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We present the first direct calculation of the transversity parton distribution function within the nucleon from lattice QCD. The calculation is performed using simulations with the light quark mass fixed to its physical value and at one…

High Energy Physics - Lattice · Physics 2018-12-06 Constantia Alexandrou , Krzysztof Cichy , Martha Constantinou , Karl Jansen , Aurora Scapellato , Fernanda Steffens

We present results for hadrons containing a strange quark in quenched lattice QCD. We calculate masses and decay constants using 60 gauge configurations with an O(a)-improved fermion action at beta = 6.2. Using the rho mass to set the…

High Energy Physics - Lattice · Physics 2007-05-23 D. G. Richards

We present the unpolarized and helicity parton distribution functions calculated within lattice QCD simulations using physical values of the light quark mass. Non-perturbative renormalization is employed and the lattice data are converted…

High Energy Physics - Lattice · Physics 2018-09-19 Constantia Alexandrou , Krzysztof Cichy , Martha Constantinou , Karl Jansen , Aurora Scapellato , Fernanda Steffens

We present results for the flavor non-singlet u-d parton distribution functions within the nucleon using the quasi-PDF approach. The lattice calculation is performed by employing the twisted mass formulation and two gauge ensembles, having…

We calculate the strange quark content of the nucleon in 2+1-flavor lattice QCD. Chirally symmetric overlap fermion formulation is used to avoid the contamination from up and down quark contents due to an operator mixing between strange and…

High Energy Physics - Lattice · Physics 2015-03-20 JLQCD Collaboration , H. Ohki , K. Takeda , S. Aoki , S. Hashimoto , T. Kaneko , H. Matsufuru , J. Noaki , T. Onogi

A lattice QCD calculation of the proton matrix element of the flavor singlet axial-vector current is reported. Both the connected and disconnected contributions are calculated, for the latter employing the variant method of wall source…

High Energy Physics - Lattice · Physics 2009-10-28 M. Fukugita , Y. Kuramashi , M. Okawa , A. Ukawa

Generalized parton distributions (GPDs) are among the most fundamental quantities for describing the internal structure of hadrons. In this work, we present results on isovector GPDs of the proton obtained within lattice Quantum…

We present the first exploratory lattice QCD calculation of the pion valence quark distribution extracted from spatially separated current-current correlations in coordinate space. We show that an antisymmetric combination of vector and…

High Energy Physics - Lattice · Physics 2019-04-17 Raza Sabbir Sufian , Joseph Karpie , Colin Egerer , Kostas Orginos , Jian-Wei Qiu , David G. Richards

We present a calculation of the scalar, vector, and tensor form factors for the pion and kaon in lattice QCD. We use an ensemble of two degenerate light, a strange and a charm quark ($N_f=2+1+1$) of maximally twisted mass fermions with…

Information about double parton distributions (DPDs) can be obtained by calculating four-point functions on the lattice. We continue our study on the first DPD Mellin moment of the unpolarized proton by considering interference effects…

High Energy Physics - Lattice · Physics 2022-11-28 Christian Zimmermann , Daniel Reitinger

In this contribution, results from $N_f=2$ lattice QCD simulations at one lattice spacing using twisted mass fermions with a clover term at the physical pion mass are presented. The mass splitting between charged and neutral pions…

We report a state-of-the-art lattice calculation of the isovector quark transversity distribution of the proton at the physical pion mass. Within the framework of large-momentum effective theory (LaMET), we compute the transversity…

High Energy Physics - Lattice · Physics 2018-10-12 Yu-Sheng Liu , Jiunn-Wei Chen , Luchang Jin , Ruizi Li , Huey-Wen Lin , Yi-Bo Yang , Jian-Hui Zhang , Yong Zhao

We present results for the $x$ dependence of the unpolarized, helicity, and transversity isovector quark distributions in the proton using lattice QCD, employing the method of quasi-distributions proposed by Ji in 2013. Compared to a…

High Energy Physics - Lattice · Physics 2016-09-02 Constantia Alexandrou , Krzysztof Cichy , Kyriakos Hadjiyiannakou , Karl Jansen , Fernanda Steffens , Christian Wiese

We review two lattice calculations involving charm hadrons: a determination of the vector and scalar form factors of the semileptonic $D \to \pi \ell \nu$ decays, which are relevant for the extraction of the CKM matrix element $\lvert…

High Energy Physics - Lattice · Physics 2017-02-02 Lorenzo Riggio , Giorgio Salerno

We present a high precision lattice calculation of the average up/down, strange and charm quark masses performed with Nf=2 twisted mass Wilson fermions. The analysis includes data at four values of the lattice spacing and pion masses as low…

High Energy Physics - Lattice · Physics 2015-03-17 ETM Collaboration , B. Blossier , P. Dimopoulos , R. Frezzotti , V. Lubicz , M. Petschlies , F. Sanfilippo , S. Simula , C. Tarantino

We report on numerical lattice QCD calculations of some of the low moments of the nucleon structure functions. The calculations are carried out with gauge configurations generated by the RBC and UKQCD collaborations with (2+1)-flavors of…

High Energy Physics - Lattice · Physics 2014-11-20 Yasumichi Aoki , Tom Blum , Huey-Wen Lin , Shigemi Ohta , Shoichi Sasaki , Robert Tweedie , Takeshi Yamazaki , James Zanotti

We show the first results for parton distribution functions within the proton at the physical pion mass, employing the method of quasi-distributions. In particular, we present the matrix elements for the iso-vector combination of the…

We present a state-of-the-art calculation of the isovector quark helicity Bjorken-$x$ distribution in the proton using lattice-QCD ensembles at the physical pion mass. We compute quasi-distributions at proton momenta $P_z \in \{2.2, 2.6,…

High Energy Physics - Lattice · Physics 2019-01-29 Huey-Wen Lin , Jiunn-Wei Chen , Xiangdong Ji , Luchang Jin , Ruizi Li , Yu-Sheng Liu , Yi-Bo Yang , Jian-Hui Zhang , Yong Zhao

We compute the helicity-dependent strange quark distribution in the proton in the framework of chiral effective theory. Starting from the most general chiral SU(3) Lagrangian that respects Lorentz and gauge invariance, we derive the…

High Energy Physics - Phenomenology · Physics 2021-01-01 X. G. Wang , Chueng-Ryong Ji , W. Melnitchouk , Y. Salamu , A. W. Thomas , P. Wang

Moments of the quark density, helicity, and transversity distributions are calculated in unquenched lattice QCD. Calculations of proton matrix elements of operators corresponding to these moments through the operator product expansion have…