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We propose to create a secondary beam of neutral kaons in Hall D at Jefferson Lab to be used with the GlueX experimental setup for strange hadron spectroscopy. The superior CEBAF electron beam will enable a flux on the order of $1\times 10^4~K_L/sec$, which exceeds the flux of that previously attained at SLAC by three orders of magnitude. The use of a deuteron target will provide first measurements ever with neutral kaons on neutrons. The experiment will measure both differential cross sections and self-analyzed polarizations of the produced $\Lambda$, $\Sigma$, $\Xi$, and $\Omega$ hyperons using the GlueX detector at the Jefferson Lab Hall D. The measurements will span CM $\cos\theta$ from $-0.95$ to 0.95 in the range W = 1490 MeV to 2500 MeV. The new data will significantly constrain the partial wave analyses and reduce model-dependent uncertainties in the extraction of the properties and pole positions of the strange hyperon resonances, and establish the orbitally excited multiplets in the spectra of the $\Xi$ and $\Omega$ hyperons. Comparison with the corresponding multiplets in the spectra of the charm and bottom hyperons will provide insight into he accuracy of QCD-based calculations over a large range of masses. The proposed facility will have a defining impact in the strange meson sector through measurements of the final state $K\pi$ system up to 2 GeV invariant mass. This will allow the determination of pole positions and widths of all relevant $K^\ast(K\pi)$ $S$-,$P$-,$D$-,$F$-, and $G$-wave resonances, settle the question of the existence or nonexistence of scalar meson $\kappa/K_0^\ast(700)$ and improve the constrains on their pole parameters. Subsequently improving our knowledge of the low-lying scalar nonet in general., Comment: Final version of the KLF Proposal [C12-19-001] approved by JLab PAC48. The intermediate version of the proposal was posted in arXiv:1707.05284 [hep-ex]. 103 pages, 52 figures, 8 tables, 324 references. Several typos were fixed

We perform a matching of the two loop-chiral perturbation theory representation of the scalar Kpi form factor to a dispersive one. Knowing the value of F_K/F_pi and f_+(0) in the Standard Model (SM) allows to determine two O(p^6) LECs, the slope of the scalar form factor and the deviation of the Callan-Treiman theorem. Going beyond the SM and assuming the knowledge of the slope of the scalar form factor from experiment, the matching allows us to determine the ratio of F_K/F_pi, f_+(0), a certain combination of non-standard couplings, the deviation of the Callan-Treiman theorem and the two O(p^6) LECs., Comment: 13 pages, 1 figure, typos corrected, discussion slightly extended, accepted for publication in Phys. Lett. B

Theoretical as well as experimental progress has been made in the last decade in describing the properties of baryons. In this review I will mostly report on the theoretical issues. Two non-perturbative methods are privileged frameworks for studying these properties in the low energy domain: chiral perturbation theory, the effective field theory of the Standard Model at energies below 1 GeV and lattice QCD. I will mainly concentrate here on the first one but I will also discuss the complementarity of the two methods. Chiral extrapolations for lattice simulations of some nucleon properties will be investigated. I will then concentrate on processes involving at most two nucleons, describing for example pion-nucleon and pion-deuteron scattering, pion photo- and electroproduction off the nucleon and the deuteron and doubly virtual Compton scattering. Three flavor calculations will also be reviewed., Comment: commissioned article for Prog. Nucl. Part. Phys

We study the extraction of Delta-resonance parameters from lattice data for small quark masses, corresponding to the case of an unstable Delta. To this end, we calculate the spectrum of the correlator of two Delta-fields in a finite Euclidian box up-to-and-including O(epsilon^3) in the small scale expansion using infrared regularization. On the basis of our numerical study, we argue that the extraction of the parameters of the Delta-resonance (in particular, of the mass and the pion-nucleon-delta coupling constant) from the measured volume dependence of the lowest energy levels should be feasible., Comment: 20 pages, 8 postscript figures

