Strange mesons and kaon-to-pion transition form factors from holography

Abstract

We present a calculation of the K ℓ3 transition form factors using the AdS/QCD correspondence. We also solidify and extend our ability to calculate quantities in the flavor-broken versions of AdS/QCD. The normalization of the form factors is a crucial ingredient for extracting |Vus| from data, and the results obtained here agree well with results from chiral perturbation theory and lattice gauge theory. The slopes and curvature of the form factors agree well with the data, and with what results are available from other methods of calculation.

Decay constants of the pion and its excitations in holographic QCD

“…[17,26]: m q = 8.31 MeV and σ q = (213.7 MeV) 3 . They are chosen to fit the ground-state pion mass m π 0 = 139.6 MeV and leptonic decay constant f π 0 = 92.4 MeV -the latter will be discussed further ahead.…”

“…The bifundamental field X is decomposed into the classical part X 0 and a pseudoscalar fluctuation π in the following form [26]:…”

Nonlinear boundary dynamics and chiral symmetry in holographic QCD

“…The GOR relation is also satisfied in an SU(3) extension of the hard-wall model with an independent strange quark mass parameter [14]. Classical calculations in the hard-wall model have reproduced a variety of QCD observables with surprising accuracy, generally at the 10-15% level [5,6].…”

Strong couplings and form factors of charmed mesons in holographic QCD

“…In Ref. [35], Abidin and Carlson extended the model to N f = 3, to incorporate the strange-quark sector. In the present paper we further extend that model to N f = 4, with the aim of making predictions for charmed mesons.…”

“…The extension proposed in Ref. [35] incorporated the strange quark and was able to identify the appearance of scalar modes associated with flavor symmetry breaking. In the present work, by extending the model of Refs.…”