Thu·Mar 16, 2023Thursday·March 16, 2023

1. 01*

   Impact of high invariant-mass Drell-Yan forward-backward asymmetry measurements on SMEFT fits

   Radja Boughezal🇺🇸 · Yingsheng Huang🇺🇸 · Frank Petriello🇺🇸

   We study the impact of LHC forward-backward asymmetry (AFB) measurements at high invariant-mass in the Drell-Yan process on probes of semileptonic four-fermion operators in the Standard Model effective field theory (SMEFT). In particular, we study whether AFB measurements can resolve degeneracies in the Wilson coefficient parameter space that appear when considering invariant-mass and rapidity measurements alone. We perform detailed fits of the available high-energy and high-luminosity ATLAS and CMS data for both invariant-mass distributions and AFB. While each type of measurement separately exhibits degeneracies, combining them removes these blind spots in some cases. In other situations it does not, highlighting the importance of incorporating future datasets from other experiments to fully explore this sector of the SMEFT. We investigate the impact of contributions quadratic in the Wilson coefficients on the description of Drell-Yan data and discuss when such terms are important in joint fits of the AFB and invariant-mass data.

   hep-phPRD(2023)·21 citations
2. 02*

   Colloquium: Gravitational Form Factors of the Proton

   V. D. Burkert🇺🇸 · L. Elouadrhiri🇺🇸 · F. X. Girod🇺🇸 · C. Lorce🇫🇷 · P. Schweitzer🇺🇸 · P. E. Shanahan🇺🇸

   The physics of the gravitational form factors of the proton, and their understanding within quantum chromodynamics, has advanced significantly in the past two decades through both theory and experiment. This Colloquium provides an overview of this progress, highlights the physical insights unveiled by studies of gravitational form factors, and reviews their interpretation in terms of the mechanical properties of the proton.

   hep-phhep-exhep-latnucl-thRMP(2023)·150 citations
3. 03*

   Global fits of simplified models for dark matter with GAMBIT II. Vector dark matter with an $s$-channel vector mediator

   Christopher Chang🇦🇺 · Pat Scott🇦🇺 · Tomás E. Gonzalo🇩🇪 · Felix Kahlhoefer🇩🇪 · Martin White🇦🇺

   Global fits explore different parameter regions of a given model and apply constraints obtained at many energy scales. This makes it challenging to perform global fits of simplified models, which may not be valid at high energies. In this study, we derive a unitarity bound for a simplified vector dark matter model with an $s$-channel vector mediator, and apply it to global fits of this model with \GB in order to correctly interpret missing energy searches at the LHC. Two parameter space regions emerge as consistent with all experimental constraints, corresponding to different annihilation modes of the dark matter. We show that although these models are subject to strong validity constraints, they are currently most strongly constrained by measurements less sensitive to the high-energy behaviour of the theory. Understanding when these models cannot be consistently studied will become increasingly relevant as they are applied to LHC Run 3 data.

   hep-phEPJC(2023)·16 citations
4. 04*

   The effect of non-equal emission times and space-time correlations on (anti-) nuclei production

   M.Kachelriess🇳🇴 · S.Ostapchenko🇩🇪 · J.Tjemsland🇳🇴

   Light (anti-) nuclei are a powerful tool both in collider physics and astrophysics. In searches for new and exotic physics, the expected small astrophysical backgrounds at low energies make these antinuclei ideal probes for, e.g., dark matter. At the same time, their composite structure and small binding energies imply that they can be used in collider experiments to probe the hadronisation process and two-particle correlations. For the proper interpretation of such experimental studies, an improved theoretical understanding of (anti-) nuclei production in specific kinematic regions and detector setups is needed. In this work, we develop a coalescence framework for (anti-) deuteron production which accounts for both the emission volume and momentum correlations on an event-by-event basis. This framework goes beyond the equal-time approximation, which has been commonly assumed in femtoscopy experiments and (anti-) nucleus production models until now. Using PYTHIA~8 as an event generator, we find that the equal-time approximation leads to an error of O(10%) in low-energy processes like ${\rm Y}$ decays, while the errors are negligible at LHC energies. The framework introduced in this work paves the way for tuning event generators to (anti-) nuclei measurements.