We give a brief introduction to chiral perturbation theory in its various settings. We discuss some applications of recent interest including chiral extrapolations for lattice gauge theory., Comment: Commissioned article for Ann. Rev. Nucl. Part. Sci., 27 pp, 7 figs

We analyze the nucleon axial-vector coupling to two loops in chiral perturbation theory. We show that chiral extrapolations based on this representation require lattice data with pion masses below 300 MeV., Comment: 9 pp, 2 figs

We analyze the Fubini-Furlan-Rosetti sum rule in the framework of covariant baryon chiral perturbation theory to leading one-loop accuracy and including next-to-leading order polynomial contributions. We discuss the relation between the subtraction constants in the invariant amplitudes and certain low-energy constants employed in earlier chiral perturbation theory studies of threshold neutral pion photoproduction off nucleons. In particular, we consider the corrections to the sum rule due to the finite pion mass and show that below the threshold they agree well with determinations based on fixed-t dispersion relations. We also discuss the energy dependence of the electric dipole amplitude E_{0+}., Comment: 7 pages, 2 figs

We calculate the nucleon and the delta mass to fourth order in a covariant formulation of the small scale expansion. We analyze lattice data from the MILC collaboration and demonstrate that the available lattice data combined with our knowledge of the physical values for the nucleon and delta masses lead to consistent chiral extrapolation functions for both observables up to fairly large pion masses. This holds in particular for very recent data on the delta mass from the QCDSF collaboration. The resulting pion-nucleon sigma term is sigma_{piN} = 48.9 MeV. This first quantitative analysis of the quark-mass dependence of the structure of the Delta(1232) in full QCD within chiral effective field theory suggests that (the real part of) the nucleon-delta mass-splitting in the chiral limit, Delta_0 = 0.33 GeV, is slightly larger than at the physical point. Further analysis of simultaneous fits to nucleon and delta lattice data are needed for a precision determination of the properties of the first excited state of the nucleon., Comment: 11 pp, 2 figs, version accepted for publication in Phys. Lett. B

We discuss the use of cutoff methods in chiral perturbation theory. We develop a cutoff scheme based on the operator structure of the effective field theory that allows to suppress high momentum contributions in Goldstone boson loop integrals and by construction is free of the problems traditional cutoff schemes have with gauge invariance or chiral symmetries. As an example, we discuss the chiral expansion of the nucleon mass. Contrary to other claims in the literature we show that the mass of a nucleon in heavy baryon chiral perturbation theory has a well behaved chiral expansion up to effective Goldstone boson masses of 400 MeV when one utilizes standard dimensional regularization techniques. With the help of the here developed cutoff scheme we can demonstrate a well-behaved chiral expansion for the nucleon mass up to 600 MeV of effective Goldstone Boson masses. We also discuss in detail the prize, in numbers of additional short distance operators involved, that has to be paid for this extended range of applicability of chiral perturbation theory with cutoff regularization, which is usually not paid attention to. We also compare the fourth order result for the chiral expansion of the nucleon mass with lattice results and draw some conclusions about chiral extrapolations based on such type of representation., Comment: 19 pp, 8 figs

We present a Lorentz-invariant formulation of baryon chiral perturbation theory including spin-3/2 fields. Particular attention is paid to the projection on the spin-3/2 components of the delta fields. We also discuss the nucleon mass and the pion-nucleon sigma term., Comment: 9 pp, 1 fig

Some recent developments in the description of nuclear forces and few-nucleon dynamics derived from chiral effective field theory are reviewed., Comment: invited talk at the International Workshop SCGT 02 "Strong Coupling Gauge Theories and Effective Field Theories", 10-13 December 2002, Nagoya, Japan

The spin structure of the nucleon is analyzed in the framework of a Lorentz-invariant formulation of baryon chiral perturbation theory. The structure functions of doubly virtual Compton scattering are calculated to one-loop accuracy (fourth order in the chiral expansion). We discuss the generalization of the Gerasimov-Drell-Hearn sum rule, the Burkhardt-Cottingham sum rule and moments of these. We give predictions for the forward and the longitudinal-transverse spin polarizabilities of the proton and the neutron at zero and finite photon virtuality. A detailed comparison to results obtained in heavy baryon chiral perturbation theory is also given., Comment: 29 pp, 14 figs

