Article
Astronomy & Astrophysics
Chien-Yeah Seng, Vincenzo Cirigliano, Xu Feng, Mikhail Gorchtein, Luchang Jin, Gerald A. Miller
Summary: Recent estimates suggest that the strong isospin-symmetry breaking (ISB) corrections to the Fermi matrix element in free neutron decay may be one order of magnitude larger than the naive estimate based on a theorem. To investigate this claim, we derive a general expression for the leading ISB correction to hadronic Fermi matrix elements, which can be computed from first principles. Our formalism opens up the possibility of determining this correction in the neutron sector with fully-controlled theory uncertainties.
Article
Astronomy & Astrophysics
Christopher Jung, Jan-Hendrik Otto, Ralf-Arno Tripolt, Lorenz von Smekal
Summary: This paper explores practicable ways for self-consistent calculations of spectral functions using analytically continued functional renormalization group (aFRG) flow equations. A particularly straightforward approach proposed is to include parametrizations of self-energies based on explicit analytic one-loop expressions. The results show the importance of self-consistency at all momenta in fixing the relation between particle masses and decay thresholds, offering a sound and practicable basis for calculations in more realistic effective theories.
Article
Physics, Particles & Fields
Luis Albino, Adnan Bashir, Bruno El-Bennich, Eduardo Rojas, Fernando E. Serna, Roberto Correa da Silveira
Summary: This study extends the investigation of transverse Ward-Fradkin-Green-Takahashi identities in QED to the equivalent gauge identities in QCD, revealing the constraints on the transverse quark-gluon vertex and deriving its associated scalar form factors. By studying the functional form of these form factors, significant chiral symmetry breaking and a mass gap in the quark are observed, leading to interesting implications such as the quark condensate and the pion's weak decay constant in the chiral limit.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Astronomy & Astrophysics
Kuan Zhang, Yuan-Yuan Li, Yi-Kai Huo, Andreas Schaefer, Peng Sun, Yi-Bo Yang
Summary: The study found that the cancellation of 1/a divergence deteriorates with decreasing lattice spacing, and the RI/MOM method leaves a linearly divergent residue when dealing with quasi-PDFs. Additionally, in the Landau gauge, the interaction between the Wilson link and the external state leads to a linear divergence that depends on the discretized fermion action.
Article
Astronomy & Astrophysics
M. Costa, G. Panagopoulos, H. Panagopoulos, G. Spanoudes
Summary: The study focuses on the Gluino-Glue operator in the context of Supersymmetric N = 1 Yang-Mills theory. It utilizes a Gauge-Invariant Renormalization Scheme to calculate Green's functions and conversion factors, allowing for analysis of low-lying bound states via numerical simulations.
Article
Astronomy & Astrophysics
Tyler D. Blanton, Stephen R. Sharpe
Summary: This paper discusses the scattering amplitudes of three-particle systems consisting of two identical particles and a different particle, deriving the formalism needed to extract these amplitudes. By using a relativistic formalism and diagrammatic analysis, the spectrum and scattering amplitudes of such systems are studied.
Article
Astronomy & Astrophysics
Zachary T. Draper, Stephen R. Sharpe
Summary: This study investigates pion-pion scattering in partially-quenched twisted-mass lattice QCD, revealing issues related to discretization errors and violation of unitarity. It proposes a systematic solution for reducing discretization errors by calculating the I = 2 scattering amplitude, while indicating that the error from the violation of unitarity is challenging to minimize in practice.
Article
Astronomy & Astrophysics
Szabolcs Borsanyi, Denes Sexty
Summary: The study utilizes the Density of States (DoS) method to simulate the topological susceptibility at high temperatures, revealing findings perfectly consistent with a free instanton gas.
Article
Physics, Particles & Fields
Malwin Niehus, Martin Hoferichter, Bastian Kubis
Summary: A formalism was proposed to extract the gamma pi -> pi pi chiral anomaly F-3 pi from lattice QCD calculations performed at larger-than-physical pion masses. By combining dispersion relations and effective field theory, recent lattice QCD calculations for gamma pi -> pi pi were extrapolated to the physical point, allowing the extraction of the radiative coupling of the rho(770) meson and the chiral anomaly F-3 pi = 38(16)(11) GeV-3 for the first time. The result is consistent with chiral predictions but has large uncertainties that may improve with future lattice-QCD computations.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Multidisciplinary
Jeremy R. Green, Andrew D. Hanlon, Parikshit M. Junnarkar, Hartmut Wittig
Summary: This study presents the first exploration of baryon-baryon interactions in the continuum limit of lattice QCD, revealing unexpectedly large lattice artifacts impacting the binding energy. By applying variational methods and Luscher's finite-volume quantization conditions, scattering phase shifts can be determined from the spectrum, leading to an estimate of the binding energy of the H dibaryon in three-flavor QCD.
