Fri·Apr 5, 2024Friday·April 5, 2024

1. 01*

   Glue in hadrons at medium resolution and the QCD instanton vacuum

   Wei-Yang Liu🇺🇸 · Edward Shuryak🇺🇸 · Ismail Zahed🇺🇸

   We discuss a general framework for the evaluation of the gluonic form factors in light hadrons at low momentum transfer, in the QCD instanton vacuum. At medium resolution of the order of the inverse mean instanton size, the glue is mostly localized in single or pair of pseudoparticles, and globally constrained by the fluctuations of their topological charges. These pseudoparticles trap light quarks, giving rise to emerging multiflavor 't Hooft interactions. We explicitly evaluate the gluonic scalar, pseudoscalar, energy-momentum tensor (EMT), and the leading C-odd and C-even three gluons hadronic form factors, at next to leading order (NLO) in the instanton density, including molecular clusters of like and unlike instantons. We use the results for the EMT to address the contribution of the gluons in Ji${}^{\prime }$s mass and spin sum rules, at low resolution. When evolved, our results for the mass and spin composition of the nucleon, are shown to be in good agreement with the recently reported lattice results at higher resolution.

   hep-phhep-thnucl-thPRD(2024)·23 citations
2. 02*

   Direct detection of light dark matter charged under a $L_{\mu }-L_{\tau }$ symmetry

   Pablo Figueroa🇩🇪 · Gonzalo Herrera🇺🇸 · Fredy Ochoa🇨🇴

   A possible extension of the Standard Model able to explain the recent measurement of the anomalous magnetic moment of the muon consists in adding a gauged $U(1{)}_{L_{\mu }-L_{\tau }}$ symmetry. If the dark matter particle is charged under this symmetry, the kinetic mixing between the new gauge boson and the photon induces dark matter-electron interactions. We derive direct detection constraints on light dark matter charged under a $U(1{)}_{L_{\mu }-L_{\tau }}$ symmetry with electron recoil experiments, and explore prospects with XLZD and OSCURA to close in the parameter space able to explain simultaneously the recent measurement on the anomalous magnetic moment of the muon and the observed relic density of dark matter. We further discuss the spin-dependent scattering contribution arising in this model, which was ignored previously in the literature.

   hep-phastro-ph.COPRD(2024)·17 citations
3. 03*

   Discrete origins of matter

   Gauhar Abbas · Neelam Singh

   We discuss models of the flavour problem and dark matter based on the discrete ${\mathcal{Z}}_{\mathrm{N}}\times {\mathcal{Z}}_{\mathrm{M}}\times {\mathcal{Z}}_{\mathrm{P}}$ flavour symmetry. A new class of dark-matter emerges out of these models, which is defined as the flavonic dark matter. An ultra-violet completion of these models based on the dark-technicolour paradigm is also presented.

   hep-phhep-ex5 citations
4. 04*

   On bipartite and tripartite entanglement at present and future particle colliders

   Amir Subba🇮🇳 · Rafiqul Rahaman🇮🇳

   Entanglement, rooted in the non-deterministic, non-local nature of quantum mechanics, serves as a fundamental correlation. High-energy particle colliders offer a unique platform for exploring entanglement in the relativistic regime. The recent observation of entanglement in $t\bar{t}$ production by ATLAS has sparked significant interest in investigating entanglement phenomena at colliders. While bipartite entanglement receives extensive attention, tripartite entanglement remains relatively uncharted. We investigate tripartite entanglement in $t\bar{t}Z$ production at the Large Hadron Collider (LHC) within the Standard Model and with a dimension-$8$ effective operator. Additionally, we explore bipartite entanglement in $t\bar{t}$, $t{W}^{-}$, and di-boson production processes, namely $W^{+}{W}^{-}$, $ZZ$, and $W^{+}Z$, at the LHC and future $e^{+}{e}^{-}$ collider. We numerically compute various measures of entanglement through Monte Carlo events based on the spin density matrix, with its elements (polarization and spin correlation) obtained by analyzing the angular distribution of the final decayed leptons.

