J. Bijnens, G. Colangelo, G. Ecker, M. E. Sainio
We evaluate analytically the elastic scattering amplitude to two loops in chiral perturbation theory and give numerical values for the two S--wave scattering lengths and for the phase shift...
Vector Meson Masses in Chiral Perturbation Theory (2007)
Bijnens Gosdzinsky, J. Bijnens, P. Gosdzinsky, P. Talavera
We discuss the vector meson masses within the context of Chiral Perturbation Theory performing an expansion in terms of the momenta, quark masses and 1=Nc . We extend the previous analysis to include...
Chiral--Loop And Vector--Meson Contributions To (2007)
Flfl Decays, J. Bijnens, A. Bramon, P. Talavera
The process j ! ß 0 ß 0 flfl is discussed in Chiral Perturbation Theory (ChPT). Special attention is devoted to one-loop corrections, j-j 0 mixing effects and vector-meson dominance of ChPT...
Pion-Pion Scattering at Low Energy (2007)
J. Bijnens, G. Colangelo, G. Ecker, J. Gasser, M. E. Sainio
We present technical details of the evaluation of the elastic ßß scattering amplitude to two loops in chiral perturbation theory. In particular, we elaborate on the renormalization procedure at the...
Vector Meson Masses in Chiral Perturbation Theory (2007)
Bijnens Gosdzinsky And, J. Bijnens, P. Gosdzinsky, P. Talavera
We discuss the vector meson masses within the context of Chiral Perturbation Theory performing an expansion in terms of the momenta, quark masses and 1=Nc . We extend the previous analysis to include...
Chiral Corrections to Vector Meson Decay Constants (2007)
Bijnens Gosdzinsky And, Lu Tp, J. Bijnens, P. Gosdzinsky, P. Talavera
We calculate the leading quark mass corrections of order m q log(m q ), m q and m 3=2 q to the vector meson decay constants within Heavy Vector Meson Chiral Perturbation Theory. We discuss the issue...
Electromagnetic Contributions to Vector Meson Masses and Mixings (2007)
We use the 1=N c method to estimate electromagnetic contributions to vector meson masses and mixings. We identify several new sources of ae \Gamma ! mixing coming from short-distance effects. We...
Chiral Corrections to Vector Meson Decay Constants (2007)
Bijnens Gosdzinsky, J. Bijnens, P. Gosdzinsky, P. Talavera
We calculate the leading quark mass corrections of order m q log(m q ), m q and m 3=2 q to the vector meson decay constants within Heavy Vector Meson Chiral Perturbation Theory. We discuss the issue...
We review the status of the hadronic light-by-light contribution to the muon anomalous magnetic moment and critically compare recent calculations. We also study in detail which momentum regions the...
$K_{l4}$ at two-loops and CHPT predictions for $\pi\pi$-scattering (2006)
Amoros, G., Bijnens, J., Talavera, P.
We present the results from our two-loop calculations of masses, decay-constants, vacuum-expectation-values and the $K_{\ell4}$ form-factors in three-flavour Chiral Perturbation Theory (CHPT). We use...
Pion and Kaon Electromagnetic Form Factors (2002)
We study the electromagnetic form factor of the pion and kaons at low-energies with the use of Chiral Perturbation Theory. The analysis is performed within the three avour framework and at...
The anomalous chiral Lagrangian of order $p^6$ (2001)
Bijnens, J., Girlanda, L., Talavera, P.
We construct the effective chiral Lagrangian for chiral perturbation theory in the mesonic odd-intrinsic-parity sector at order $p^6$. The Lagrangian contains 24 in principle measurable terms and no...
The exact form of the form-factor associated with a meson-photon-photon vertex is not known. Different suggestions exist, based on constraints from QCD and on recent experiments. Four different...
QCD Signatures of Narrow Graviton Resonances in Hadron Colliders (2001)
Bijnens, J, Eerola, Paule Anna Mari, Maul, M, Mansson, A, Sjöstrand, Torbjörn
We show that the characteristic p_\perp spectrum yields valuable information for the test of models for the production of narrow graviton resonances in the TeV range at LHC. Furthermore, it is...
QCD Signatures of Narrow Graviton Resonances in Hadron Colliders (2001)
Bijnens, J., Eerola, P., Maul, M., Mansson, A., Sjostrand, T.
We show that the characteristic p_\perp spectrum yields valuable information for the test of models for the production of narrow graviton resonances in the TeV range at LHC. Furthermore, it is...
QCD Isospin Breaking in Meson Masses, Decay Constants and Quark Mass Ratios (2001)
Amoros, G., Bijnens, J., Talavera, P.