PHYSICAL REVIEW LETTERS
(2021)
Article
Astronomy & Astrophysics
Constantia Alexandrou, Krzysztof Cichy, Martha Constantinou, Jeremy R. Green, Kyriakos Hadjiyiannakou, Karl Jansen, Floriano Manigrasso, Aurora Scapellato, Fernanda Steffens
Summary: The study calculates isovector unpolarized and helicity PDFs using lattice QCD, demonstrating the reliability of the continuum limit and improving understanding of lattice artifacts. Results show significant dependence on lattice spacing a, with better agreement with phenomenology observed through continuum extrapolation, particularly evident in the antiquark distribution at small momentum fraction x.
Article
Physics, Particles & Fields
Michal Czakon, Terry Generet, Alexander Mitov, Rene Poncelet
Summary: For the first time, NNLO QCD corrections to identified heavy hadron production at hadron colliders have been calculated, providing predictions for several differential distributions of B hadrons in t (t) over bar events at the LHC. The results may be extended to other processes, such as open or associated B and charm production, and there is potential for extracting heavy flavor fragmentation functions from LHC data.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Astronomy & Astrophysics
Xiang Gao, Andrew D. Hanlon, Nikhil Karthik, Swagato Mukherjee, Peter Petreczky, Philipp Scior, Shuzhe Shi, Sergey Syritsyn, Yong Zhao, Kai Zhou
Summary: In this study, lattice QCD calculations were performed to determine the valence parton distribution function of the pion, using next-to-next-leading-order perturbative QCD matching. The results are in good agreement with global fits to experimental data.
Article
Astronomy & Astrophysics
Andrew W. Jackura, Raul A. Briceno, Sebastian M. Dawid, Md Habib E. Islam, Connor McCarty
Summary: This study presents a simple scheme for solving relativistic integral equations for three-body amplitudes, exploring different solving strategies and discussing ways of incorporating bound-state pole contribution in the integral equations. The methods presented allow for determination of amplitudes above the three-body threshold and further the objective for directly extracting three-hadron scattering amplitudes from lattice QCD.
Article
Astronomy & Astrophysics
Yin Lin, Aaron S. Meyer, Steven Gottlieb, Ciaran Hughes, Andreas S. Kronfeld, James N. Simone, Alexei Strelchenko
Summary: This study continues the investigation of lattice-QCD baryon physics using staggered fermions, demonstrating how to calculate baryon matrix elements and verifying the methodology by calculating isovector charges. The results show the potential of highly improved staggered quarks for precision calculations of baryon properties.
Article
Physics, Particles & Fields
Claudio Bonanno, Claudio Bonati, Massimo D'Elia
Summary: The study simulated 4d SU(N) pure-gauge theories at large N using a parallel tempering scheme, reducing the autocorrelation time and refining the quartic coefficient of the theta-dependence of the vacuum energy b(2) with high accuracy. This approach achieved results comparable to the large-N limit of the topological susceptibility.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Multidisciplinary
Claudio Bonati, Andrea Pelissetto, Ettore Vicari
Summary: This study examines perturbations that disrupt gauge symmetries in lattice gauge theories, focusing on the Abelian-Higgs model. Particularly, it analyzes the effects of perturbations breaking gauge symmetries on critical behavior, computes relevant exponents for departure from critical behavior, and explores an effective enlargement of global symmetry in lattice AH models with broken gauge symmetry.
PHYSICAL REVIEW LETTERS
(2021)
Article
Mechanics
Claudio Bonati, Andrea Pelissetto, Ettore Vicari
Summary: We investigate the phase diagram and phase transitions in a three-dimensional model with global SU(N) symmetry, local U(1) symmetry, and without monopoles. Monte Carlo simulations for N = 2 and 25 reveal a finite-temperature transition related to the condensation of a local gauge-invariant order parameter. Results for the N = 2 model suggest a weak first-order transition, while results for the N = 25 model also indicate a first-order transition that weakens as the field-length fluctuations decrease.
JOURNAL OF STATISTICAL MECHANICS-THEORY AND EXPERIMENT
(2022)
Article
Physics, Particles & Fields
Andreas Athenodorou, Claudio Bonanno, Claudio Bonati, Giuseppe Clemente, Francesco D'Angelo, Massimo D'Elia, Lorenzo Maio, Guido Martinelli, Francesco Sanfilippo, Antonino Todaro
Summary: In this study, we compute the topological susceptibility of N-f = 2 + 1 QCD with physical quark masses in the high-temperature phase. The numerical simulations are performed on a space-time lattice, and the topological charge is defined using the staggered Dirac operator with spectral projectors. We find that our results for the susceptibility in the explored temperature range are partially in tension with previous determinations in the literature.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Astronomy & Astrophysics
Claudio Bonati, Alessio Franchi, Andrea Pelissetto, Ettore Vicari
Summary: We study the critical behavior of the three-dimensional Gross-Neveu (GN) model with Nf four-component Dirac fermionic flavors and quartic interactions, at the chiral 7L2 transition in the massless 7L2-symmetric limit. By performing Monte Carlo simulations and analyzing the numerical data, we obtain estimates of the critical exponents and compare them with large-Nf predictions from the continuum GN field theory. We observe substantial agreement, confirming that lattice GN models provide a nonperturbative realization of the GN quantum field theory.