   hep-phhep-th35 citations
5. 05*

   ToMCCA: A Toy Monte Carlo Coalescence Afterburner

   Maximilian Mahlein🇩🇪 · Chiara Pinto🇩🇪 · Laura Fabbietti🇩🇪

   The study of antinuclei in cosmic rays provides a unique opportunity to probe physics beyond the Standard Model. Antinuclei in our Galaxy may stem either from annihilation or decay of dark matter, or from collisions of cosmic rays with the interstellar medium, which constitute the background of indirect dark matter searches. Understanding the formation mechanism of (anti)nuclei is crucial for setting limits on their production in space. Coalescence models, which describe the formation of light nuclei from final-state interaction of nucleons, have been widely employed in high-energy collisions. In this work, we introduce ToMCCA (Toy Monte Carlo Coalescence Afterburner), which allows for detailed studies of the nuclear formation processes without the overload of general-purpose event generators. ToMCCA contains parameterizations of the multiplicity dependence of the transverse momentum distributions of protons and of the baryon-emitting source size, extracted from ALICE measurements in pp collisions at $\sqrt{s}=5-13$ TeV, as well as of the event multiplicity distributions, taken from the EPOS event generator. ToMCCA provides predictions of the deuteron transverse momentum distributions, with an agreement of $\sim 5\%$ with the experimental data. The results of ToMCCA show that the coalescence mechanism in pp collisions depends only on the event multiplicity rather than on the collision system or its energy. This allows the model to be utilized for predictions at lower center-of-mass collision energies, which are the most relevant for the production of antinuclei from processes related to dark matter. This model can also be extended to heavier nuclei as long as the target nucleus wave function and its Wigner function are known.

   hep-phhep-exEPJC(2024)·11 citations
6. 06*

   Fractional-charge hadrons and leptons to tell the Standard Model group apart

   Rodrigo Alonso🇬🇧 · Despoina Dimakou🇬🇧 · Mia West🇬🇧

   The gauge group of strong and electroweak interactions in Nature could be any of the four that share the same Lie algebra, $SU(3{)}_c\times SU(2{)}_L\times U(1{)}_Y/Z_p\equiv G_p$ with $Z_p=\left\{Z_6,Z_3,Z_2,Z_1\right\}$. Each of these cases allows in its spectrum for the matter fields of the SM but also for new distinctive representations, e.g. under the assumption that $q_L$ possesses the minimum possible hypercharge in Nature, $G_p$ allows for particles with a multiple of $pe/6$ for electric charge. This letter discusses how these new possibilities in the spectrum could be used to tell the SM group apart.

   hep-phPLB(2025)·28 citations
7. 07*

   Inclusive $\bar{B}\to X_s{\ell }^{+}{\ell }^{-}$ at the LHC: theory predictions and new-physics reach

   Tobias Huber🇩🇪 · Tobias Hurth🇩🇪 · Jack Jenkins🇩🇪 · Enrico Lunghi🇺🇸 · Qin Qin🇨🇳 · K. Keri Vos🇳🇱

   We present theoretical predictions for observables in inclusive $\bar{B}\to X_s{\ell }^{+}{\ell }^{-}$ suitable for measurements at hadron colliders through a sum-over-exclusive approach. At low $q^2$ we calculate the branching ratio and three angular observables. At high $q^2$ we provide the branching ratio and the ratio of the $\bar{B}\to X_s{\ell }^{+}{\ell }^{-}$ rate with respect to the inclusive $\bar{B}\to X_u\ell \bar{\nu }$ rate with the same phase-space cut. We compare our predictions to the $B$ factory measurements and also to an extraction of the experimental rate through a sum-over-exclusive method using branching ratios of the exclusive $\bar{B}\to K^{(\ast )}{\mu }^{+}{\mu }^{-}$ modes measured at LHCb. We find a consistent picture comparing Standard Model theory and experiment. As such, our analysis does not support a recent claim about a deficit in the inclusive branching ratio in the high-$q^2$ region. Finally, we present current model-independent bounds on new physics and emphasize the potential of complementary analyses of $\bar{B}\to X_s{\ell }^{+}{\ell }^{-}$ at Belle II and the LHC.

   hep-phhep-exJHEP(2024)·14 citations
8. 08*

   Deformation-induced CPT violation in entangled pairs of neutral kaons

   Andrea Bevilacqua🇵🇱 · Jerzy Kowalski-Glikman🇵🇱 · Wojciech Wislicki🇵🇱

   In this paper we consider description of kaon -- anti-kaon interference in the context of a theory with deformed $\mathcal{C}\mathcal{P}\mathcal{T}$ symmetry. In the case of such theoretical models, deviations from the standard $\mathcal{C}\mathcal{P}\mathcal{T}$ invariance is related to the momentum carried by the particles; in particular the rest masses of particles and antiparticles are equal. We find that the decay intensity of kaon -- anti-kaon pair has three contributing terms: the correct-parity, the wrong-parity, and the interference between them, all of which are affected by deformation. Using the fact that the presence of such terms were not observed we estimate the magnitude of deformation parameter $\kappa \gtrsim 10^{18}$ GeV, very close to the expected Planck mass scale. This raises hopes that the effect, if exists, could be detected in a near future accelerator experiments. An uncertainty of the energy measurement is crucial for accuracy of these predictions.