   hep-phnucl-thPRC(2023)·11 citations
5. 05*

   Contributions of $K_0^{\ast }(1430)$ and $K_0^{\ast }(1950)$ in the charmed three-body $B$ meson decays

   Bo-Yan Cui🇨🇳 · Ya-Hui Chen🇨🇳

   In this work, we investigate the resonant contributions of $K_0^{\ast }(1430)$ and $K_0^{\ast }(1950)$ in the three-body $B_{(s)}\to D_{(s)}K\pi$ within the perturbative QCD approach. The form factor $F_{k\pi }(s)$ are adopted to describe the nonperturbative dynamics of the S-wave $K\pi$ system. The branching ratios of all concerned decays are calculated and predicted to be in the order of $10^{-10}$ to $10^{-5}$. The ratio $R$ of branching fractions between $B^0\to {\bar{D}}^0{K}_0^{\ast 0}(1430)\to {\bar{D}}^0{K}^{+}{\pi }^{-}$ and $B_s^0\to {\bar{D}}^0{\bar{K}}_0^{\ast 0}(1430)\to {\bar{D}}^0{K}^{-}{\pi }^{+}$ are predicted to be 0.0552, which implies the discrepancy for the LHCb measurements. We expect that the predictions in this work can be tested by the future experiments, especially, to resolve $R$ ratio discrepancy.

   hep-phAdv.High Energy Phys.(2023)·0 citations
6. 06*

   Probing universal dynamics with topological data analysis in a gluonic plasma

   Daniel Spitz🇩🇪 · Kirill Boguslavski🇦🇹 · Jürgen Berges🇩🇪

   We study nonequilibrium dynamics of SU(2) lattice gauge theory in Minkowski space-time in a classical-statistical regime, where characteristic gluon occupancies are much larger than unity. In this strongly correlated system far from equilibrium, the correlations of energy and topological densities show self-similar behavior related to a turbulent cascade towards higher momentum scales. We employ persistent homology to infer topological features of the gluonic plasma via a hierarchy of simplicial and cubical complexes. All topological observables under investigation are also manifestly gauge invariant and are shown to exhibit self-similar evolution, which relate the spatial and temporal properties of the plasma in terms of universal scaling exponents and functions. The findings may help to understand the early stages of heavy-ion collisions in the limit of high energies, and our methods can also facilitate the topological analysis of other complex systems such as encountered in experiments with ultracold quantum gases.

   hep-phhep-latnucl-thPRD(2023)·11 citations
7. 07*

   Low projectile density contributions in the dilute-dense CGC framework for two-particle correlations

   Anderson Kendi Kohara🇵🇱 · Cyrille Marquet🇫🇷 · Víctor Vila🇵🇹

   At leading-order, the standard dilute-dense Color Glass Condensate formula used for two-particle correlations in proton-nucleus collisions, whose symmetries prevent the generation of odd azimuthal anisotropy harmonics, is the dilute projectile limit of the dense-dense formalism. However, when the projectile is genuinely dilute, the complete formulation contains additional contributions at the same leading order in the strong coupling constant. In this work we investigate those low projectile density contributions that are relevant when the particles are produced at forward rapidities. We find that they are responsible for non-zero odd harmonics which are negative, in qualitative agreement with recent experimental measurements at the Relativistic Heavy-Ion Collider.

   hep-phJHEP(2023)·3 citations
8. 08*

   New Perspectives for Testing Electron-Muon Universality

   Robert Fleischer🇳🇱 · Eleftheria Malami🇳🇱 · Anders Rehult🇳🇱 · K. Keri Vos🇳🇱

   Intriguing results for tests of the universality of electrons and muons through measurements of rates of $B\to K{\ell }^{+}{\ell }^{-}$ and similar decays have been in the spotlight for years. The LHCb collaboration has recently reported new results which are in agreement with Lepton Flavour Universality, while the individual decay rates are found below their Standard Model predictions. In view of this new situation, we explore how much space is left for a violation of electron-muon universality. Considering new sources of CP violation and taking the new LHCb measurements into account, we show that significant differences between the short-distance coefficients for electronic and muonic final states are actually allowed by the current data. These patterns can be revealed through CP asymmetries in neutral and charged $B\to K{\ell }^{+}{\ell }^{-}$ decays. We obtain correlations between these observables and map them to the short-distance coefficients. This results in regions in New Physics parameter space with large differences between CP asymmetries of the decays with final-state electrons and muons, thereby leaving a lot of room for possible surprises in the future high-precision era.

