Wed·Dec 21, 2022Wednesday·December 21, 2022

1. 01*

   Accessing proton GPDs in asymmetric frames: Numerical implementation

   Martha Constantinou🇺🇸 · Shohini Bhattacharya🇺🇸 · Krzysztof Cichy🇵🇱 · Jack Dodson🇺🇸 · Xiang Gao🇺🇸 · Andreas Metz🇺🇸 · Swagato Mukherjee🇺🇸 · Aurora Scapellato🇺🇸 · Fernanda Steffens🇩🇪 · Yong Zhao🇺🇸

   In this work, we present a numerical investigation of a novel Lorentz-covariant parametrization to extract $x$-dependent GPDs using off-forward matrix elements of momentum-boosted hadrons coupled to non-local operators. The novelty of the method is the implementation of an asymmetric frame for the momentum transfer between the initial and final hadron state and the parametrization of the matrix elements into Lorentz-invariant amplitudes. The amplitudes can then be related to the standard light-cone GPDs. GPDs are defined in the symmetric frame, which requires a separate calculation for each value of the momentum transfer, increasing the computational cost significantly. The proposed method is powerful, as one can extract the GPDs at multiple values of the momentum transfer at the computational cost of a single value. For this proof-of-concept calculation, we use one ensemble of $N_f=2+1+1$ twisted mass fermions and a clover improvement with a pion mass of 260 MeV to calculate the proton unpolarized GPDs.

   hep-latPoS(2023)·9 citations
2. 02*

   Two-loop matching of the chromo-magnetic dipole operator with the gradient flow

   J. Borgulat🇩🇪 · R. Harlander🇩🇪 · M.D. Rizik🇺🇸 · A. Shindler🇺🇸

   The chromo-magnetic dipole operator is expressed in terms of operators at finite flow time in the gradient-flow formalism. The matching coefficients are evaluated through next-to-next-to-leading order QCD.

   hep-lathep-phPoS(2023)·9 citations
3. 03*

   QCD thermodynamics with stabilized Wilson fermions

   Rocco Francesco Basta🇩🇪 · Bastian B. Brandt🇩🇪 · Francesca Cuteri🇩🇪 · Gergely Endrődi🇩🇪 · Anthony Francis🇹🇼

   Stabilized Wilson fermions are a reformulation of Wilson clover fermions that incorporates several numerical stabilizing techniques, but also a local change of the fermion action - the original clover term being replaced with an exponentiated version of it. We intend to apply the stabilized Wilson fermions toolbox to the thermodynamics of QCD, starting on the $N_f=3$ symmetric line on the Columbia plot, and to compare the results with those obtained with other fermion discretizations.

   hep-latPoS(2023)·2 citations
4. 04*

   Mass and isovector matrix elements of the nucleon at zero-momentum transfer

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

   We present the current status of our analysis of nucleon structure observables including isovector charges and twist-2 matrix elements as well as the nucleon mass. Results are computed on a large set of CLS $N_f=2+1$ gauge ensembles with $M_{\pi }\approx 0.130\mathrm{MeV}\dots 350\mathrm{MeV}$, four values of the lattice spacing $a=0.05\mathrm{fm}\dots 0.09\mathrm{fm}$ and covering a large range of physical volumes. Compared to the results presented at last year's conference we have added data on a very fine and large box at small light quark mass ($T\times L^3=192\times 96^3$, $M_{\pi }=172\mathrm{MeV}$, $a=0.05\mathrm{fm}$). Additional (intermediate) source-sink separations have been computed on the coarser ensembles, further increasing effective statistics and allowing for a more fine-grained control in the treatment of the excited-state contamination. Excited states in the nucleon matrix elements are tamed by a simultaneous, two-state fit ansatz using the summation method.

   hep-latPoS(2023)·8 citations
5. 05*

   Three-pion effects in $K^0-{\bar{K}}^0$ mixing

   Andrew W. Jackura🇺🇸 · Raúl A. Briceńo🇺🇸 · Maxwell T. Hansen🇬🇧

   The rate of mixing between a neutral kaon and an anti-kaon ($K^0-{\bar{K}}^0$) is given, in part, by a long-range matrix element, defined with two insertions of the weak Hamiltonian separated by physical, Minkowski time evolution. For physical quark masses, the kaon mass lies above the two- and three-pion thresholds and, as a result, this long-range matrix element receives contributions from intermediate on-shell $2\pi$ and $3\pi$ states. These contributions cannot easily be captured in a finite Euclidean spacetime, meaning that such matrix elements are not directly accessible via lattice QCD. In this talk, we present a strategy for combining quantities that can be extracted in numerical lattice QCD calculations in order to reproduce the physical, infinite-volume long-range amplitude for $K^0-{\bar{K}}^0$. The key novelty relative to published work is that we fully include the effects of three-particle states that were previously neglected. The strategy is built on existing formalism for long-range matrix elements with two-particle intermediate states, together with the relativistic-field-theory finite-volume formalism for extracting three-hadron weak decays.

