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B. R. Holstein

Publications and source records attributed to B. R. Holstein.

22 records · Page 2Linked to original sources
arXiv1998

Non-leptonic hyperon decays in chiral perturbation theory

The non-leptonic hyperon decays are analyzed up to one-loop order including all counterterms in the framework of heavy baryon chiral perturbation theory. We use the exchange of the spin-3/2 decuplet resonances as an indication of which low-energy constants contribute significantly to these investigated processes . We choose four independent decay amplitudes that are not related by isospin relations in order to perform a fit for the pertinent low-energy constants and find a satisfactory fit both for s- and p-waves. The chiral corrections to the lowest order forms for the s-waves are moderate whereas there are significant modifications of the p-wave amplitudes.

hep-ph↗
arXiv1996

Virtual Compton Scattering and Generalized Polarizabilities of the Nucleon in Heavy Baryon Chiral Perturbation Theory

The spin-independent part of the virtual Compton scattering (VCS) amplitude from the nucleon is calculated within the framework of heavy baryon chiral perturbation theory (HBChPT). The calculation is performed to third order in external momenta according to chiral power counting. The relation of the tree-level amplitudes to what is expected from the low-energy theorem is discussed. We relate the one-loop results to the structure coefficients of a low-energy expansion for the model-dependent part of the VCS amplitude recently defined by Fearing and Scherer. Finally we discuss the connection of our results with the generalized polarizabilities of the nucleon defined by Guichon, Liu and Thomas.

nucl-th↗
arXiv1993

K_S\rightarrow γγ, K_L\rightarrowπ^0γγ$ and Unitarity

Agreement between the experimental value $Γ(K_S\rightarrow γγ)$ and the number predicted via a one-loop chiral perturbation theory calculation has been cited as a success for the latter. On the other hand the one-loop prediction for the closely related process $K_L\rightarrow π^0γγ$ has been found to be a factor three below the experimental value. Using the inputs of unitarity and dispersion relations, we demonstrate the importance of higher order loop effects to both of these processes.

hep-ph↗