   hep-phhep-exJHEP(2023)·22 citations
9. 09*

   Evaluating master integrals in non-factorizable corrections to $t$-channel single-top production at NNLO QCD

   Zihao Wu🇨🇳 · Ming-Ming Long🇩🇪

   We studied the two-loop non-factorizable Feynman diagrams for the $t$-channel single-top production process in quantum chromodynamics. We present a systematic computation of master integrals of the two-loop Feynman diagrams with one internal massive propagator in which a complete uniform transcendental basis can be built. The master integrals are derived by means of canonical differential equations and uniform transcendental integrals. The results are expressed in the form of Goncharov polylogarithm functions, whose variables are the scalar products of external momenta, as well as the masses of the top quark and the $W$ boson. We also gave a discussion on the diagrams with potential elliptic sectors.

   hep-phhep-thJHEP(2023)·2 citations
10. 10*

    A Consistent View of Interacting Dark Energy from Multiple CMB Probes

    Yuejia Zhai🇬🇧 · William Giarè🇬🇧 · Carsten van de Bruck🇬🇧 · Eleonora Di Valentino🇬🇧 · Olga Mena🇪🇸 · Rafael C. Nunes🇧🇷

    We analyze a cosmological model featuring an interaction between dark energy and dark matter in light of the measurements of the Cosmic Microwave Background released by three independent experiments: the most recent data by the Planck satellite and the Atacama Cosmology Telescope, and WMAP (9-year data). We show that different combinations of the datasets provide similar results, always favoring an interacting dark sector with a $95\%$~CL significance in the majority of the cases. Remarkably, such a preference remains consistent when cross-checked through independent probes, while always yielding a value of the expansion rate $H_0$ consistent with the local distance ladder measurements. We investigate the source of this preference by scrutinizing the angular power spectra of temperature and polarization anisotropies as measured by different experiments.

    ↳ astro-ph.COgr-qchep-phJCAP(2023)·89 citations
11. 11*

    Motivation for Two Detectors at a Particle Physics Collider

    Paul D. Grannis🇺🇸 · Hugh E. Montgomery🇺🇸

    It is generally accepted that it is preferable to build two general purpose detectors at any given collider facility. We reinforce this point by discussing a number of aspects and particular instances in which this has been important. The examples are taken mainly, but not exclusively, from experience at the Tevatron collider.

    ↳ hep-exhep-phnucl-ex3 citations
12. 12*

    Greybody factors for higher-dimensional non-commutative geometry inspired black holes

    Zachary Cox🇨🇦 · Douglas M. Gingrich🇨🇦

    Greybody factors are computed for massless fields of spin 0, 1/2, 1, and 2 emitted from higher-dimensional non-commutative geometry inspired black holes. Short-range potentials are used with path-ordered matrix exponentials to numerically calculate transmission coefficients. The resulting absorption cross sections and emission spectra are computed on the brane and compared with the higher-dimensional Schwarzschild-Tangherlini black hole. A non-commutative black hole at its maximum temperature in seven extra dimensions will radiate a particle flux and power of 0.72-0.81 and 0.75-0.81, respectively, times lower than a Schwarzschild-Tangherlini black hole of the same temperature. A non-commutative black hole at its maximum temperature in seven extra dimensions will radiate a particle flux and power of 0.64-0.72 and 0.60-0.64, respectively, times lower than a Schwarzschild-Tangherlini black hole of the same mass.

    ↳ gr-qchep-phhep-thClass.Quant.Grav.(2023)·5 citations
13. 13*

    Towards a Muon Collider

    Carlotta Accettura · Dean Adams · Rohit Agarwal · Claudia Ahdida · Chiara Aimè · Nicola Amapane · David Amorim · Paolo Andreetto · Fabio Anulli · Robert Appleby · Artur Apresyan · Aram Apyan and 285 other authors

    A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work.