   hep-latPoS(2023)·9 citations
6. 06*

   Isothermal and isentropic speed of sound in (2+1)-flavor QCD at non-zero baryon chemical potential

   D. A. Clarke🇺🇸

   Recently interest in calculations of the speed of sound in QCD under conditions like constant temperature $c_T^2$ or constant entropy per net baryon number $c_s^2$ arose in the discussion of experimental results coming from heavy ion experiments. It has been stressed that the former in particular is closely related to higher order cumulants of conserved charge fluctuations that are calculated in lattice QCD. We present here results on $c_T^2$ and $c_s^2$ and compare results at vanishing strangeness chemical potential and vanishing net strangeness number with hadron resonance gas model calculations. We stress the difference of both observables at low temperature arising from the light meson sector, which does not contribute to $c_T^2$.

   hep-latPoS(2023)·4 citations
7. 07*

   The isentropic equation of state of (2+1)-flavor QCD: An update based on high precision Taylor expansion and Padé-resummed expansion at finite chemical potentials

   Jishnu Goswami🇯🇵

   The HotQCD Collaboration performed Taylor expansion calculations in 2017 for the pressure, energy density, and entropy density at non-zero chemical potentials up to the $6^{th}$ order. Since then, they have significantly improved the statistics for lattices with temporal extents of $N_{\tau }=8$ and $12$, and have also included results for $N_{\tau }=16$ that were not previously available. They have also calculated the $8^{th}$-order expansion coefficients for $N_{\tau }=8$. These calculations showed that the Taylor series expansion for the pressure is accurate up to ${\mu }_B/T\le 2.5$. In this study, we use the high-statistics results on Taylor expansion coefficients, calculated with HISQ fermions and extrapolated to the continuum limit, to determine the QCD equation of state under conditions relevant for hot and dense matter produced in heavy ion collisions. We also calculate the energy density and pressure along lines of constant entropy per net baryon number.

   hep-lathep-phnucl-thPoS(2023)·6 citations
8. 08*

   Finite temperature QCD phase transition with 3 flavors of Möbius domain wall fermions

   Yu Zhang🇯🇵 · Yasumichi Aoki🇯🇵 · Shoji Hashimoto🇯🇵 · Issaku Kanamori🇯🇵 · Takashi Kaneko🇯🇵 · Yoshifumi Nakamura🇯🇵

   We investigate the finite temperature QCD phase transition with three degenerate quark flavors using Möbius domain wall fermions. To explore the order of phase transition on the lower left corner of Columbia plot and if possible, to locate the critical endpoint we performed simulations at temperatures around 181 and 121 MeV with lattice spacing $a=0.1361(20)$ fm corresponding to temporal lattice extent $N_{\tau }=8,12$ with varying quark mass for two different volumes with aspect ratios $N_{\sigma }/N_{\tau }$ ranging from 2 to 3. By analyzing the volume and mass dependence of the chiral condensate, disconnected chiral susceptibility and Binder cumulant we find that there is a crossover at $m_q^{\overline{\mathrm{MS}}}(2\mathrm{GeV})\sim 44\mathrm{MeV}$ for ${\mathrm{T}}_{\mathrm{pc}}\sim$ 181 MeV, At temperature 121 MeV, the binder cumulant suggests a crossover at $m_q^{\overline{\mathrm{MS}}}(2\mathrm{GeV})\sim 3.7\mathrm{MeV}$, although a study of volume dependence would be important to confirm this.