Article
Materials Science, Multidisciplinary
Claudio Bonati, Niccolo Francini
Summary: We examine the phase diagram and phase transitions of the three-dimensional multicomponent lattice Higgs model with noncompact Abelian discrete groups. For a sufficiently large number of scalar fields N, the model with noncompact U(1) gauge group undergoes a continuous transition associated with the charged fixed point of the continuous Abelian Higgs field theory. Our findings show that in the model with gauge group Z(nc)q equivalent to 2 pi Z/q, only critical transitions in the orthogonal universality classes occur for small values of N, while a symmetry expansion to the continuous Abelian Higgs universality class occurs when q is greater than or equal to 5 and N is large enough.
Article
Physics, Fluids & Plasmas
Claudio Bonati, Andrea Pelissetto, Ettore Vicari
Summary: This study investigates the phase diagram and phase transitions of three-dimensional lattice gauge-Higgs models obtained by gauging the ZN subgroup of the global Zq invariance group of the Zq clock model. The phase diagram consists of three different phases separated by distinct transition lines. The critical behavior along two transition lines characterized by the ordering of the scalar field is studied. The results confirm the theoretical predictions and show that the transitions belong to the Ising and O(2) universality classes.
Article
Materials Science, Multidisciplinary
Claudio Bonati, Andrea Pelissetto, Ettore Vicari
Summary: Investigated the multicritical behavior of the three-dimensional Z(2) gauge Higgs model at the multicritical point, and found that the multicritical XY behavior at the MCP is controlled by the duality properties of the model and shows an effective enlargement of the symmetry to the continuous group O(2).
Article
Physics, Fluids & Plasmas
Claudio Bonati, Alessio Franchi
Summary: We investigate the interplay between local and global symmetries in two-dimensional lattice scalar theories. We find that the continuum limit of these models corresponds to the gauged nonlinear ?? model field theory associated with the real Grassmannian manifold in some cases. Monte Carlo simulations and finite-size scaling analyses confirm the emergence of the color-flavor reflection symmetry in the scaling limit and support the identification of the continuum limit.
Article
Materials Science, Multidisciplinary
Claudio Bonati, Andrea Pelissetto, Ettore Vicari
Summary: This study investigates the continuum limit of the three-dimensional multicomponent Abelian-Higgs field theory in statistical lattice gauge models, and finds that it characterizes the universal behavior at critical transitions in these models.
Article
Physics, Fluids & Plasmas
Claudio Bonati, Alessio Franchi, Andrea Pelissetto, Ettore Vicari
Summary: The study focuses on three-dimensional lattice SU(N-c) gauge theories with complex scalar fields, investigating the Higgs phases, critical behaviors, and the role of quartic scalar potential in determining symmetries. The numerical results suggest the existence of charged critical behaviors for N-f > N-f*, with 20 < N-f* < 40 in the case of N-c = 2.
Article
Physics, Fluids & Plasmas
Claudio Bonati, Andrea Pelissetto, Ettore Vicari
Summary: We studied the effects of gauge-symmetry breaking (GSB) perturbations in three-dimensional lattice gauge theories with scalar fields. The gauge symmetry proves to be quite robust with respect to the GSB perturbation, and we determined the phase diagram of the model which includes one disordered phase and two ordered phases. The behavior at the CP1 gauge-symmetric critical point substantially differs from that at transitions in which gauge correlations become critical.
Article
Astronomy & Astrophysics
Claudio Bonati, Marco Cardinali, Massimo D'Elia, Matteo Giordano, Fabrizio Mazziotti
Summary: The study shows that the reconfinement phase transition in trace deformed SU(3) Yang-Mills theory is first order, similar to the standard thermal phase transition. The behavior of thermal monopoles and the localization properties of Dirac eigenmodes are investigated, indicating a strict link between them in both reconfinement and standard confinement transitions.
Article
Materials Science, Multidisciplinary
Claudio Bonati, Andrea Pelissetto, Ettore Vicari
Summary: The study investigates a noncompact lattice formulation of three-dimensional electrodynamics with N-component complex scalar fields, showing a phase diagram with three distinct phases: Coulomb phase, Higgs phase, and molecular phase separated by transition lines meeting at a multicritical point. The transitions are described by various continuum field theories with explicit or implicit gauge fields, and the numerical results are consistent with renormalization-group predictions for consecutive Coulomb-to-Higgs transitions.
Article
Astronomy & Astrophysics
Claudio Bonati, Alessio Franchi, Andrea Pelissetto, Ettore Vicari
Summary: The study focuses on a two-dimensional lattice SO(N-c) gauge theory with two scalar flavors, obtained by partially gauging a maximally symmetric scalar model. It is shown that the theory undergoes finite-temperature Berezinskii-Kosterlitz-Thouless transitions and the critical properties are determined through Monte Carlo data analysis.