    ↳ physics.acc-phhep-exhep-phEPJC(2023)·408 citations
14. 14*

    On the Running of Gauge Couplings in String Theory

    Steven Abel🇬🇧 · Keith R. Dienes🇺🇸 · Luca A. Nutricati🇬🇧

    In this paper we conduct a general, model-independent analysis of the running of gauge couplings within closed string theories. Unlike previous discussions in the literature, our calculations fully respect the underlying modular invariance of the string and include the contributions from the infinite towers of string states which are ultimately responsible for many of the properties for which string theory is famous, including an enhanced degree of finiteness and UV/IR mixing. In order to perform our calculations, we adopt a formalism that was recently developed for calculations of the Higgs mass within such theories, and demonstrate that this formalism can also be applied to calculations of gauge couplings. In general, this formalism gives rise to an ``on-shell'' effective field theory (EFT) description in which the final results are expressed in terms of supertraces over the physical string states, and in which these quantities exhibit an EFT-like ``running'' as a function of an effective spacetime mass scale. We find, however, that the calculation of the gauge couplings differs in one deep way from that of the Higgs mass: while the latter results depend on purely on-shell supertraces, the former results have a different modular structure which causes them to depend on off-shell supertraces as well. In some regions of parameter space, our results demonstrate how certain expected field-theoretic behaviors can emerge from the highly UV/IR-mixed environment. In other situations, by contrast, our results give rise to a number of intrinsically stringy behaviors that transcend what might be expected within an effective field theory approach.

    ↳ hep-thhep-phPRD(2023)·22 citations
15. 15*

    Conformal Symmetries of the Strumia and Tetradis Metric

    Pantelis S. Apostolopoulos · Christos Tsipogiannis

    In a recent paper, a new conformally flat metric was introduced, describing an expanding scalar field in a spherically symmetric geometry. The spacetime can be interpreted as a Schwarzschild-like model with an apparent horizon surrounding the curvature singularity. For the above metric, we present the complete conformal Lie algebra consisting of a six-dimensional subalgebra of isometries (Killing Vector Fields or KVFs) and nine proper conformal vector fields (CVFs). An interesting aspect of our findings is that there exists a gradient (proper) conformal symmetry (i.e., its bivector vanishes) which verifies the importance of gradient symmetries in constructing viable cosmological models. In addition, the 9-dimensional conformal algebra implies the existence of constants of motion along null geodesics that allow us to determine the complete solution of null geodesic equations.

    ↳ gr-qchep-phhep-thPhys.Sci.Forum(2023)·0 citations
16. 16*

    Nucleon Sigma Terms with $N_f=2+1$ O($a$)-improved Wilson fermions

    Andria Agadjanov🇩🇪 · Dalibor Djukanovic🇩🇪 · Georg von Hippel🇩🇪 · Harvey B. Meyer🇩🇪 · Konstantin Ottnad🇩🇪 · Hartmut Wittig🇩🇪

    We present a lattice-QCD based analysis of the nucleon sigma terms using gauge ensembles with $N_f=2+1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions, with a complete error budget concerning excited-state contaminations, the chiral interpolation as well as finite-size and lattice spacing effects. We compute the sigma terms determined directly from the matrix elements of the scalar currents. The chiral interpolation is based on SU(3) baryon chiral perturbation theory using the extended on-mass shell renormalization scheme. For the pion nucleon sigma term, we obtain ${\sigma }_{\pi N}=(43.7\pm 3.6)$ MeV, where the error includes our estimate of the aforementioned systematics. The tension with extractions based on dispersion theory persists at the 2.4-$\sigma$ level. For the strange sigma term, we obtain a non-zero value, ${\sigma }_s=(28.6\pm 9.3)$ MeV.

