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Related papers: Effective theory of the Delta(1232) in Compton sca…

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A new power-counting scheme for a chiral effective field theory that includes Delta degrees of freedom is briefly described and applied to the nucleon Compton scattering.

Nuclear Theory · Physics 2007-05-23 V. Pascalutsa , D. R. Phillips

As guideline for forthcoming experiments, we present predictions from Chiral Effective Field Theory for polarized cross sections in low energy Compton scattering for photon energies below 170 MeV, both on the proton and on the neutron.…

Nuclear Theory · Physics 2009-11-10 Robert P. Hildebrandt , Harald W. Griesshammer , Thomas R. Hemmert

We report on a chiral effective field theory calculation of Compton scattering from the proton. Our calculation includes pions, nucleons, and the Delta(1232) as explicit degrees of freedom. It uses the "delta expansion", and so implements…

We analyse the proton Compton-scattering differential cross section for photon energies up to 325 MeV using Chiral Effective Field Theory and extract new values for the electric and magnetic polarisabilities of the proton. Our EFT treatment…

Nuclear Theory · Physics 2013-01-25 Judith A. McGovern , Daniel R. Phillips , Harald W. Grießhammer

Previous calculations of the polarizabilities of the nucleon within the framework of heavy baryon chiral perturbation theory have included the contribution of the $\Delta$(1232) only its effect on various contact terms or have been…

High Energy Physics - Phenomenology · Physics 2008-11-26 Thomas R. Hemmert , Barry R. Holstein , Joachim Kambor

Chiral Effective Field Theory is for photon energies up to 200 MeV the tool to accurately determine the polarisabilities of the neutron from deuteron Compton scattering. A multipole analysis reveals that dispersive effects from an explicit…

Nuclear Theory · Physics 2008-11-26 Harald W. Griesshammer

We present a projector formalism which allows to define dynamical polarizabilities of the nucleon from a multipole expansion of the nucleon Compton amplitudes. We give predictions for the energy dependence of these dynamical…

We investigate the dependence of polarisation observables in elastic deuteron Compton scattering below the pion production threshold on the spin-independent and spin-dependent iso-scalar dipole polarisabilities of the nucleon. The…

Nuclear Theory · Physics 2012-03-28 Harald W. Griesshammer , Deepshikha Shukla

Several conceptual points concerning the inclusion of the $\Delta$(1232) resonance in the framework of chiral effective-field theory are discussed, with an emphasis on the problem of power counting in the baryon sector in general. I also…

Nuclear Theory · Physics 2014-11-20 Vladimir Pascalutsa

We examine elastic Compton scattering off the deuteron for photon energies between 50 MeV and 100 MeV in the framework of chiral effective field theories to next-to-leading order. We compare one theoretical scheme with only pions and…

Based on Compton scattering and meson photoproduction data the polarizabilities of the nucleon are precisely studied and well understood due to recent experimental and theoretical work based on nonsubtracted dispersion relations. The {\it…

High Energy Physics - Phenomenology · Physics 2014-08-01 Martin Schumacher

An effective field theory is used to give a model-independent description of Compton scattering at energies comparable to the pion mass. The amplitudes for scattering on the proton and the deuteron, calculated to fourth order in small…

Nuclear Theory · Physics 2008-11-26 S. R. Beane , M. Malheiro , J. A. McGovern , D. R. Phillips , U. van Kolck

Polarized Compton scattering on the deuteron is studied in nuclear effective field theory. A set of tensor structures is introduced to define 12 independent Compton amplitudes. The scalar and vector amplitudes are calculated up to ${\cal…

Nuclear Theory · Physics 2009-11-10 Jiunn-Wei Chen , Xiangdong Ji , Yingchuan Li

Deuteron Compton scattering is calculated to $\mathcal{O}(Q^2)$ in pionless effective field theory using a dibaryon approach. The vector amplitude, which was not included in the previous pionless calculations, contributes to the cross…

Nuclear Theory · Physics 2009-11-10 Jiunn-Wei Chen , Xiangdong Ji , Yingchuan Li

Compton scattering on light nuclei ($A=2,3$) has emerged as an effective avenue to search for signatures of neutron polarizabilities, both spin--independent and spin--dependent ones. In this discussion I will focus on the theoretical aspect…

Nuclear Theory · Physics 2015-05-14 Deepshikha Shukla

The differential cross section for gamma-deuteron Compton scattering is computed to next-to-leading order (NLO) in an effective field theory that describes nucleon-nucleon interactions below the pion production threshold. Contributions at…

Nuclear Theory · Physics 2008-11-26 Jiunn-Wei Chen , Harald W. Griesshammer , Martin J. Savage , Roxanne P. Springer

In this sketch, I focus on Physics and formalism behind dynamical polarisabilities, a new tool to test and interpret quantitative predictions about the low-energy degrees of freedom inside the nucleon from the multipoles of Compton…

Nuclear Theory · Physics 2007-05-23 Harald W. Griesshammer

A brief review of Compton scattering off the deuteron in Chiral Effective Field Theory, including gauge invariance and the correct Thomson limit. We model-independently determine the iso-scalar, spin-independent dipole polarisabilities of…

Nuclear Theory · Physics 2017-08-23 Harald W. Griesshammer

Compton scattering provides important insight into the structure of the nucleon. For photons up to about 300 MeV, it is parameterised by six dynamical dipole polarisabilities which characterise the response of the nucleon to a monochromatic…

Nuclear Theory · Physics 2012-12-12 Harald W. Griesshammer , Judith A. McGovern , Daniel R. Phillips , Gerald Feldman

We discuss the application of an effective field theory (EFT) which incorporates the chiral symmetry of QCD to Compton scattering from the proton and deuteron. We describe the chiral EFT analysis of the proton Compton scattering database…

Nuclear Theory · Physics 2015-06-11 Daniel R. Phillips , Judith A. McGovern , Harald W. Griesshammer
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