   hep-phgr-qchep-thPRD(2024)·7 citations
9. 09*

   Exploring scalar contributions with $K^{+}\to {\pi }^{+}{\ell }^{+}{\ell }^{-}$

   G. D'Ambrosio🇮🇹 · A.M. Iyer🇮🇳 · F. Mahmoudi🇫🇷 · S. Neshatpour🇫🇷

   The rare kaon decay $K^{+}\to {\pi }^{+}{\ell }^{+}{\ell }^{-}$ offers insights into Standard Model (SM) physics and beyond. Driven by vector form factor in the SM, it can also probe non-standard contributions. In this letter we study the scalar contribution, $f_S$. Using differential decay width and Forward-Backward Asymmetry we propose a simultaneous fit to vector and scalar contributions which is necessary for a consistent analysis. Novel bounds on $|f_S|$ are presented for the first time through a reinterpretation of the E865, NA48/2, and NA62 experimental results. The analysis results in the most precise bound $f_S<7.9\times 10^{-6}$ at 90$\%$ confidence level.

   hep-phhep-exPLB(2024)·6 citations
10. 10*

    A new 700 GeV scalar in the LHC data?

    Maurizio Consoli🇮🇹 · George Rupp🇵🇹

    As an alternative to the metastability of the electroweak vacuum, resulting from perturbative calculations, one can consider a non-perturbative effective potential which, as at the beginning of the Standard Model, is restricted to the pure ${\Phi }^4$ sector yet consistent with the known analytical and numerical studies. In this approach, where the electroweak vacuum is now the lowest-energy state, besides the resonance of mass $m_h=$ 125 GeV defined by the quadratic shape of the potential at its minimum, the Higgs field should exhibit a second resonance with mass $(M_H{)}^{\mathrm{Theor}}=690(30)$ GeV associated with the zero-point energy determining the potential depth. In spite of its large mass, this resonance would couple to longitudinal $W$s with the same typical strength as the low-mass state at 125 GeV and represent a relatively narrow resonance, mainly produced at LHC by gluon-gluon fusion. In this Letter, we review LHC data suggesting a new resonance of mass $(M_H{)}^{\mathrm{EXP}}\sim 682(10)$ GeV, with a statistical significance that is far from negligible.

    hep-phhep-exLHEP(2024)·3 citations
11. 11*

    Dimension-eight Operator Basis for Universal Standard Model Effective Field Theory

    Tyler Corbett🇦🇹 · Jay Desai🇺🇸 · O. J. P. Eboli🇧🇷 · M. C. Gonzalez-Garcia🇺🇸

    We present the basis of dimension-eight operators associated with universal theories. We first derive a complete list of independent dimension-eight operators formed with the Standard Model bosonic fields characteristic of such universal new physics scenarios. Without imposing C or P symmetries the basis contains 175 operators -- that is, the assumption of Universality reduces the number of independent SMEFT coefficients at dimension eight from 44807 to 175. 89 of the 175 universal operators are included in the general dimension-eight operator basis in the literature. The 86 additional operators involve higher derivatives of the Standard Model bosonic fields and can be rotated in favor of operators involving fermions using the Standard Model equations of motion for the bosonic fields. By doing so we obtain the allowed fermionic operators generated in this class of models which we map into the corresponding 86 independent combinations of operators in the dimension-eight basis of Ref. arXiv:2005.00059

    hep-phPRD(2024)·17 citations
12. 12*

    Falsifying Anthropics

    Nemanja Kaloper🇺🇸 · Alexander Westphal🇩🇪

    We propose using fuzzy axion dark matter to test the anthropic principle. A very light axion can be directly detectable, at least by black hole superradiance effects. The idea then is that gravitational and astrophysical observations can discover a light axion in the regime where it must be all of dark matter with abundance which must be set up by the anthropic principle, due to excessive primordial misalignment induced by inflation-induced Brownian drift of fluctuations. Yet it may turn out that dark matter is something else instead of this axion. Since the de Sitter-induced axion misalignment controlled only by the de Sitter curvature cannot be evaded, this would invalidate the anthropic prediction of the dark matter abundance.