    ↳ hep-lathep-phnucl-thPRL(2023)·45 citations
17. 17*

    Optimal Estimation of the Binned Mask-Free Power Spectrum, Bispectrum, and Trispectrum on the Full Sky: Scalar Edition

    Oliver H. E. Philcox🇺🇸

    We derive optimal estimators for the two-, three-, and four-point correlators of statistically isotropic scalar fields defined on the sphere, such as the Cosmic Microwave Background temperature fluctuations, allowing for arbitrary (linear) masking and inpainting schemes. In each case, we give the optimal unwindowed estimator (obtained via a maximum-likelihood prescription, with an associated Fisher deconvolution matrix), and an idealized form, and pay close attention to their efficient computation. For the trispectrum, we include both parity-even and parity-odd contributions, as allowed by symmetry. The estimators can include arbitrary weighting of the data (and remain unbiased), but are shown to be optimal in the limit of inverse-covariance weighting and Gaussian statistics. The normalization of the estimators is computed via Monte Carlo methods, with the rate-limiting steps (involving spherical harmonic transforms) scaling linearly with the number of bins. An accompanying code package, PolyBin, implements these estimators in Python, and we demonstrate the estimators' efficacy via a suite of validation tests.

    ↳ astro-ph.COgr-qchep-phhep-thPRD(2023)·30 citations
18. 18*

    Scattering amplitudes from dispersive iterations of unitarity

    Piotr Tourkine🇫🇷 · Alexander Zhiboedov🇨🇭

    We present and numerically implement a computational method to construct relativistic scattering amplitudes that obey analyticity, crossing, elastic and inelastic unitarity in three and four spacetime dimensions. The algorithm is based on the Mandelstam representation of the amplitude and iterations of unitarity. The input for the iterative procedure is given by the multi-particle double spectral density, the S-wave inelasticity, and the value of the amplitude at the crossing-symmetric point. The output, obtained at the fixed point of the iteration of unitarity, is a nonperturbative scattering amplitude. The amplitudes we obtain exhibit interesting features, such as non-zero particle production, intricate high-energy and near the two-particle threshold behavior. Scattering amplitudes obtained by initializing the iteration process with zero (or small) multi-particle input end up close to saturating the S-matrix bounds derived by other methods. There is a version of the iterative algorithm that is directly related to Feynman diagrams: it effectively re-sums infinitely many two-particle reducible planar Feynman graphs in the ${\varphi }^4$ theory, which remarkably produces a unitary nonperturbative scattering amplitude function. Finally, we discuss how the algorithm can be further refined by including multi-particle unitarity.

    ↳ hep-thhep-phJHEP(2023)·38 citations
19. 19*

    The magnificent ACT of flavor-specific neutrino self-interaction

    Anirban Das🇺🇸 · Subhajit Ghosh🇺🇸

    We revisit the cosmology of neutrino self-interaction and use the latest cosmic microwave background data from the Atacama Cosmology Telescope (ACT) and the Planck experiment to constrain the interaction strength. In both flavor-universal and nonuniversal coupling scenarios, we find that the ACT data prefers strong neutrino self-interaction that delays neutrino free streaming until just before the matter-radiation equality. When combined with the Planck 2018 data, the preference for strong interaction decreases due to the Planck polarization data. For the combined dataset, the flavor-specific interaction still provides a better fit to the CMB data than $\Lambda$CDM. This trend persists even when neutrino mass is taken into account and extra radiation is added. We also study the prospect of constraining such strong interaction by future terrestrial and space telescopes, and find that the upcoming CMB-S4 experiment will improve the upper limit on neutrino self-interaction by about a factor of three.

    ↳ astro-ph.COastro-ph.IMhep-phJCAP(2023)·31 citations
20. 20*

    Chirality Changing RG Flows: Dynamics and Models

    Yuri Shirman🇺🇸 · Shreya Shukla🇺🇸 · Michael Waterbury🇮🇱

    Chirality plays an important role in understanding the dynamics of quantum field theories. In this paper, we study the dynamics of models where renormalization group flows change the chiral structure of the theory. We introduce model building tools and construct models with a variety of chirality flows: from the appearance of new massless composite matter, to the development of mass gaps to completely general changes in the chiral matter content. The stability of chirally symmetric vacua is sensitive to the interplay between non-perturbative dynamics and deformations necessary to generate chirality flows. In particular, we show that chirality flows can be easily induced by deformations of s-confining models. On the other hand, in the absence of true s-confinement, the required deformations destabilize chirally symmetric ground states.

    ↳ hep-thhep-phJHEP(2023)·2 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.