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Related papers: Pion form factor with chirally improved fermions

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Using Nf=2+1+1 lattice QCD, we determine the fermionic connected contributions to the second and third moment of the pion PDF. Based on gauge configurations from the European Twisted Mass Collaboration, chiral and continuum extrapolations…

High Energy Physics - Lattice · Physics 2021-02-22 M. Oehm , C. Alexandrou , M. Constantinou , K. Jansen , G. Koutsou , B. Kostrzewa , F. Steffens , C. Urbach , S. Zafeiropoulos

We present results for the isovector nucleon form factors measured on a $96^4$ lattice at almost the physical pion mass with a lattice spacing of 0.085 fm in 2+1 flavor QCD. The configurations are generated with the stout-smeared…

High Energy Physics - Lattice · Physics 2018-10-24 Ken-Ichi Ishikawa , Yoshinobu Kuramashi , Shoichi Sasaki , Natsuki Tsukamoto , Akira Ukawa , Takeshi Yamazaki

The charge, magnetic and quadrupole form factors of vector mesons and the charge form factor of pseudo-scalar mesons are calculated in quenched lattice QCD. The charge radii and magnetic moments are derived. The quark sector contributions…

High Energy Physics - Lattice · Physics 2010-03-04 B. G. Lasscock , J. Hedditch , D. B. Leinweber , A. G. Williams

We report on our calculation of pion and kaon form factors in three-flavor QCD using the overlap quark action. Gauge ensembles are generated on a 16^3 \times 48 lattice at a lattice spacing of 0.11 fm with pion masses down to 310 MeV.…

High Energy Physics - Lattice · Physics 2010-12-02 JLQCD Collaboration , T. Kaneko , S. Aoki , G. Cossu , H. Fukaya , S. Hashimoto , J. Noaki , T. Onogi

We present results on the nucleon electromagnetic form factors within lattice QCD using two flavors of degenerate twisted mass fermions. Volume effects are examined using simulations at two volumes of spatial length L=2.1 fm and L=2.8 fm.…

High Energy Physics - Lattice · Physics 2015-03-18 C. Alexandrou , M. Brinet , J. Carbonell , M. Constantinou , P. A. Harraud , P. Guichon , K. Jansen , T. Korzec , M. Papinutto

From recent analysis of the $\pi\pi$ scattering amplitude, it has been claimed that there exists a broad and light $\sigma$ meson. However, if this meson really exists, it must also appear in other observables such as the pion scalar form…

High Energy Physics - Phenomenology · Physics 2008-11-26 Torben Hannah

We use recent data on K^+ -> pi^+e^+e^-, together with known values for the pion form factor, to derive the kaon electromagnetic form factor for 0 <q^2 <0.125 (GeV/c)^2. The results are then compared with predictions of the Linear sigma…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Lowe , M. D. Scadron

We comment on the results of a complete leading-twist next-to-leading order QCD analysis of the spacelike pion electromagnetic form factor at large-momentum transfer Q. For the asymptotic distribution amplitude, we have examined the…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Melic , B. Nizic , K. Passek

The pion electromagnetic form factor is calculated with a light-front quark model. The "plus" and "minus" component of the electromagnetic current are used to calculate the electromagnetic form factor in the Breit frame with two models for…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. P. B. C. de Melo

In this work, we employ a dispersion relation that allows to recover the electromagnetic form factor of the pion from its modulus along the unitarity cut. Unlike the standard dispersive approach, this method extends in a straightforward…

High Energy Physics - Phenomenology · Physics 2024-10-24 Pablo Sanchez-Puertas , Enrique Ruiz Arriola

We present results for the isovector axial, induced pseudoscalar, electric, and magnetic form factors of the nucleon. The calculations were done using $2+1+1$-flavor HISQ ensembles generated by the MILC collaboration with lattice spacings…

High Energy Physics - Lattice · Physics 2018-04-18 Yong-Chull Jang , Tanmoy Bhattacharya , Rajan Gupta , Huey-Wen Lin , Boram Yoon

We report on the lowest moment of parton distribution functions and generalized form factors for the pion at several values of the momentum transfer. Calculations are performed for N_f=2 flavors of O(a) improved Wilson fermions with pion…

High Energy Physics - Lattice · Physics 2013-12-02 G. Bali , S. Collins , B. Glässle , M. Göckeler , N. Javadi-Motaghi , J. Najjar , W. Söldner , A. Sternbeck

The current status of lattice-QCD numerical calculations by joint LHP, RBC, and UKQCD collaborations of nucleon isovector vector- and axialvector-current form factors using a 2+1-flavor dynamical domain-wall fermions lattice QCD ensemble…

High Energy Physics - Lattice · Physics 2023-11-13 Shigemi Ohta

The scalar form factors for the pions and kaons are calculated in SU(3) Chiral Perturbation Theory at order $p^6$, in the isospin limit $m_u=m_d=\hat{m}$. We find in general sizable corrections of $\mathcal{O}(p^6)$. We use our results to…

High Energy Physics - Phenomenology · Physics 2009-11-10 Johan Bijnens , Pierre Dhonte

The problem of determining the pion electromagnetic formfactor $F(q^2)$ in the space-like region from the value of its modulus in the time-like region is solved by the formfactor analyticity. If $F(q^2)$has no zeroes in the complex plane…

High Energy Physics - Phenomenology · Physics 2009-10-31 B. V. Geshkenbein

We consider finite volume effects on the electro-magnetic pion form factor near the chiral limit, in the so-called $\epsilon$ regime. The pseudoscalar-vector-pseudoscalar three-point function is calculated in the $\epsilon$ expansion of…

High Energy Physics - Lattice · Physics 2014-02-13 Hidenori Fukaya , Takashi Suzuki

We report on our calculation of the pion electromagnetic form factor with two-flavors of dynamical overlap quarks. Gauge configurations are generated using the Iwasaki gauge action on a 16^3 \times 32 lattice at the lattice spacing of…

High Energy Physics - Lattice · Physics 2009-04-14 JLQCD collaboration , T. Kaneko , H. Fukaya , S. Hashimoto , H. Matsufuru , J. Noaki , T. Onogi , N. Yamada

The pion electromagnetic form factor is investigated by using the dispersion relation with the superconvergence condition, which was proposed to synthesize the vector meson dominance model and QCD. The absorptive part is given as an…

High Energy Physics - Phenomenology · Physics 2007-05-23 Keiji Watanabe , Hirohisa Ishikawa , Masami Nakagawa

We present new N_f=2 data for the nucleon generalized form factors, varying volume, lattice spacing and pion mass, down to 150 MeV. We also give an update of our direct calculation of the nucleon sigma term for a range of pion mass values…

High Energy Physics - Lattice · Physics 2013-12-04 G. S. Bali , S. Collins , B. Gläßle , M. Göckeler , J. Najjar , R. Rödl , A. Schäfer , R. Schiel , W. Söldner , A. Sternbeck , P. Wein

We write down some relevant matrix elements for the scattering and decay processes of the pion by considering a quark-meson vertex function. The pion charge and transition form factors $F_\pi$, $F_{\pi\gamma}$, and $F_{\pi\gamma^*}$ are…

High Energy Physics - Phenomenology · Physics 2009-11-07 Chien-Wen Hwang
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