    ↳ hep-thastro-ph.COgr-qchep-phJCAP(2024)·2 citations
13. 13*

    Neutrino mean free path in neutron stars in the presence of hyperons

    Jesper Leong🇦🇺 · Parada T. P. Hutauruk🇰🇷 · Anthony W. Thomas🇦🇺

    We investigate the neutrino elastic differential cross-section (NDCS) and corresponding mean free path for neutral current scattering in the dense matter of a neutron star. A wide range of observed neutron star (NS) masses is considered, including the presence of $\Lambda$, ${\Xi }^{-}$, and ${\Xi }^0$ hyperons in the heaviest stars. Their presence significantly decreases the total neutrino mean free path in the heavier stars.

    ↳ nucl-thastro-ph.HEastro-ph.SRhep-phPRC(2024)·0 citations
14. 14*

    Primordial Black Hole Interpretation in Subsolar Mass Gravitational Wave Candidate SSM200308

    Chen Yuan🇵🇹 · Qing-Guo Huang🇨🇳

    In the recent second part of the third observation run by the LIGO-Virgo-KAGRA collaboration, a candidate with sub-solar mass components was reported, which we labelled as SSM200308. This study investigates the premise that primordial black holes (PBHs), arising from Gaussian perturbation collapses, could explain SSM200308. Through Bayesian analysis, we obtain the primordial curvature power spectrum that leads to the merger rate of PBHs aligning with observational data as long as they constitute {$f_{\mathrm{PBH}}=5.66_{-5.44}^{+58.68}\times 10^{-2}$ } of the dark matter. However, while the gravitational wave (GW) background from binary PBH mergers is within current observational limits, the scalar-induced GWs associated with PBH formation exceed the constraints imposed by pulsar timing arrays, challenging the Gaussian perturbation collapse PBH model as the source of SSM200308.

    ↳ astro-ph.COgr-qchep-phJCAP(2024)·16 citations
15. 15*

    Wilson Loops and Random Matrices

    Georg Bergner🇩🇪 · Vaibhav Gautam🇬🇧 · Masanori Hanada🇬🇧 · Jack Holden🇬🇧

    Linear confinement with Casimir scaling of the string tension in confining gauge theories is a consequence of a certain property of the Polyakov loop related to random matrices. This mechanism does not depend on the details of the theories (neither the gauge group nor dimensions) and explains approximate Casimir scaling below string-breaking length. In this paper, we study 3d SU(2) pure Yang-Mills theory numerically and find the same random-matrix behavior for rectangular Wilson loops. We conjecture that this is a universal feature of strongly coupled confining gauge theories.

    ↳ hep-thhep-lathep-phJHEP(2024)·3 citations
16. 16*

    Quantum querying based on multicontrolled Toffoli gates for causal Feynman loop configurations and directed acyclic graphs

    Selomit Ramírez-Uribe🇪🇸 · Andrés E. Rentería-Olivo🇪🇸 · Germán Rodrigo🇪🇸

    Quantum algorithms are a promising framework for unfolding the causal configurations of multiloop Feynman diagrams, which is equivalent to querying the \textit{directed acyclic graph} (DAG) configurations of undirected graphs in graph theory. In this paper, we present a quantum algorithm for querying in both types of applications, using a systematic and sparing logic in the design of an oracle operator. The construction of the quantum oracle is based exclusively on multicontrolled Toffoli (MCX) gates and quantum NOT (Pauli-$X$) gates. The efficiency of the algorithm is evaluated by comparison with a quantum algorithm based on binary clauses. Furthermore, we analyse the impact of traspilation and introduce an appropriate metric to assess the complexity of the algorithm, the \emph{quantum circuit area}. We explicitly analyse three-, four- and five-eloop topologies, which have not previously been explored due to their higher complexity and the current limitations of quantum simulators.

    ↳ quant-phhep-phhep-th20 citations
17. 17*

    Constraints on the Dirac spectrum from chiral symmetry restoration

    Matteo Giordano🇭🇺

    I derive constraints on the Dirac spectrum in the chirally symmetric phase of a gauge theory with two massless fermion flavors. Using only general properties of correlation functions of scalar and pseudoscalar bilinears, I prove that in the chiral limit of vanishing fermion mass $m$ the corresponding susceptibilities and all their derivatives with respect to $m^2$ must be finite. I then use the resulting spectral constraints to show that effective breaking of the anomalous $\mathrm{U}(1{)}_A$ symmetry is allowed in the $\mathrm{SU}(2{)}_A$ symmetric phase in the chiral limit, and leads to distinctive spectral features: (i) the spectral density must develop a singular $O(m^4)/\lambda$ peak as $m\to 0$, (ii) the two-point eigenvalue correlator of near-zero modes must be singular, and (iii) near-zero modes cannot be localized. Moreover, in the symmetric phase the topological charge distribution must be indistinguishable from that of an ideal gas of instantons and anti-instantons of vanishing density, to leading order in $m$.

