Related papers: The Decuplet Revisited in $\chi$PT
The branching ratios of the measured decay $K_L\to\pi^+\pi^-e^+e^-$ and of the still unmeasured decay $K^+\to\pi^+\pi^0e^+e^-$ are calculated to next-to-leading order in Chiral Perturbation Theory (CHPT). Recent experimental results are…
The contributions of the lightest tensor-meson resonances to the low-energy coupling constants of second order chiral perturbation theory with two flavours are evaluated and compared with the available phenomenological information as well…
We re-evaluate the electromagnetic corrections to eta --> 3 pi decays at next-to-leading order in the chiral expansion, arguing that effects of order e^2(m_d-m_u) disregarded so far are not negligible compared to other contributions of…
We present the results of a search for relations between observables that are independent of the Chiral Perturbation Theory (ChPT) Next-to-Next-to-Leading Order (NNLO) Low-Energy Constants (LECs). We have found some relations between…
We present in this talk recent results of the magnetic moments of the baryon antidecuplet within the framework of the chiral quark-soliton model in the chiral limit. The dynamic parameters of the model are fixed by using the experimental…
I briefly review the current status of chiral perturbation theory in the meson sector. Emphasis is given on the quest for higher precision. I discuss two examples: one where it is difficult to make a good prediction (K_L -> pi^0 gamma…
Heavy baryon chiral perturbation theory including spin 3/2 delta resonances as effective degrees of freedom is reviewed. The theory admits a systematic expansion in the small scale $\epsilon$, where $\epsilon$ collectively denotes soft…
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 then use an extension of this result to…
We present the first direct evaluation of DI = 3/2 K -> pi pi matrix elements with the aim of determining all the low-energy constants at NLO in the chiral expansion. Our numerical investigation demonstrates that it is indeed possible to…
Dark pions are promising dark matter candidates, yet most analyses rely on leading-order (LO) chiral perturbation theory (ChPT). Motivated by the fact that, even for QCD pi-pi scattering, LO ChPT near threshold underestimates the isoscalar…
We discuss the matching between long-distance and short-distance at next-to-leading in $1/N_c$ and show how the scheme-dependence from the two-loop renormalization group running can be treated. We then use this method to study the three…
We study the |Delta I|=3/2 amplitudes of hyperon non-leptonic decays of the form B->B'+pi in the context of chiral perturbation theory. The lowest-order predictions are determined in terms of only one unknown parameter and are consistent…
Nucleon electric dipole moments originating from strong CP-violation are being calculated by several groups using lattice QCD. We revisit the finite volume corrections to the CP-odd nucleon matrix elements of the electromagnetic current,…
The $\eta \to \pi^+ \pi^- \pi^0 \gamma$ decay is discussed in the general context of Chiral Perturbation Theory (ChPT), assuming that the low--energy constants (counter--terms) are saturated by vector-meson resonances. The $\eta \to \pi^+…
The dipole moments of the leptons and quarks are matrices in flavor space, which can potentially reveal as much about the flavor structure of the theory as do the mass matrices. The off-diagonal elements of the dipole matrices lead to…
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…
We study the complete one-loop contributions to the chromagnetic dipole moment $\Delta\kappa$ of the top quark in the Standard Model, two Higgs doublet models, topcolor assited technicolor models (TC2), 331 models and extended models with a…
We consider few problems which are related to the deuteron and have simple analytical solution. Relation is found between the deuteron electric quadrupole moment and the $np$-scattering amplitude. The degree of circular polarization of…
The electromagnetic corrections to the masses of the pseudoscalar mesons $\pi$ and $K$ are considered. We calculate in chiral perturbation theory the contributions which arise from resonances within a photon loop at order $O(e^2 m_q)$.…
Heavy baryon chiral perturbation theory for pentaquarks is applied beyond leading order. The mass splitting in the pentaquark anti-decuplet is calculated up to NNLO. An expansion in the coupling of pentaquarks to non-exotic baryons…