the results from the realistic Polyakov-Nambu-Jona-Lasinio(PNJL) model, the functional renormalization group, and the holographic model with extended DeWolfe-Gubser-Rosen dilaton potential.

   hep-phhep-latPRD(2024)·63 citations
5. 05*

   Asymptotic behavior of the Fourier coefficients and the analytic structure of the QCD equation of state

   Miles Bryant🇺🇸 · Christian Schmidt🇩🇪 · Vladimir V. Skokov🇺🇸

   In this paper we study the universal properties of the baryon chemical potential Fourier coefficients in Quantum Chromodynamics. We show that by following a well-defined strategy, the Fourier coefficients can be used to locate Yang-Lee edge singularities associated with chiral phase transition (and by extension with the Roberge-Weiss) in the complex chemical potential plane. We comment on the viability of performing this analysis using lattice QCD data.

   hep-phPRD(2024)·5 citations
6. 06*

   Theory for the MUonE experiment

   A. Gurgone (on behalf of the MUonE collaboration)🇮🇹

   The MUonE experiment aims at providing a new independent evaluation of the leading hadronic contribution to the muon anomalous magnetic moment. The proposed method is based on the measurement of the running of the QED coupling in the space-like momentum region, through the elastic scattering of high-energy muons on atomic electrons. In this proceeding, the status of the theoretical effort for the MUonE experiment is reviewed. In order to achieve a competitive determination, the differential cross section of muon-electron scattering must be computed with an unprecedented precision of 10 ppm, which requires at least next-to-next-leading order corrections and the resummation of large logarithms. In addition, the simulation of the experiment needs an exhaustive theoretical description of the possible background processes, such as the lepton pair production in muon-nucleus scattering. All these processes must be implemented in a fully exclusive Monte Carlo event generator in order to be used in the MUonE data analysis.

   hep-phhep-exPoS(2024)·5 citations
7. 07*

   Spontaneous Hopf fibration in the two-Higgs-doublet model

   R. A. Battye🇬🇧 · S. J. Cotterill🇬🇧

   We show that energetic considerations enforce a Hopf fibration of the Standard Model topology within the 2HDM whose potential has either an $SO(3)$ or $U(1)$ Higgs-family symmetry. This can lead to monopole and vortex solutions. We find these solutions, characterise their basic properties and demonstrate the nature of the fibration along with the connection to Nambu's monopole solution. We point out that breaking of the $U(1{)}_{\mathrm{EM}}$ in the core of the defect can be a feature which leads to a non-zero photon mass there.

   hep-phastro-ph.COhep-thPRL(2024)·5 citations
8. 08*

   Balancing baryon and asymmetric dark matter excess

   V. A. Beylin🇷🇺 · M. Yu. Khlopov🇫🇷 · D. O. Sopin🇷🇺

   Effect of the electroweak non-conservation of the baryon number could be a key ingredient to explain the ratio of dark and baryonic densities. If dark matter is explained by dark atoms, in which stable -2n charged particles are bound with n nuclei of primordial helium, and this multiple charged particles possess SU(2) electroweak charges, the excess of -2n charged particles over their antiparticles can be related to baryon excess by sphaleron transitions. It provides relationship between the density of asymmetric dark atom dark matter and baryon asymmetry, The cosmological consequences of sphaleron transitions were considered for the minimal walking technicolor (WTC) model, which provides composite Higgs boson solution for the problem of Higgs boson mass divergence in the Standard model. The realisation of multi-component dark atom scenario is possible because the electric charges of new fermions are not fixed and several types of stable multiple charged states are possible. In particular cases the upper limits for the masses of techniparticles could be found, at which dark atom interpretation of dark matter is possible. These limits challenge search for multiple charged stable particles at the LHC.

   hep-phastro-ph.CO0 citations
9. 09*

   Compact objects in and beyond the Standard Model from non-perturbative vacuum scalarization

