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Related papers: Nothing anomalous about two-loop HBCPT: consistenc…

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We investigate pion photoproduction off the proton in a manifestly gauge-invariant chiral unitary extension of chiral perturbation theory. In a first step, we consider meson-baryon scattering taking into account all next-to-leading order…

Nuclear Theory · Physics 2013-05-30 Maxim Mai , Peter C. Bruns , Ulf-G. Meissner

We analyze polarized Compton scattering which provides information on the spin-structure of the nucleon. For scattering processes with photon energies up to 100 MeV the spin-structure dependence can be encoded into four independent…

Nuclear Theory · Physics 2009-10-30 Thomas R. Hemmert , Barry R. Holstein , Joachim Kambor , Germar Knoechlein

(New version with some expanded discussion; figures and minor typos corrected.) We have calculated the contribution proportional to the fifth power of the pion mass in the chiral expansion of the nucleon mass in two flavour HBCPT. Only one…

High Energy Physics - Phenomenology · Physics 2009-10-31 Judith A. McGovern , Michael C. Birse

The electric ($\alpha_\pi$) and magnetic ($\beta_\pi$) Compton polarizabilities of both the charged and the neutral pion are of fundamental interest in the low-energy sector of quantum chromodynamics (QCD). Pion polarizabilities affect the…

High Energy Physics - Phenomenology · Physics 2019-06-26 Murray Moinester , Stefan Scherer

Multi-particle states with additional pions are expected to be a non-negligible source of the excited-state contamination in lattice simulations at the physical point. It is shown that baryon chiral perturbation theory (ChPT) can be…

High Energy Physics - Lattice · Physics 2018-04-18 Oliver Bar

These proceedings sketch how combining recent theoretical advances with data from the new generation of high-precision Compton scattering experiments on both the proton and few-nucleon systems offers fresh, detailed insight into the Physics…

Nuclear Theory · Physics 2009-11-10 Harald W. Griesshammer

We assess the energy limit up to which Heavy Baryon Chiral Perturbation Theory (HBChPT) can be applied to the process of neutral pion photoproduction from the proton by analyzing the latest data collected by the MAMI/A2 collaboration at…

Nuclear Theory · Physics 2013-07-01 Cesar Fernandez-Ramirez

We present a calculation of the fourth-order (NLO) contribution to spin-dependent Compton scattering in heavy-baryon chiral perturbation theory, and we give results for the four spin polarisabilities. No low-energy constants, except for the…

High Energy Physics - Phenomenology · Physics 2009-10-31 K. B. Vijaya Kumar , Judith A. McGovern , Michael C. Birse

We study low-energy nucleon Compton scattering in the framework of baryon chiral perturbation theory (B$\chi$PT) with pion, nucleon, and $\Delta$(1232) degrees of freedom, up to and including the next-to-next-to-leading order (NNLO). We…

High Energy Physics - Phenomenology · Physics 2010-01-06 V. Lensky , V. Pascalutsa

We calculate the T-matrices of kaon-nucleon ($KN$) and antikaon-nucleon ($\overline{K}N$) scattering to one-loop order in SU(3) heavy baryon chiral perturbation theory (HB$\chi$PT). The low-energy constants (LECs) and their combinations are…

Nuclear Theory · Physics 2017-01-20 Bo-Lin Huang , Yun-De Li

We carry out a Lorentz gauge evaluation of the single-soft photon bremsstrahlung radiative corrections to the unpolarized elastic lepton-proton scattering cross section at low energies using the framework of heavy baryon chiral effective…

High Energy Physics - Phenomenology · Physics 2025-08-12 Bhoomika Das , Rakshanda Goswami , Pulak Talukdar , Udit Raha , Fred Myhrer

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…

High Energy Physics - Phenomenology · Physics 2011-09-13 B. Borasoy , B. R. Holstein

We consider the spin-averaged nucleon forward Compton scattering amplitude in heavy baryon chiral perturbation theory including all terms to order ${\cal O} (q^4)$. The chiral prediction for the spin-averaged forward Compton scattering…

High Energy Physics - Phenomenology · Physics 2015-06-25 V. Bernard , N. Kaiser , Ulf-G. Meißner , A. Schmidt

We present an exact analytical evaluation of the two-photon exchange (TPE) correction to the elastic lepton-proton differential scattering cross section at low-energies within the framework of heavy-baryon chiral perturbation theory. Our…

High Energy Physics - Phenomenology · Physics 2026-01-22 Rakshanda Goswami , Pulak Talukdar , Bhoomika Das , Udit Raha , Fred Myhrer

We present the results of a systematic leading order calculation of hyperon Compton scattering and extract the forward spin polarizability gamma0 of hyperons within the framework of SU(3) heavy baryon chiral perturbation theory (HBChPT).…

High Energy Physics - Phenomenology · Physics 2011-10-20 K. B. Vijaya Kumar , Amand Faessler , Thomas Gutsche , Barry R. Holstein , Valery E. Lyubovitskij

The electric ${\alpha}_{\pi}$ and magnetic $\beta_{\pi}$ charged pion Compton polarizabilities are of fundamental interest in the low-energy sector of quantum chromodynamics (QCD).They are directly linked to the phenomenon of spontaneously…

High Energy Physics - Phenomenology · Physics 2018-06-19 Murray Moinester

A measurement of parity-violating spin-dependent gamma proton Compton scattering will provide a theoretically clean determination of the parity-violating pion-nucleon coupling constant $h_{\pi NN}^{(1)}$. We calculate the leading…

Nuclear Theory · Physics 2009-10-31 Paulo F. Bedaque , Martin J. Savage

The low-energy effective theory of nuclear physics based on chiral symmetry is reviewed. Topics discussed include the nucleon-nucleon force, few-body potentials, isospin violation, pion-deuteron scattering, proton-neutron radiative capture,…

High Energy Physics - Phenomenology · Physics 2009-10-30 U. van Kolck

We compute the charged pion loop contribution to the light-by-light scattering amplitude for off-shell photons in chiral perturbation theory through next-to-leading order (NLO). We show that NLO contributions are relatively more important…

High Energy Physics - Phenomenology · Physics 2013-05-30 Kevin T. Engel , Hiren H. Patel , Michael J. Ramsey-Musolf

After a general introduction to the structure of effective field theories, the main ingredients of chiral perturbation theory are reviewed. Applications include the light quark mass ratios and pion-pion scattering to two-loop accuracy. In…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gerhard Ecker