   hep-lathep-phhep-thnucl-thPoS(2023)·13 citations
9. 09*

   B Meson Decay Constants Using Relativistic Heavy Quarks

   Matthew Black🇩🇪 · Oliver Witzel🇩🇪

   We present an update on ongoing work to extract pseudoscalar and vector decay constants for $B^{(\ast )}$, $B_s^{(\ast )}$ and $B_c^{(\ast )}$ mesons and determine phenomenologically-interesting ratios such as $f_{B_s}/f_B$ or $f_{B^{\ast }}/f_B$. Our calculation is based on ${\mathrm{N}}_{\mathrm{f}}=2+1$ dynamical flavour gauge field ensembles generated by the RBC/UKQCD collaborations using domain-wall fermions and the Iwasaki gauge action. Using domain-wall light, strange, and charm quarks and relativistic $b$ quarks, we obtain results at multiple lattice spacings and valence quark masses.

   hep-latPoS(2023)·3 citations
10. 10*

    The emergence of expanding space-time in a novel large-$N$ limit of the Lorentzian type IIB matrix model

    Mitsuaki Hirasawa🇮🇹 · Konstantinos N. Anagnostopoulos🇬🇷 · Takehiro Azuma🇯🇵 · Kohta Hatakeyama🇯🇵 · Jun Nishimura🇯🇵 · Stratos Kovalkov Papadoudis🇬🇷 · Asato Tsuchiya🇯🇵

    The Lorentzian type IIB matrix model is a promising candidate for a non-perturbative formulation of superstring theory. However, it was found recently that a Euclidean space-time appears in the conventional large-$N$ limit. In this work, we add a Lorentz invariant mass term to the original model and consider a limit, in which the coefficient of the mass term vanishes at large $N$. By performing complex Langevin simulations to overcome the sign problem, we observe the emergence of expanding space-time with the Lorentzian signature.

    hep-latgr-qchep-thPoS(2023)·6 citations
11. 11*

    Lattice gauge ensembles and data management

    Gunnar Bali (1)🇩🇪 · Ryan Bignell (2)🇬🇧 · Anthony Francis (3)🇹🇼 · Steven Gottlieb (4)🇺🇸 · Rajan Gupta (5)🇺🇸 · Issaku Kanamori (6)🇯🇵 · Bartosz Kostrzewa (7)🇩🇪 · Andrey Yu. Kotov (8)🇩🇪 · Yoshinobu Kuramashi (9)🇯🇵 · Robert Mawhinney (10)🇺🇸 · Christian Schmidt (11)🇩🇪 · Wolfgang Söldner (1)🇩🇪 · Peng Sun (12) ((1) Universität Regensburg, (2) Swansea University, (3) National Yang Ming Chiao Tung University, (4) Indiana University, (5) Los Alamos National Laboratory, (6) RIKEN Center for Computational Science, (7) Universität Bonn, (8) Forschungszentrum Jülich, (9) University of Tsukuba, (10) Columbia University, (11) Universität Bielefeld, (12) Chinese Academy of Sciences)🇨🇳

    The generation of ensembles of gauge configurations is a considerable expense. The preservation and curation of these ensembles constitutes a valuable shared resource for the lattice field theory community. The organizers of Lattice 2022 dedicated a parallel session to the presentation of gauge ensembles and their generation, plans for ensemble publication and data management/storage activities of different collaborations. A summary of the twelve contributions is presented here.

    hep-latPoS(2022)·11 citations
12. 12*

    Parallel tempering algorithm applied to the deconfinement transition of quenched QCD

    Ruben Kara🇩🇪 · Szabolcs Borsanyi🇩🇪 · Zoltan Fodor🇩🇪 · Daniel A. Godzieba🇺🇸 · Paolo Parotto🇺🇸 · Denes Sexty🇦🇹

    QCD with infinite heavy quark masses exhibits a first-order thermal transition which is driven by the spontaneous breaking of the global ${\mathcal{Z}}_3$ center symmetry. We analyze the corresponding order parameter, namely the Polyakov loop and its moments, and show, with a rigorous finite size scaling, that in the continuum limit the transition is of first order. We show that the use of a parallel tempering algorithm can significantly reduce the large auto-correlation times which are mainly caused by the supercritical slowing down. As a result, we calculate the transition temperature $w_0{T}_c$ with per-mill precision, and the latent heat, carrying out controlled continuum and infinite volume extrapolations.