The procedure to calculate masses and matrix-elements in the presence of mixing of the basis states is explained in detail. We then apply this procedure to the two-loop calculation in Chiral...
QCD isospin breaking in meson masses, decay constants and quark mass ratios (2001)
Amoros, G., Bijnens, J., Talavera, P.
The procedure to calculate masses and matrix-elements in the presence of mixing of the basis states is explained in detail. We then apply this procedure to the two-loop calculation in Chiral...
QCD isospin breaking in meson masses, decay constants and quark mass ratios (2001)
Amoros, G., Bijnens, J., Talavera, P.
The procedure to calculate masses and matrix-elements in the presence of mixing of the basis states is explained in detail. We then apply this procedure to the two-loop calculation in Chiral...
$K_{\ell 4}$ Form-Factors and $\pi$-$\pi$ Scattering (2000)
Amoros, G., Bijnens, J., Talavera, P.
The $F$ and $G$ form-factors of $K_{\ell4}$ and the quark condensates are calculated to ${\cal O}(p^6)$ in Chiral Perturbation Theory (CHPT). Full formulas are presented as much as possible. A full...
$K_{l4}$ at two-loops and CHPT predictions for $\pi\pi$-scattering (2000)
Amoros, G., Bijnens, J., Talavera, P.
We present the results from our two-loop calculations of masses, decay-constants, vacuum-expectation-values and the $K_{\ell4}$ form-factors in three-flavour Chiral Perturbation Theory (CHPT). We use...
$K_{l4}$ at two-loops and CHPT predictions for $\pi\pi$-scattering (2000)
Amoros, G., Bijnens, J., Talavera, P.
We present the results from our two-loop calculations of masses, decay-constants, vacuum-expectation-values and the $K_{\ell4}$ form-factors in three-flavour Chiral Perturbation Theory (CHPT). We use...
Low Energy Constants from Kl4 Form-Factors (1999)
Amorós, G., Bijnens, J., Talavera, P.
We have calculated the form-factors F and G in K ---> pi pi e nu decays (Kl4) to two-loop order in Chiral Perturbation Theory (ChPT). Combining this together with earlier two-loop calculations an...
Renormalization of chiral perturbation theory to order p^6 (1999)
Bijnens, J., Colangelo, G., Ecker, G.
The renormalization of chiral perturbation theory is carried out to next-to-next-to-leading order in the meson sector. We calculate the divergent part of the generating functional of Green functions...
Bijnens, J., Colangelo, G., Ecker, G.
We determine the full structure of the leading (double-pole) divergences of O(p^6) in the meson sector of chiral perturbation theory. The field theoretic basis for this calculation is described. We...
The Vector and Scalar Form Factors of the Pion to Two Loops (1998)
Bijnens, J., Colangelo, G., Talavera, P.
We calculate the vector and scalar form factors of the pion to two loops in Chiral Perturbation Theory. We estimate the unknown O(p^6) constants using resonance exchange. We make a careful comparison...
The Vector and Scalar Form Factors of the Pion to Two Loops (1998)
J. Bijnens, G. Colangelo, P. Talavera
: We calculate the vector and scalar form factors of the pion to two loops in Chiral Perturbation Theory. We estimate the unknown O(p 6 ) constants using resonance exchange. We make a careful...
Lu Tp, J. Bijnens, G. Colangelo, G. Ecker
We determine the full structure of the leading (double-pole) divergences of O(p 6 ) in the meson sector of chiral perturbation theory. The field theoretic basis for this calculation is described. We...
Report of the Working Group on Goldstone Boson Production and Decay (1997)
Bijnens, J., Colangelo, G., D'Ambrosio, G., Gabbiani, F., Isidori, G., Kambor, J., ...
This is the summary of the working group on Goldstone Boson Production and Decay of the Chiral Dynamics Workshop in Mainz, September 1-5, 1997. For the production aspects we discuss $\pi^0$ and...
Matching the Heavy Vector Meson Theory (1997)
Bijnens, J., Gosdzinsky, P., Talavera, P.
We show how to obtain a ``heavy'' meson effective lagrangian for the case where the number of heavy particles is not conserved. We apply the method in a simple example at tree level and perform then...
Pion-pion scattering at low energy (1997)
Bijnens, J., Colangelo, G., Ecker, G., Gasser, J., Sainio, M. E.
We present technical details of the evaluation of the elastic pi-pi scattering amplitude to two loops in chiral perturbation theory. In particular, we elaborate on the renormalization procedure at...
