arXiv subjects
Publications and source records attributed to Y. Ünal.
We investigate the $C\!P$-odd electric dipole moments (EDMs) of spin-1/2 charm baryons considering $C\!P$-violating dimension-6 operators in the Standard Model effective field theory. In the framework of heavy-baryon chiral perturbation theory, we calculate the EDMs of single-charm baryons and present the estimates for beyond-the-standard model physics appearing at the TeV scale.
Triggered by experimental prospects to measure electromagnetic dipole moments of baryons containing a bottom quark, we calculate the CP-odd electric dipole moments (EDMs) of spin-1/2 single-bottom baryons. We consider CP-violating dimension-six operators in the Standard Model Effective Field Theory that involve bottom quarks, and apply heavy-baryon chiral perturbation theory to compute the EDMs of several baryons. We discuss the expected size of the EDMs for beyond-the-Standard Model physics appearing at the TeV scale.
We investigate the axial-vector nucleon-to-delta transition form factors in the framework of relativistic baryon chiral perturbation theory at the one-loop order using the complex-mass renormalization scheme. We determine the available six free parameters by fitting to an empirical parametrization of the form factors obtained from the BNL neutrino bubble chamber experiments. A unique feature of our calculation is the prediction of a non-vanishing form factor $C_3^A(Q^2)$. Moreover, our results show a surprising sensitivity to the coupling constant $\texttt{g}_1$ of the leading-order Lagrangian ${\cal L}^{(1)}_{πΔ}$.
We report on the calculation of the CP-violating form factor $F_3$ and the corresponding electric dipole moment for charmed baryons in the spin-1/2 sector generated by the QCD $θ$-term. We work in the framework of covariant baryon chiral perturbation theory within the extended-on-mass-shell renormalization scheme up to next-to-leading order in the chiral expansion.
We consider chiral perturbation theory with an explicit broad $σ$-meson and study its contribution to the scalar form factors of the pion and the nucleon. Our goal is to learn more about resonance saturation in the scalar sector.
Using baryon chiral perturbation theory including vector mesons, we analyse various continuum contributions to the isoscalar electromagnetic spectral functions of the nucleon induced by the leading order couplings.