   Loris Del Grosso🇮🇹 · Paolo Pani🇮🇹 · Alfredo Urbano🇮🇹

   We consider a theory in which a real scalar field is Yukawa-coupled to a fermion and has a potential with two non-degenerate vacua. If the coupling is sufficiently strong, a collection of N fermions deforms the true vacuum state, creating energetically-favored false-vacuum pockets in which fermions are trapped. We embed this model within General Relativity and prove that it admits self-gravitating compact objects where the scalar field acquires a non-trivial profile due to non-perturbative effects. We discuss some applications of this general mechanism: i) neutron soliton stars in low-energy effective QCD, which naturally happen to have masses around 2 solar masses and radii around 10 km even without neutron interactions; ii) Higgs false-vacuum pockets in and beyond the Standard Model; iii) dark soliton stars in models with a dark sector. In the latter two examples, we find compelling solutions naturally describing centimeter-size compact objects with masses around 10^-6 solar masses, intriguingly in a range compatible with the OGLE+HSC microlensing anomaly. Besides these interesting examples, the mechanism of non-perturbative vacuum scalarization may play a role in various contexts in and beyond the Standard Model, providing a support mechanism for new compact objects that can form in the early universe, can collapse into primordial black holes through accretion past their maximum mass, and serve as dark matter candidates.

   hep-phastro-ph.COgr-qcPRD(2024)·15 citations
10. 10*

    Simple calculation of the Coulomb-nuclear corrections in $pp$ and $\bar{p}p$ scattering

    Loyal Durand🇺🇸 · Phuoc Ha🇺🇸

    We present a very simple method for calculating the mixed Coulomb-nuclear effects in the $pp$ and $\bar{p}p$ scattering amplitudes, and illustrate the method using simple models frequently used to describe their differential cross sections at small momentum transfers. Combined with the pure Coulomb and form-factor contributions to the scattering amplitude which are known analytically from prior work, and the unmixed nuclear or strong-interaction scattering amplitude, the results give a much simpler approach to fitting the measured $pp$ and $\bar{p}p$ cross sections and extracting information on the real part of the forward scattering amplitudes than methods now in use.

    hep-ph0 citations
11. 11*

    Dark fluxes from electromagnetic cascades

    Nikita Blinov🇨🇦 · Patrick J. Fox🇺🇸 · Kevin J. Kelly🇺🇸 · Pedro A.N. Machado🇺🇸 · Ryan Plestid🇺🇸

    We study dark sector production in electromagnetic (EM) cascades. This problem requires accurate simulations of Standard Model (SM) and dark sector processes, both of which impact angular and energy distributions of emitted particles that ultimately determine flux predictions in a downstream detector. We describe the minimal set of QED processes which must be included to faithfully reproduce a SM cascade, and identify a universal algorithm to generate a dark sector flux given a Monte-Carlo simulation of a SM shower. We provide a new tool, $\text{PETITE}$, which simulates EM cascades with associated dark vector production, and compare it against existing literature and "off the shelf" tools. The signal predictions at downstream detectors can strongly depend on the nontrivial interplay (and modelling) of SM and dark sector processes, in particular multiple Coulomb scattering and positron annihilation. We comment on potential impacts of these effects for realistic experimental setups.

    hep-phhep-exJHEP(2024)·21 citations
12. 12*

    Entanglement autodistillation from particle decays

    J. A. Aguilar-Saavedra🇪🇸 · J. A. Casas🇪🇸

    Particle decays do not constitute a spin ``measurement'' in the quantum-mechanical sense, but still modify the spin state, in particular for an entangled system. We show that for a spin-entangled pair of particles the entanglement of the system can increase after the decay of one particle. This unique phenomenon has no equivalent for stable particles and could be observable in top pair production at a high-energy polarized $e^{+}{e}^{-}$ collider.

    hep-phhep-exquant-phPRL(2024)·41 citations
13. 13*

    The Collinear Limit of the Four-Point Energy Correlator in $\mathcal{N}=4$ Super Yang-Mills Theory

    Dmitry Chicherin🇫🇷 · Ian Moult🇺🇸 · Emery Sokatchev🇫🇷 · Kai Yan🇨🇳 · Yunyue Zhu🇨🇳

    We present a compact formula, expressed in terms of classical polylogarithms up to weight three, for the leading order four-point energy correlator in maximally supersymmetric Yang-Mills theory, in the limit where the four detectors are collinear. This formula is derived by combining a simplified, manifestly dual conformal invariant form of the 1 -> 4 splitting function obtained from the square of the tree-level five-particle form factor of stress-tensor multiplet operators, with a novel integration-by-parts algorithm operating directly on Feynman parameter integrals. Our results provide valuable data for exploring the structure of physical observables in perturbation theory, and for calculations of jet substructure observables in quantum chromodynamics.