We study the chiral loop corrections to the generalized Gerasimov-Drell-Hearn sum rule of the nucleon for finite photon virtuality in the framework of a Lorentz-invariant formulation of baryon chiral perturbation theory. We perform a complete one-loop calculation and obtain significant differences to previously found results based on the heavy baryon approach for the proton and neutron spin-dependent forward Compton amplitudes., Comment: 7 pp, 3 figs, published version, extended discussion, minor revisions

We review the current status of experimental and theoretical understanding of the axial nucleon structure at low and moderate energies. Topics considered include (quasi)elastic (anti)neutrino-nucleon scattering, charged pion electroproduction off nucleons and ordinary as well as radiative muon capture on the proton., Comment: 40 pp, uses iopart.cls, iopart10.clo, iopart12.clo

We investigate near threshold neutral pion photoproduction off protons to fourth order in heavy baryon chiral perturbation theory in the light of the new data from MAMI. We show that the unitarity cusp at the secondary \pi^+ n threshold is in agreement with expectations from the final state theorem. We also analyze the fourth order corrections to the P-wave low-energy theorems and show that potentially large Delta-isobar contributions are cancelled by sizeable pion loop effects. This solidifies the parameter free third order predictions, which are in excellent agreement with the data., Comment: 13 pp, LaTeX2e, updated version, using officially released data

We analyze a low-energy theorem of threshold pion electroproduction which allows one to determine the charge radius of the pion. We show that at the same order where the radius appears, pion loops induce a correction to the momentum dependence of the longitudinal dipole amplitude $L_{0+}^{(-)}$. This model-independent correction amounts to an increase of the pion charge radius squared from the electroproduction data by about 0.26~fm$^2$. It sheds light on the apparent discrepancy between the recent determination of the pion radius from electroproduction data and the one based on pion-electron scattering., Comment: 3 pp, REVTeX, uses epsf

We calculate ordinary and radiative muon capture on the proton in an effective field theory of pions, nucleons and delta isobars, working to third and second order in the small scale expansion respectively. Preceding calculations in chiral effective field theories only employed pion and nucleon degrees of freedom and were not able to reproduce the photon spectrum in the pioneering experiment of radiative muon capture on the proton from TRIUMF. For the past few years it has been speculated that the discrepancy between theory and experiment might be due to Delta(1232) related effects, which are only included via higher order contact interactions in the standard chiral approach. In this report we demonstrate that this speculation does not hold true. We show that contrary to expectations from naive dimensional analysis isobar effects on the photon spectrum and the total rate in radiative muon capture are of the order of a few percent, consistent with earlier findings in a more phenomenological approach. We further demonstrate that both ordinary and radiative muon capture constitute systems with a very well behaved chiral expansion, both in standard chiral perturbation theory and in the small scale expansion, and present some new ideas that might be at the bottom of the still unresolved discrepancy between theory and experiment in radiative muon capture. Finally we comment upon the procedure employed by the TRIUMF group to extract new information from their radiative muon capture experiment on the pseudoscalar form factor of the nucleon. We show that it is inconsistent with the ordinary muon capture data., Comment: 22 pp, RevTeX, uses epsf, 8 figs, enlarged version, discussion of ordinary muon capture on protons substantially enlarged, accepted for publication in Nucl.Phys.A, FZJ-IKP(TH)-2000-02

Single pion production off nucleons is studied in the framework of heavy baryon chiral perturbation theory to third order in the chiral expansion. Using total and some older differential cross section data to pin down the low-energy constants, most of the recent differential cross sections and angular correlation functions can be described as well as total cross sections at higher energies. We show that the contributions from the one loop graphs are essentially negligible and that the dominant terms at second and third order are related to pion-nucleon scattering graphs with one pion added. We also discuss the possibility of extracting the pion-pion S-wave scattering lengths from the unpolarized data., Comment: 57 pp, LaTeX file, 13 figures (uses epsf)

