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Related papers: A glimpse into pion gravitational form factor

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We present the first calculation of the pion electromagnetic form factor at physical light quark masses. This form factor parameterises the deviations from the behaviour of a point-like particle when a photon hits the pion. These deviations…

High Energy Physics - Lattice · Physics 2017-10-23 Jonna Koponen , Francis Bursa , Christine T. H. Davies , Rachel J. Dowdall , G. Peter Lepage

We consider the pion structure in the region of low and moderately high momentum transfers: at low $Q^2$, the pion is treated as a composite system of constituent quarks; at moderately high momentum transfers, $Q^2=10\div25\;GeV^2$, the…

High Energy Physics - Phenomenology · Physics 2009-10-28 V. Anisovich , D. Melikhov , V. Nikonov

The pion electromagnetic form factor at spacelike momentum transfer is calculated in relativistic impulse approximation using the Covariant Spectator Theory. The same dressed quark mass function and the equation for the pion bound-state…

High Energy Physics - Phenomenology · Physics 2014-01-09 Elmar P. Biernat , Franz Gross , M. T. Peña , Alfred Stadler

We present preliminary results from the first calculation of the pion electromagnetic form factor at physical light quark masses. This form factor parameterises the deviations from the behaviour of a point-like particle when a photon hits…

High Energy Physics - Lattice · Physics 2013-11-15 Jonna Koponen , Francis Bursa , Christine Davies , Gordon Donald , Rachel Dowdall

The behaviour of the pion transition form factor for the process $\gamma^\star\gamma \to \pi^0$ and $\gamma^\star\gamma^\star\to \pi^0$ at space-like values of photon momenta is estimated within the nonlocal covariant quark-meson model. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. E. Dorokhov

We present a calculation of the electromagnetic form factor of the pion in $N_f=2+1$ flavor lattice QCD. Calculations are made on the PACS-CS gauge field configurations generated using Iwasaki gauge action and Wilson-clover quark action on…

High Energy Physics - Lattice · Physics 2011-05-09 Oanh Hoang Nguyen , Ken-Ichi Ishikawa , Akira Ukawa , Naoya Ukita

We calculate the electromagnetic form factor of the pion in quenched lattice QCD. The non-perturbatively improved Sheikoleslami-Wohlert lattice action is used together with the consistently O(a) improved current. We calculate the pion form…

High Energy Physics - Lattice · Physics 2009-11-10 J. van der Heide , J. H. Koch , E. Laermann

A continuum approach to quark-antiquark bound-states is used to determine the electromagnetic form factors of pion-like mesons with masses $m_{0^-}/{\rm GeV}=0.14$, $0.47$, $0.69$, $0.83$ on a spacelike domain that extends to $Q^2 \lesssim…

Nuclear Theory · Physics 2018-12-05 Muyang Chen , Minghui Ding , Lei Chang , Craig D. Roberts

The electromagnetic form factor of the pion is calculated within the use of functional formalism. We develop integral representation for the minimal set of Standard Model Green's functions and derive the dispersion relation for the form…

High Energy Physics - Phenomenology · Physics 2022-09-30 Vladimir Sauli

We employ a dispersion relation that allows to recover the phase of the electromagnetic form factor of the pion from its absolute value above threshold. Compared to alternative approaches building on the phase, this approach builds on…

High Energy Physics - Phenomenology · Physics 2024-07-29 Enrique Ruiz Arriola , Pablo Sanchez-Puertas

We present a quantitative analysis of the electromagnetic pion form factor in the light-cone sum rule approach, including radiative corrections and higher-twist effects. The comparison to the existing data favors the asymptotic profile of…

High Energy Physics - Phenomenology · Physics 2011-05-05 V. M. Braun , A. Khodjamirian , M. Maul

We present an investigation of the electromagnetic pion form factor, $F_\pi(Q^2)$, at small values of the four-momentum transfer $Q^2$ ($\lesssim 0.25$ GeV$^2$), based on the gauge configurations generated by European Twisted Mass…

Results of the Spectral Quark Model for the gravitational, electromagnetic, and transition form factors of the pion are discussed. In this model both the parton distribution amplitude and the parton distribution function are flat, in…

High Energy Physics - Phenomenology · Physics 2009-10-10 Wojciech Broniowski , Enrique Ruiz Arriola

We present a formula that allows one to calculate the pion form factor in the timelike region 2mpi <= sqrt{s} <= 4mpi in lattice QCD. The form factor quantifies the contribution of two-pion states to the vacuum polarization. It must be…

High Energy Physics - Lattice · Physics 2012-04-04 Harvey B. Meyer

The presently experimentally interesting form factor for the anomalous process gamma -> pi^+ pi^0 pi^- is calculated as the quark "box"-amplitude where the intermediate fermion loop is the one of constituent quarks with the pseudoscalar…

High Energy Physics - Phenomenology · Physics 2009-10-31 Bojan Bistrovic , Dubravko Klabucar

We discuss the nonleading, ``soft" contribution to the pion form factor at intermediate momentum transfer within operator product expansion approach. We argue, that the corresponding contribution can temporarily {\bf simulate} the leading…

High Energy Physics - Phenomenology · Physics 2009-09-25 A. Zhitnitsky

Based on the field-theory-inspired approach, a new expression for the pion form factor F_pi is proposed. It takes into account the pseudoscalar meson loops $\pi^+\pi^-$ and $K\bar K$ and the mixing of $\rho(770)$ with heavier $\rho(1450)$…

High Energy Physics - Phenomenology · Physics 2015-06-11 N. N. Achasov , A. A. Kozhevnikov

Holographic QCD provides a unique framework in which to compute QCD observables. In this talk we summarize recent numerical work on computing the pion electromagnetic form factor using an AdS/QCD action that includes both spontaneous and…

High Energy Physics - Phenomenology · Physics 2017-08-23 Herry J. Kwee , Richard F. Lebed

We present a lattice calculation of the vector form factor of the pion for two flavours of non-perturbatively O(a) improved Wilson fermions. For the measurements we utilise the CLS ensembles which include various lattice spacings and pion…

High Energy Physics - Lattice · Physics 2011-09-02 Bastian B. Brandt , Andreas Juttner , Hartmut Wittig

The pion distribution amplitude (DA) can be related to the fundamental QCD Green's functions as a function of the quark self-energy and the quark-pion vertex, which in turn are associated with the pion wave function through the…

High Energy Physics - Phenomenology · Physics 2015-06-23 E. G. S. Luna , A. A. Natale