    ↳ hep-latcond-mat.dis-nnhep-phhep-thPRD(2024)·16 citations
18. 18*

    $\bar{b}\bar{b}ud$ and $\bar{b}\bar{b}us$ tetraquarks from lattice QCD using symmetric correlation matrices with both local and scattering interpolating operators

    Constantia Alexandrou🇨🇾 · Jacob Finkenrath🇩🇪 · Theodoros Leontiou🇨🇾 · Stefan Meinel🇺🇸 · Martin Pflaumer🇩🇪 · Marc Wagner🇩🇪

    We study the $\bar{b}\bar{b}ud$ tetraquark with quantum numbers $I(J^P)=0(1^{+})$ as well as the $\bar{b}\bar{b}us$ tetraquark with quantum numbers $J^P=1^{+}$ using lattice QCD. We improve on existing work by including both local and scattering interpolating operators on both sides of the correlation functions and use symmetric correlation matrices. This allows not only a reliable determination of the energies of QCD-stable tetraquark ground states, but also of low-lying excited states, which are meson-meson scattering states. The latter is particularly important for future finite-volume scattering analyses. Here, we perform chiral and continuum extrapolations of just the ground-state energies, for which finite-volume effects are expected to be small. Our resulting tetraquark binding energies, $-100\pm 10{}_{-51}^{+36}\mathrm{MeV}$ for $\bar{b}\bar{b}ud$ and $-30\pm 3{}_{-31}^{+11}\mathrm{MeV}$ for $\bar{b}\bar{b}us$, are consistent with other recent lattice-QCD predictions.

    ↳ hep-lathep-phPRD(2024)·40 citations
19. 19*

    Particle production and entropy measurement in ALICE

    Alek Hutson (On behalf of the ALICE collaboration)🇺🇸

    One of the main goals in the study of hadronic interactions at LHC energies is the attempt to characterize the mechanisms involved in particle production in different regimes. The charged-particle multiplicity is one of the most interesting observables in these kind of studies. Measurements of charged-particle pseudorapidity densities in pp collisions at $\sqrt{\text{s}}$ = 13.6 TeV are presented, for the first time. Furthermore, we present a method for better understanding the collision dynamics. On the one hand, the pseudorapidity dependence of charged-particle production provides information on the partonic structure of the colliding hadrons and is sensitive to non-linear QCD evolution in the initial state. On the other hand to understand the thermal-like behavior and particle yields in pp collisions, a possible approach is to address the principles of quantum states and their entanglement in the produced system. The entanglement in the initial state has a measurable effect on the evolution of the system and is the driving mechanism behind the thermal-like behavior and particle yields observed. We describe a method to understand the level of entanglement in the initial and final states of the collision using a calculation of entropy, the final-state entropy being calculated from multiplicity distributions.

    ↳ hep-exhep-phEPJ Web Conf.(2024)·0 citations
20. 20*

    Structure and Complexity of Cosmological Correlators

    Thomas W. Grimm🇳🇱 · Arno Hoefnagels🇳🇱 · Mick van Vliet🇳🇱

    Cosmological correlators capture the spatial fluctuations imprinted during the earliest episodes of the universe. While they are generally very non-trivial functions of the kinematic variables, they are known to arise as solutions to special sets of differential equations. In this work we use this fact to uncover the underlying tame structure for such correlators and argue that they admit a well-defined notion of complexity. In particular, building upon the recently proposed kinematic flow algorithm, we show that tree-level cosmological correlators of a generic scalar field theory in an FLRW spacetime belong to the class of Pfaffian functions. Since Pfaffian functions admit a notion of complexity, we can give explicit bounds on the topological and computational complexity of cosmological correlators. We conclude with some speculative comments on the general tame structures capturing all cosmological correlators and the connection between complexity and the emergence of time.

    ↳ hep-thhep-phPRD(2024)·25 citations
21. 21*

    Quantity and quantitative properties in physics and metrology

    Savely G. Karshenboim🇩🇪

    I discuss various aspects of the concept of a quantity in physics and metrology and related consideration in reference documents of IUPAP, IUPAC, ISO, IEC, and JCGM.

    ↳ physics.class-phhep-ph0 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.