We study the low energy expansion of the nucleon's electroweak form factors in the framework of an effective chiral Lagrangian including pions, nucleons and the $Delta (1232)$. We work to third order in the so-called small scale expansion and compare the results with the ones previously obtained in the chiral expansion. In addition, these calculations serve as a first exploratory study of renormalization and decoupling within the small scale expansion., Comment: 21 pp, RevTeX, uses epsf, 4 figs, minor corrections, accepted for publication in Nucl.Phys.A

Photoproduction of neutral and charged pions off nucleons and deuterium has been precisely calculated in baryon chiral perturbation theory. I review the predictions with the accurate data that have become available over the last few years. Some progress in the description of neutral pion electroproduction off protons is also discussed., Comment: 17 pp, LaTeX, uses epsf and lamuphys.sty, invited plenary talk, Workshop on ``Chiral Dynamics: Theory and Experiment'', Mainz, September 1997, to appear in the proceedings

The momentum-space bosonization method is extended to the case of a Nambu--Jona-Lasinio type model with vector and axial-vector mesons. The method presented gives the possibility of deriving any meson vertex function to all orders in momenta and to the leading order in $1/N_c$. Two-point functions, which describe one-particle transitions to the hadronic vacuum, and meson self-energies are considered. We find new relations which generalize the well-known KSFR relation and both the first and the second Weinberg sum rules. These result from a consistent treatment of higher order terms in the momentum expansion., Comment: 11pp, TeX, CRN 93-57

We calculate the nucleons' electromagnetic polarizabilities in heavy baryon chiral perturbation theory including all terms to order ${\cal O} (q^4)$. The chiral prediction of the electric polarizabilities for the neutron and the proton are in good agreement with the data. In the case of the magnetic polarizabilities the big positive contribution from the $\Delta(1232)$ resonance is largely cancelled by a non--analytic loop contribution of the $\ln M_\pi$ type. This novel effect helps to understand the rather small empirical value of the nucleons' magnetic polarizability., Comment: 10 pp, TeX, BUTP-93/22 and CRN-93-39

We present an analysis of the octet baryon masses and the $\pi N$ and $KN$ $\sigma$--terms in the framework of heavy baryon chiral perturbation theory. At next-to-leading order, ${\cal O}(q^3)$, knowledge of the baryon masses and $\sigma_{\pi N}(0)$ allows to determine the three corresponding finite low--energy constants and to predict the the two $KN$ $\sigma$--terms $\sigma^{(1,2)}_{KN} (0)$. We also include the spin-3/2 decuplet in the effective theory. The presence of the non--vanishing energy scale due to the octet--decuplet splitting shifts the average octet baryon mass by an infinite amount and leads to infinite renormalizations of the low--energy constants. The first observable effect of the decuplet intermediate states to the baryon masses starts out at order $q^4$. We argue that it is not sufficient to retain only these but no other higher order terms to achieve a consistent description of the three--flavor scalar sector of baryon CHPT. In addition, we critically discuss an SU(2) result which allows to explain the large shift of $\sigma_{\pi N}(2M_\pi^2) - \sigma_{\pi N}(0)$ via intermediate $\Delta (1232)$ states., Comment: 18 pp, TeX, BUTP-93/05 and CRN-93-06

We investigate the momentum dependence of the extended Drell-Hearn-Gerasimov sum rule. An economical formalism is developed which allows to express the extended DHG sum rule in terms of a single virtual Compton amplitude in forward direction. Rigorous results for the small momentum evolution are derived from chiral perturbation theory within the one-loop approximation. Furthermore, we evaluate some higher order contributions arising from $\Delta(1232)$ intermediate states and relativistic corrections. (2 figures available upon request)., Comment: 12 pages, TeX, BUTP-92/51 and CRN-92-53