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Related papers: Chiral sum rules to second order in quark mass

200 papers

The strange quark mass is calculated from QCD sum rules for the divergence of the vector as well as axial-vector current in the next-next-to-leading logarithmic approximation. The determination for the divergence of the axial-vector current…

High Energy Physics - Phenomenology · Physics 2008-11-26 Matthias Jamin , Manfred M"unz

We calculate the contributions arising at order $\alpha_s$ in the QCD sum rule for the spin-symmetry violating universal function $\chi_3(v\cdot v')$, which appears at order $1/m_Q$ in the heavy quark expansion of meson form factors. In…

High Energy Physics - Phenomenology · Physics 2009-10-22 M. Neubert , Z. Ligeti , Y. Nir

Chiral perturbation theory in the two--flavour sector allows one to analyse Green functions in QCD in the limit where the strange quark mass is considered to be large in comparison to the external momenta and to the light quark masses m_u…

High Energy Physics - Phenomenology · Physics 2015-05-14 Juerg Gasser , Christoph Haefeli , Mikhail A. Ivanov , Martin Schmid

Sum rules for the low-energy constants of the chiral SU(3) Lagrangian with charmed baryons of spin J^P=1/2^+ and J^P=3/2^+ baryons are derived from large-N_c QCD. We consider the large-$N_c$ operator expansion at subleading orders for…

High Energy Physics - Phenomenology · Physics 2019-03-26 Yonggoo Heo , Matthias F. M. Lutz

We construct the next-to-leading order chiral lagrangian for scalar and pseudo-scalar densities defined using the gradient flow. We calculate the chiral condensate and the pion decay constant to this order from operators at positive flow…

High Energy Physics - Lattice · Physics 2014-05-21 Oliver Bar , Maarten Golterman

We construct the quark-antiquark chiral odd distribution amplitudes including twist-four mass contributions for tensor mesons. We also give quark-antiquark-gluon distribution amplitudes, where we calculate the input parameters with QCD sum…

High Energy Physics - Phenomenology · Physics 2018-07-11 Maximilian Emmerich , Matthias Strohmaier , Andreas Schäfer

In this article, we assume that the two quarks have unequal masses and calculate the next-to-leading order contributions to the spectral densities of the mesonic two-point correlation functions of the vector, axialvector, scalar and…

High Energy Physics - Phenomenology · Physics 2013-11-08 Zhi-Gang Wang

In this work, the mass of the strange quark is calculated from QCD sum rules for the divergence of the strangeness-changing vector current. The phenomenological scalar spectral function which enters the sum rule is determined from our…

High Energy Physics - Phenomenology · Physics 2008-11-26 Matthias Jamin , Jose Antonio Oller , Antonio Pich

QCD finite energy sum rules, together with the latest updated ALEPH data on hadronic decays of the tau-lepton are used in order to determine the vacuum condensates of dimension $d=2$ and $d=4$. These data are also used to check the validity…

High Energy Physics - Phenomenology · Physics 2015-06-23 C. A. Dominguez , L. A. Hernandez , K. Schilcher , H. Spiesberger

The concept of QCD sum rules is extended to bound states composed of particles with finite mass such as scalar quarks or strange quarks. It turns out that mass corrections become important in this context. The number of relevant corrections…

High Energy Physics - Phenomenology · Physics 2015-06-25 M. Meyer-Hermann , A. Schäfer , W. Greiner

A combination of finite energy sum rule techniques and Chiral Perturbation Theory (ChPT) is used in order to exploit recent ALEPH data on the non-strange tau vector (V) and axial-vector (A) spectral functions with respect to an experimental…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Davier , L. Girlanda , A. Hoecker , J. Stern

A chiral extrapolation of the light vector meson masses in the up, down and strange quark masses of QCD is presented. We apply an effective chiral Lagrangian based on the hadrogenesis conjecture to QCD lattice ensembles of PACS-CS,…

High Energy Physics - Lattice · Physics 2019-06-26 Xiao-Yu Guo , Matthias F. M. Lutz

We study the Dirac decomposition of the gauge invariant quark propagator, whose imaginary part describes the hadronization of a quark as this interacts with the vacuum, and relate each of its coefficients to a specific sum rule for the…

High Energy Physics - Phenomenology · Physics 2023-12-15 Alberto Accardi , Caroline S. R. Costa , Andrea Signori

A representation of the two-loop contribution to the pion decay constant in $SU(3)$ chiral perturbation theory is presented. The result is analytic upto the contribution of the three (different) mass sunset integrals, for which an expansion…

High Energy Physics - Phenomenology · Physics 2017-10-06 B. Ananthanarayan , Johan Bijnens , Shayan Ghosh

We report on a novel scheme based on the chiral Lagrangian. It is used to analyze pion-nucleon scattering, pion photoproduction, and nucleon Compton scattering. Subthreshold partial-wave amplitudes are calculated in chiral perturbation…

High Energy Physics - Phenomenology · Physics 2015-05-20 A. M. Gasparyan , M. F. M. Lutz

The next to leading order chiral corrections to the $SU(2)\times SU(2)$ Gell-Mann-Oakes-Renner (GMOR) relation are obtained using the pseudoscalar correlator to five-loop order in perturbative QCD, together with new finite energy sum rules…

High Energy Physics - Phenomenology · Physics 2012-01-25 J. Bordes , C. A. Dominguez , P. Moodley , J. Peñarrocha , K. Schilcher

A new determination of the strange-quark mass is discussed, based on the two-point function involving the axial-vector current divergences. This Green function is known in perturbative QCD up to order O(alpha_s^3), and up to dimension-six…

High Energy Physics - Phenomenology · Physics 2009-10-31 C. A. Dominguez , L. Pirovano , K. Schilcher

Using quenched and unquenched chiral perturbation theory we compute vector and axial current two-point functions at finite volume and fixed gauge field topology, in the so-called \epsilon-regime of QCD. A comparison of these results with…

High Energy Physics - Lattice · Physics 2009-11-10 P. H. Damgaard , P. Hernandez , K. Jansen , M. Laine , L. Lellouch

We derive two sum rules by studying the low energy Compton scattering on a target of arbitrary (nonzero) spin j. In the first sum rule, we consider the possibility that the intermediate state in the scattering can have spin |j \pm 1| and…

High Energy Physics - Theory · Physics 2012-10-11 Hovhannes R. Grigoryan , Massimo Porrati

We derive new QCD sum rules for the axial coupling constants by considering two-point correlation functions of the axial-vector currents in a one nucleon state. The QCD sum rules tell us that the axial coupling constants are expressed by…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. Nishikawa , S. Saito , Y. Kondo