    ↳ hep-thhep-phPRD(2024)·43 citations
14. 14*

    Machine learning a fixed point action for SU(3) gauge theory with a gauge equivariant convolutional neural network

    Kieran Holland🇺🇸 · Andreas Ipp🇦🇹 · David I. Müller🇦🇹 · Urs Wenger🇨🇭

    Fixed point lattice actions are designed to have continuum classical properties unaffected by discretization effects and reduced lattice artifacts at the quantum level. They provide a possible way to extract continuum physics with coarser lattices, thereby allowing one to circumvent problems with critical slowing down and topological freezing toward the continuum limit. A crucial ingredient for practical applications is to find an accurate and compact parametrization of a fixed point action, since many of its properties are only implicitly defined. Here we use machine learning methods to revisit the question of how to parametrize fixed point actions. In particular, we obtain a fixed point action for four-dimensional SU(3) gauge theory using convolutional neural networks with exact gauge invariance. The large operator space allows us to find superior parametrizations compared to previous studies, a necessary first step for future Monte Carlo simulations and scaling studies.

    ↳ hep-latcs.LGhep-phstat.MLPRD(2024)·21 citations
15. 15*

    Dark matter search in dwarf irregular galaxies with ten years of data from the IceCube neutrino observatory

    Yi-Fei Lü🇨🇳 · Ben-Yang Zhu🇨🇳 · Rong-Lan Li🇨🇳 · Xue-Kang Guo🇨🇳 · Tian-Ci Liu🇨🇳 · Yong-Bo Huang🇨🇳 · Yun-Feng Liang🇨🇳

    Dwarf irregular galaxies (dIrrs), as rotationally-supported systems, have more reliable J-factor measurements than dwarf spheroidal galaxies and have received attention as targets for dark matter detection in recent years. In this paper, we use 10 years of IceCube muon-track data and an unbinned maximum-likelihood-ratio method to search for neutrino signals beyond the background from the directions of 7 dIrrs, aiming to detect neutrinos produced by heavy annihilation dark matter. We do not detect any significant signal. Based on such null results, we calculate the upper limits on the velocity-averaged annihilation cross section for 1 TeV - 10 PeV dark matter. Our limits, although weaker than the strictest constraints in the literature in this mass range, are also a good complement to the existing results considering the more reliable J-factor measurements of dIrrs.

    ↳ astro-ph.HEhep-phRes.Astron.Astrophys.(2024)·5 citations
16. 16*

    Physics perspectives of a CMS near-beam proton spectrometer at the HL-LHC

    Michael Pitt🇺🇸

    The High-Luminosity Large Hadron Collider (HL-LHC) is designed to achieve higher instantaneous luminosities, enabling the exploration of the rarest processes of the Standard Model (SM). The CMS collaboration has published an Expression of Interest to pursue the study of the central exclusive production processes, using near-beam detectors. This report details both the expected performance and the scientific potential of the CMS near-beam proton spectrometer at the HL-LHC.

    ↳ hep-exhep-phPoS(2024)·3 citations
17. 17*

    Incorporating $DD\pi$ effects and left-hand cuts in lattice QCD studies of the $T_{cc}(3875{)}^{+}$

    Maxwell T. Hansen🇬🇧 · Fernando Romero-López🇺🇸 · Stephen R. Sharpe🇺🇸

    We generalize the relativistic field-theoretic three-particle finite-volume scattering formalism to describe generic $DD\pi$ systems in the charm $C=2$ sector. This includes the isospin-0 channel, in which the recently discovered doubly-charmed tetraquark $T_{cc}(3875{)}^{+}$ is expected to manifest as a pole in the $DD\pi \to DD\pi$ scattering amplitude. The formalism presented here can also be applied to lattice QCD settings in which the $D^{\ast }$ is bound and, in particular, remains valid below the left-hand cut in $D{D}^{\ast }$ scattering, thus resolving an issue in previous analyses of lattice-determined finite-volume energies.