Chiral Perturbation Theory and Threshold Corrections (1997)
I give a short overview of Chiral Perturbation Theory, its underlying assumptions and underpinnings. A few examples are included.
Vector Meson Masses in Chiral Perturbation Theory (1997)
Bijnens, J., Gosdzinsky, P., Talavera, P.
We discuss the vector meson masses within the context of Chiral Perturbation Theory performing an expansion in terms of the momenta, quark masses and 1/Nc. We extend the previous analysis to include...
Chiral-loop and vector-meson contributions to eta -> pi pi gamma gamma decays (1997)
Ametller, Ll., Bijnens, J., Bramon, A., Talavera, P.
The process eta -> pi0 pi0 gamma gamma is discussed in Chiral Perturbation Theory (ChPT) extending two recent analyses. Special attention is devoted to one-loop corrections, eta-eta' mixing effects...
Goldstone Boson Production and Decay (1997)
Johan Bijnens, Chiral Perturbation, J. Bijnens
. Various topics in and around Goldstone Boson Production and Decay in CHPT are discussed, in particular I describe some of the progress in p 6 Chiral Perturbation Theory Calculations, the progress...
Report of the Working Group on Goldstone Boson Production and Decay (1997)
J. Bijnens, G. Colangelo, G. D'Ambrosio, F. Gabbiani, G. Isidori, J. Kambor, ...
. This is the summary of the working group on Goldstone Boson Production and Decay of the Chiral Dynamics Workshop in Mainz, September 1-5, 1997. For the production aspects we discuss ß 0 and j...
$\pi \to l\nu \gamma$ Form Factors at Two-loop (1996)
Within Chiral Perturbation Theory (CHPT) we compute the form factors A, V and $\gamma = A/V$ in the $\pi \to \nu l \gamma$ decay to $O(p^6)$. A and $\gamma$ obtain corrections of order 25%.
Electromagnetic Contributions to Vector Meson Masses and Mixings (1996)
We use the 1/N_c method to estimate electromagnetic contributions to vector meson masses and mixings. We identify several new sources of rho-omega mixing coming from short-distance effects. We...
Chiral Perturbation Theory for DA$\Phi$NE Physics (1996)
This talk is an overview of Chiral Perturbation Theory for Kaon physics as far as not covered by other speakers. It includes a short introduction to the strengths and weaknesses of Chiral...
The Standard Model at Low Energies (1996)
These are short proceedings of the workshop on ``The Standard Model at Low Energies'' held at ECT* in Trento, Italy, from April 29 to May 10, 1996. The workshop concentrated on Chiral Perturbation...
Workshop on The Standard Model at Low Energies (1996)
BOOKLET These are short proceedings of the workshop on "The Standard Model at Low Energies" held at ECT* in Trento, Italy, from April 29 to May 10, 1996. The workshop concentrated on Chiral...
π → lνγ Form Factors at Two-loop (1996)
J. Bijnens, P. Talavera, Nordita Blegdamsvej
Within Chiral Perturbation Theory (CHPT) we compute the form factors A, V and γ = A/V in the π → lνγ decay to O(p^6). A and γ obtain corrections...
$\gamma \gamma \to \pi \pi \pi$ to One Loop in Chiral Perturbation Theory (1995)
Talavera, P., Ametller, Ll., Bijnens, J., Bramon, A., Cornet, F.
The $\gamma\gamma \to \pi^0 \pi^0 \pi^0$ and $\gamma\gamma \to \pi^+ \pi^- \pi^0$ amplitudes are discussed in the general context of Chiral Perturbation Theory (ChPT) to $O(p^6)$. Chiral loops are...
Elastic $\pi\pi$ scattering to two loops (1995)
Bijnens, J., Colangelo, G., Ecker, G., Gasser, J., Sainio, M. E.
We evaluate analytically the elastic $\pi\pi$ scattering amplitude to two loops in chiral perturbation theory and give numerical values for the two $S$--wave scattering lengths and for the phase...
Renormalization of Chiral Perturbation Theory to Order (1995)
Bijnens Colangelo And, J. Bijnens, G. Colangelo, G. Ecker, Irchel Switzerland
The renormalization of chiral perturbation theory is carried out to next-tonext -to-leading order in the meson sector. We calculate the divergent part of the generating functional of Green functions...
Elastic Pi Pi Scattering to Two Loops (1995)
J. Bijnens, G. Colangelo, G. Ecker, J. Gaser, M. E. Sainio
We evaluate analytically the elastic ßß scattering amplitude to two loops in chiral perturbation theory and give numerical values for the two S--wave scattering lengths and for the phase shift...