    hep-latPoS(2023)·2 citations
13. 13*

    One flavour adjoint QCD with overlap fermions

    G. Bergner🇩🇪 · I. Soler Calero🇩🇪 · J. C. Lopez🇩🇪 · S. Piemonte🇩🇪

    The infrared effective theory of adjoint QCD with one Dirac flavour is still under debate. The theory could be confining, conformal, or with a massless fermion in the infrared. The study of chiral symmetry seems to be important to answer this question. While previous investigations have considered Wilson fermions, we present here the first results for this theory based on overlap fermions to avoid explicit chiral symmetry breaking. These indicate spontaneous chiral symmetry breaking by the formation of a fermion condensate. We have also investigated the running coupling of the theory, which indicates no infrared conformality in the energy region we have explored.

    hep-latPoS(2023)·3 citations
14. 14*

    $B\to D^{(\ast )}\ell \nu$ at non-zero recoil

    Alejandro Vaquero🇺🇸

    $B$ anomalies play a prominent role in Beyond the Standard Model (BSM) physics searches. In particular, the long standing tension between the inclusive and the exclusive determinations of the CKM matrix element $|V_{cb}|$ and the current tensions in the $R(D)$--$R(D^{\ast })$ plane between theory and experiment have brought the $B\to D^{(\ast )}\ell \nu$ semileptonic processes to the spotlight. Existing lattice-QCD calculations of the $B\to D\ell \nu$ form factors at non-zero recoil are being complemented with very recent developments in the $B\to D^{\ast }\ell \nu$ channel. In this review I discuss recent progress in lattice calculations of $B\to D^{(\ast )}\ell \nu$, as well as the implications of these results for high precision determinations of $|V_{cb}|$ and the Lepton Flavor Universality (LFU) ratios $R(D^{(\ast )})$.

    hep-lathep-phPoS(2022)·6 citations
15. 15*

    Quark mass dependence of hadron resonances

    F. Gil-Domínguez🇪🇸 · R. Molina🇪🇸

    We study the dependence of the $D_{s0}(2317)$ mass on the light quark mass through the analysis of data from QCD lattice simulations. Combining HH$\chi$PT and model selection tools as the LASSO method we fit the lattice data of the low-lying charmed mesons masses, obtaining their extrapolation to the physical point and extracting results for the quark mass dependence of the exotic resonances $D_{s0}(2317)$ and $D_{s1}(2460)$, taking as input the energy levels from a lattice simulation.

    hep-lathep-phPoS(2023)·0 citations
16. 16*

    Pseudoscalar-pole contributions to the muon $g-2$ at the physical point

    Sebastian Burri🇨🇭 · Gurtej Kanwar🇨🇭 · Constantia Alexandrou🇨🇾 · Simone Bacchio🇨🇾 · Georg Bergner🇩🇪 · Jacob Finkenrath🇨🇾 · Andrew Gasbarro🇨🇭 · Kyriakos Hadjiyiannakou🇨🇾 · Karl Jansen🇩🇪 · Bartosz Kostrzewa🇩🇪 · Giannis Koutsou🇨🇾 · Konstantin Ottnad🇩🇪 and 5 other authors

    Pseudoscalar-pole diagrams are an important component of estimates of the hadronic light-by-light (HLbL) contribution to the muon $g-2$. We report on our computation of the transition form factors ${\mathcal{F}}_{P\to {\gamma }^{\ast }{\gamma }^{\ast }}$ for the neutral pseudoscalar mesons $P={\pi }^0$ and $\eta$. The calculation is performed using twisted-mass lattice QCD with physical quark masses. On the lattice, we have access to a broad range of (space-like) photon four-momenta and therefore produce form factor data complementary to the experimentally accessible single-virtual direction, which directly leads to an estimate of the pion- and $\eta$-pole components of the muon $g-2$. For the pion, our result for the $g-2$ contribution in the continuum is comparable with previous lattice and data-driven determinations, with combined relative uncertainties below $10\%$. For the $\eta$ meson, we report on a preliminary determination from a single lattice spacing.

    hep-latPoS(2023)·5 citations
17. 17*

    Exploring gauge theories with adjoint matter on the lattice

    Georg Bergner🇩🇪 · Gernot Münster🇩🇪 · Stefano Piemonte🇩🇪

    We review our efforts in investigating gauge theories with fermions in the adjoint representation of the gauge group by means of numerical simulations. These theories have applications in possible extensions of the Standard Model of particle physics, being a core part of supersymmetric gauge theories. They also play an important role in uncovering fundamental properties of strongly interacting theories due to distinct features, such as a substantially different phase diagram.

    hep-latUniverse(2022)·10 citations
18. 18*

    Supercurrent renormalization of $\mathcal{N}=1$ supersymmetric Yang-Mills theory on the lattice