    ↳ hep-lathep-phnucl-thJHEP(2024)·76 citations
18. 18*

    Imaging Shapes of Atomic Nuclei in High-Energy Nuclear Collisions

    STAR Collaboration

    Atomic nuclei are self-organized, many-body quantum systems bound by strong nuclear forces within femtometer-scale space. These complex systems manifest a variety of shapes, traditionally explored using non-invasive spectroscopic techniques at low energies. However, at these energies, their instantaneous shapes are obscured by long-timescale quantum fluctuations, making direct observation challenging. Here we introduce the ``collective flow assisted nuclear shape imaging'' method, which images the nuclear global shape by colliding them at ultrarelativistic speeds and analyzing the collective response of outgoing debris. This technique captures a collision-specific snapshot of the spatial matter distribution within the nuclei, which, through the hydrodynamic expansion, imprints patterns on the particle momentum distribution observed in detectors. We benchmark this method in collisions of ground state Uranium-238 nuclei, known for their elongated, axial-symmetric shape. Our findings show a large deformation with a slight deviation from axial symmetry in the nuclear ground state, aligning broadly with previous low-energy experiments. This approach offers a new method for imaging nuclear shapes, enhances our understanding of the initial conditions in high-energy collisions and addresses the important issue of nuclear structure evolution across energy scales.

    ↳ nucl-exhep-exhep-phnucl-thNature(2024)·148 citations
19. 19*

    An analytic approach to the RTA Boltzmann attractor

    Inês Aniceto🇬🇧 · Jorge Noronha🇺🇸 · Michał\ Spaliński🇵🇱

    We reformulate the Boltzmann equation in the relaxation time approximation undergoing Bjorken flow in terms of a novel partial differential equation for the generating function of the moments of the distribution function. This is used to obtain an approximate analytic description of this system's far-from-equilibrium attractor via a series expansion at early times. This expansion possesses a finite radius of convergence and can be analytically continued to late times. We find that this procedure reproduces the known values of shear viscosity and other transport coefficients to high accuracy. We also provide a simple approximate analytic expression that describes the attractor in the entire domain of interest for studies of quark-gluon plasma dynamics.

    ↳ nucl-thhep-phhep-thPRD(2025)·11 citations
20. 20*

    An alternative to perturbative renormalization in 3+1 dimensional field theories

    Paul Romatschke🇺🇸

    Perturbative renormalization provides the bedrock of understanding quantum field theories. In this work, I point out an alternative way of renormalizing quantum field theories, which is naturally encountered and well known for the case of large N scalar field theories. In terms of bare parameters, this non-perturbative alternative renormalization differs qualitatively from its perturbative cousin: in the continuum limit, the bare coupling constant goes to zero instead of infinity, and there is no wave-function counterterm. Despite these differences, the resulting n-point functions of the theory are finite. I provide explicit results for alternative renormalization for the O(N) model and QCD with $N_f=12$ flavors in 3+1 dimensions.

    ↳ hep-thhep-phnucl-thPRD(2024)·8 citations
21. 21*

    Minimal Black Holes and Species Thermodynamics

    Ivano Basile🇩🇪 · Niccolò Cribiori🇩🇪 · Dieter Lust🇩🇪 · Carmine Montella🇩🇪

    The species scale provides a lower bound on the shortest possible length that can be probed in gravitational effective theories. It may be defined by the size of the minimal black hole in the theory and, as such, it has recently been given an interpretation along the lines of the celebrated black hole thermodynamics. In this work, we extend this interpretation to the case of charged species. We provide working definitions of minimal black holes for the case of uncharged and charged species constituents. Then, examining the modifications in the thermodynamic properties of near-extremal charged species compared to the uncharged case, we uncover interesting implications for the cosmology of an expanding universe, particularly within the context of the Dark Dimensions Scenario. Finally, we explore possible microscopic constructions in non-supersymmetric string theories in which towers of charged near-extremal species may arise.

    ↳ hep-thhep-phJHEP(2024)·54 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.