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Related papers: QCD sum rules: form factors and wave functions

200 papers

Confronted with some surprising claims about experimentally measured or theoretically expected dependencies on the involved momentum transfer of various form factors of pseudoscalar mesons, we reassess the present status of these quantities…

High Energy Physics - Phenomenology · Physics 2012-11-01 Irina Balakireva , Wolfgang Lucha , Dmitri Melikhov

The $D^*D\pi$ form factor is evaluated at low and moderate $Q^2$ in a hadronic loop model, for off-shell $D$ mesons. The results contain arbitrary constants, which are fixed so as to match previous QCD sum rule calculations valid at higher…

High Energy Physics - Phenomenology · Physics 2015-06-25 F. O. Durães , F. S. Navarra , M. Nielsen , M. R. Robilotta

The electromagnetic form factor of the pion in the space-like region, and at finite temperature, $F_{\pi}(Q^{2},T)$, is obtained from a QCD Finite Energy Sum Rule. The form factor decreases with increasing T, and vanishes at some critical…

High Energy Physics - Phenomenology · Physics 2009-10-28 C. A. Dominguez , M. Loewe , J. S. Rozowsky

We present results of a calculation of the electromagnetic pion form factor within a framework of QCD Sum Rules with nonlocal condensates and using a perturbative spectral density which includes \mathcal{O}(\alpha_s) contributions.

High Energy Physics - Phenomenology · Physics 2014-11-18 A. P. Bakulev , A. V. Pimikov , N. G. Stefanis

The surprising results by the BarBar collaboration on the $\pi\gamma$ transition form factor require new thoughts about the high-$Q^2$ dependence of the form factors with virtual photons. We make use of the anomaly sum rule [J. Horejsi and…

High Energy Physics - Phenomenology · Physics 2012-04-03 Dmitri Melikhov , Berthold Stech

We review QCD sum rule applications to hadronic matrix elements of exclusive $B$ and $D$ decays. Results are presented for the form factors $f^+$ and $F_0$ of $B \rightarrow \pi$ and $D\rightarrow \pi$ transitions. The predictions are used…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Khodjamirian , R. Rückl

We calculate the form factors V, A_1, A_2 and A_0 appearing in the (D -> phi) transition in light cone QCD sum rule method. We compare our results on these form factors with the current experimental results and existing theoretical…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. M. Aliev , A. Ozpineci , M. Savci

The lightest meson, the pion, features two faces -- one is the elementary Goldstone boson of QCD and the other is the structured bound state of quarks and gluons. To accommodate both in a single light-front wave function in the valence…

High Energy Physics - Theory · Physics 2022-12-05 Yang Li , Pieter Maris , James P. Vary

We obtain the electromagnetic form factors of the nucleon, in the space-like region, using three-point function Finite Energy QCD Sum Rules. The QCD calculation is performed to leading order in perturbation theory in the chiral limit, and…

High Energy Physics - Phenomenology · Physics 2007-05-23 H. Castillo , C. A. Dominguez , M. Loewe

We study the pion form factor in a broad range of spacelike momentum transfers within the local-duality version of QCD sum rules. We make use of the recently calculated two-loop double spectral density of the $<AVA>$ correlator including…

High Energy Physics - Phenomenology · Physics 2008-11-26 Victor Braguta , Wolfgang Lucha , Dmitri Melikhov

The $D^*D\pi$ form factor is evaluated in a QCD sum rule calculation for both $D$ and $\pi$ off-shell mesons. We study the Borel sum rule for the three-point function of one pseudoscalar, one axial and one vector meson currents. We find…

High Energy Physics - Phenomenology · Physics 2009-11-07 F. S. Navarra , M. Nielsen , M. E. Bracco

Armed with the information on the form factor $\fdpi(0)$ inferred from recent CLEO measurements of SU(3)-breaking effects in charmed meson decays, we have studied the form factor $\fbpi$. In the heavy quark limit, $\fbpi(q^2)$ is related to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hai-Yang Cheng

The recent measurement from the CLEO experiment presents the $DD^*\pi$ coupling, $17.9\pm 0.3 \pm 1.9$. This value is much larger than any of QCD sum rule predictions available in literature. We report that, with a relevant treatment of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hungchong Kim

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 study two versions of lightcone sum rules to calculate the $\gamma^*\gamma\rightarrow\pi^0$ transition form factor (TFF) within QCD. While the standard version is based on fixed-order perturbation theory by means of a power-series…

High Energy Physics - Phenomenology · Physics 2022-02-16 Sergey Mikhailov , Alexandr Pimikov , N. G. Stefanis

Sum rules for the off-shell isovector form factor pi -> gamma gamma* are given in terms of the pion form factor and the gamma pi ->pi pi experimental data. Similarly the corresponding sum rules for the isoscalar form factor are given in…

High Energy Physics - Phenomenology · Physics 2007-05-23 Tran N. Truong

Using our present knowledge on effective hadronic theories, short-distance QCD information, the $1/N_C$ expansion, analyticity and unitarity, we derive an expression for the pion form factor, in terms of $m_\pi, m_K, M_\rho$ and $f_\pi$.…

High Energy Physics - Phenomenology · Physics 2011-05-05 F. Guerrero , A. Pich

We revisit the $\rho$-meson longitudinal leading-twist distribution amplitude (DA) $\phi_{2;\rho}^\|$ by using the QCD sum rules approach within the background field theory. To improve the accuracy of the sum rules for its moments…

High Energy Physics - Phenomenology · Physics 2016-10-05 Hai-Bing Fu , Xing-Gang Wu , Wei Cheng , Tao Zhong

We discuss applications of QCD sum rules on the light-cone to the form factors of the exclusive transitions $B \rightarrow \pi$ and $D\rightarrow \pi$, and to the $B^*B \pi$ and $D^*D \pi$ coupling constants. In the light of our results we…

High Energy Physics - Phenomenology · Physics 2016-09-01 A. Khodjamirian , R. Rückl

We calculate the $D^*D\pi$ and $B^*B\pi$ couplings using QCD sum rules on the light-cone. In this approach, the large-distance dynamics is incorporated in a set of pion wave functions. We take into account two-particle and three-particle…

High Energy Physics - Phenomenology · Physics 2014-11-17 V. M. Belyaev , V. M. Braun , A. Khodjamirian , R. Rückl