    Georg Bergner🇩🇪 · Marios Costa🇨🇾 · Haralambos Panagopoulos🇨🇾 · Stefano Piemonte🇩🇪 · Ivan Soler🇩🇪 · Gregoris Spanoudes🇨🇾

    Supersymmetry on the lattice is explicitly broken by the gluino mass and lattice artifacts. However, it can be restored in the continuum limit by fine tuning the parameters based on the renormalized Ward identities. On the renormalization step not only the mass but also the renormalization of the supercurrent needs to be addressed. Here we present a lattice investigation to obtain the renormalization factors of the supercurrent for $\mathcal{N}$=1 Super-Yang Mills theory in a gauge invariant renormalization scheme. We also provide the conversion factors which are necessary in order to translate our results to the more standard $\overline{\text{MS}}$ scheme.

    hep-latPoS(2023)·2 citations
19. 19*

    Topological Dimensions from Disorder and Quantum Mechanics?

    Ivan Horváth🇨🇿 · Peter Markoš🇸🇰

    We have recently shown that critical Anderson electron in $D=3$ dimensions effectively occupies a spatial region of infrared (IR) scaling dimension $d_{\text{IR}}\approx 8/3$. Here we inquire about the dimensional substructure involved. We partition space into regions of equal quantum occurrence probability, such that points comprising a region are of similar relevance, and calculate the IR scaling dimension $d$ of each. This allows us to infer the probability density $p(d)$ for dimension $d$ to be accessed by electron. We find that $p(d)$ has a strong peak at $d$ very close to 2. In fact, our data suggests that $p(d)$ is non-zero on the interval $[d_{\text{min}},d_{\text{max}}]\approx [4/3,8/3]$ and may develop a discrete part ($\delta$-function) at $d=2$ in infinite-volume limit. The latter invokes the possibility that combination of quantum mechanics and pure disorder can lead to emergence of topological dimensions. Although $d_{\text{IR}}$ is based on effective counting of which $p(d)$ has no a priori knowledge, $d_{\text{IR}}\ge d_{\text{max}}$ is an exact feature of the ensuing formalism. Possible connection of our results to recent findings of $d_{\text{IR}}\approx 2$ in Dirac near-zero modes of thermal quantum chromodynamics is emphasized.

    ↳ cond-mat.dis-nnhep-lathep-thnucl-th+1Entropy(2023)·2 citations
20. 20*

    Short \& intermediate distance HVP contributions to muon g-2: SM (lattice) prediction versus $e^{+}{e}^{-}$ annihilation data

    Constantia Alexandrou🇨🇾 · Simone Bacchio🇨🇾 · Petros Dimopoulos🇮🇹 · Jacob Finkenrath🇨🇾 · Roberto Frezzotti🇮🇹 · Giuseppe Gagliardi🇮🇹 · Marco Garofalo🇩🇪 · Kyriakos Hadjiyiannakou🇨🇾 · Bartosz Kostrzewa🇩🇪 · Karl Jansen🇩🇪 · Vittorio Lubicz🇮🇹 · Marcus Petschlies🇩🇪 and 4 other authors

    We present new lattice results of the ETM Collaboration, obtained from extensive simulations of lattice QCD with dynamical up, down, strange and charm quarks at physical mass values, different volumes and lattice spacings, concerning the SM prediction for the so-called intermediate window (W) and short-distance (SD) contributions to the leading order hadronic vacuum polarization (LO-HVP) term of the muon anomalous magnetic moment, $a_{\mu }$. Results for $a_{\mu }^{\mathrm{LO}-\mathrm{HVP},\mathrm{W}}$ and $a_{\mu }^{\mathrm{LO}-\mathrm{HVP},\mathrm{SD}}$, besides representing a step forward to a complete lattice computation of $a_{\mu }^{\mathrm{LO}-\mathrm{HVP}}$ and a useful benchmark among lattice groups, are compared here with their dispersive counterparts based on experimental data for $e^{+}{e}^{-}$ into hadrons. The comparison confirms the tension in $a_{\mu }^{\mathrm{LO}-\mathrm{HVP},\mathrm{W}}$, already noted in 2020 by the BMW Collaboration, while showing no tension in $a_{\mu }^{\mathrm{LO}-\mathrm{HVP},\mathrm{SD}}$.

    ↳ hep-phhep-lat4 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.