2 And 3-point functions in the ENJL-model (1994)
We discuss the extended Nambu-Jona-Lasinio model as a low energy expansion, all two-point functions and an example of a three-point function to all orders in momenta and quark masses. The model is...
Semileptonic Kaon Decays (1994)
Bijnens, J., Colangelo, G., Ecker, G., Gasser, J.
We present the matrix elements for the semileptonic kaon decays $K_{l2\gamma}$ , $K_{l2l^+l^-}$, $K_{l2l'^+l'^-}$,$K_{l3}$, $K_{l3\gamma}$ and $K_{l4}$ at next-to-leading order, and $K_{e5}$ at...
Chiral Perturbation Theory (1994)
Bijnens, J., Ecker, G., Gasser, J.
An introduction to Chiral Perturbation Theory is given including a discussion of power counting, the Wess-Zumino term, the values of the coupling constants and the inclusion of the effects of other...
2 and 3-point functions in the ENJL-model (1994)
We discuss the extended Nambu-Jona-Lasinio model as a low energy expansion, all two-point functions and an example of a three-point function to all orders in momenta and quark masses. The model is...
$K_{l4}$ - Decays Beyond One Loop (1994)
Bijnens, J., Colangelo, G., Gasser, J.
The matrix elements for $K\rightarrow \pi \pi \l \nu$ decays are described by four form factors $F,G,H$ and $R$. We complete previous calculations by evaluating $R$ at next-to-leading order in the...
Semileptonic $\pi$ and $K$ Decays and the Chiral Anomaly at One-loop (1993)
Ametller, Ll., Bijnens, J., Bramon, A., Cornet, F.
We calculate the $O(p^6)$ corrections to the anomalous form factors appearing in $\pi^+$, $K^+ \to e^+ \nu \gamma,\ \mu^+\nu\gamma$ and $K_{l4}$ decays in Chiral Perturbation Theory. The relevant...
Violations of Dashen's Theorem (1993)
The electromagnetic contribution to the $K^+ - K^0$ mass difference is calculated in the $1/N_c$ approach including the $SU(3)$ breaking contributions due to a non-zero strange quark mass. The...
Radiative Semileptonic Kaon Decays (1992)
Bijnens, J., Ecker, G., Gasser, J.
We evaluate the matrix elements for the radiative kaon decays $K^+ \to l^+\nu_l\gamma$, $l^+ \nu_l l'^+ l'^-$ and $K \to \pi l \nu_l\gamma$ \ ($l,\ l' = e,\mu$) to next-to-leading order in chiral...
Radiative semileptonic kaon decays (1992)
Bijnens, J, Ecker, G, Gasser, J
We evaluate the matrix elements for the radiative kaon decays $K^+ \to l^+\nu_l\gamma$, $l^+ \nu_l l'^+ l'^-$ and $K \to \pi l \nu_l\gamma$ \ ($l,\ l' = e,\mu$) to next-to-leading order in chiral...
Semileptonic Kaon Decays in Chiral Perturbation Theory (1992)
Bijnens, J., Ecker, G., Gasser, J.
We present the matrix elements for the semileptonic kaon decays $K_{l2\gamma}$, $K_{l2l^+l^-}$, $K_{l2l'^+l'^-}$, $K_{l3}$, $K_{l3\gamma}$ and $K_{l4}$ at next-to-leading order in chiral perturbation...
Nambu - Jona-Lasinio-like models and the low-energy effective action of QCD (1992)
Bijnens, J, Bruno, C, De Rafael, E
We present a derivation of the low energy effective action of an extended Nambu Jona-Lasinio (ENJL) model to $O(p^4)$ in the chiral counting. Two alternative scenarios are considered on how the ENJL...
The chiral anomaly in non-leptonic weak interactions (1992)
Bijnens, J, Ecker, G, Pich, Antonio
The interplay between the chiral anomaly and the non-leptonic weak Hamiltonian is studied. The structure of the corresponding effective Lagrangian of odd intrinsic parity is established. It is shown...
The Chiral Anomaly in Non-Leptonic Weak Interactions (1992)
Bijnens, J., Ecker, G., Pich, A.
The interplay between the chiral anomaly and the non-leptonic weak Hamiltonian is studied. The structure of the corresponding effective Lagrangian of odd intrinsic parity is established. It is shown...
Two--Body Decays of $B_s$ Mesons (1992)
We have calculated the decay rates of the $B_s$ meson in a number of exclusive two--body decay channels using the Bauer--Stech--Wirbel model for current matrix elements. The influence of the free...