Tensor polarized γ-deuteron Compton scattering in effective field theory

Abstract

The differential cross section for γ-deuteron Compton scattering from a tensor polarized deuteron is computed in an effective field theory. The first non-vanishing contributions to this differential cross section are the interference terms between the leading electric coupling diagrams and the subleading single potential pion exchange diagrams or the subleading magnetic moment coupling diagrams. At 90 • photon scattering angle, only the pion term contributes at this order to the tensor polarized differential cross section. This provides a clean way to study the photon pion dynamics in the two nucleon sector. The effect is measurable for photon energies between 40 and 80 MeV provided the uncertainty in the measured cross sections are <

Nuclear effective field theory: status and perspectives

“…For example, the charge, magnetic dipole and electric quadrupole form factors of the deuteron have been calculated to NLO by Kaplan et al (1999b). Other reactions include neutron radiative capture on the proton , deuteron Compton scattering and polarizability (Chen et al, 1998b,a;Chen, 1999), and neutrinodeuteron scattering (Butler and Chen, 2000). Generally, this approach has been successful for the low-energy properties of the deuteron, both in comparison with data (2013) for proton (blue) and neutron (red), where statistic, systematic, and theory errors were added in quadrature.…”

From Hadrons to Nuclei: Crossing the Border

“…The fact that the KSW power-counting allows for all calculations to be performed analytically with dimensional regularization means that it is very easy to perform gauge invariant calculations for processes involving photons and other gauge fields. In particular, ed scattering has been calculated up to NLO 52 , γd → γd Compton scattering has been computed (both for unpolarized and tensor-polarized targets) up to NLO 120,121 , the polarizabilities of the deuteron have been computed to high orders 122 , parity violation in np → dγ radiative capture has been explored 123 , and also parity violation in ed scattering due to the deuteron anapole moment has been investigated 124,125 . Calculations with perturbative pions have also been performed in the three-body sector 126 .…”

Dissecting deuteron Compton scattering I: The observables with polarised initial states

“…Often, observables are expressed not in terms of the degrees of deuteron vector and tensor polarisations, but via the occupation numbers p ±,0 of a state quantised along d. From Eq. (2.2), the density matrix of a pure deuteron state |M d is: The first tensor observable was constructed by Chen [11], and also used by Karakowski and Miller [12,13]. His definition of a cross section combination for an unpolarised beam on a deuteron which is tensor polarised along the z axis translates into the observables of Eq.…”

“…The first tensor observable was constructed by Chen [11], and also used by Karakowski and Miller [12,13]. His definition of a cross section combination for an unpolarised beam on a deuteron which is tensor polarised along the z axis translates into the observables of Eq.…”

“…While several single and double polarisation observables have been constructed and their sensitivity to the nucleon polarisabilities explored [6][7][8][9][10], no systematic study of vector and tensor polarisation observables exists. Only one tensor observable has been considered explicitly, namely for an unpolarised beam [11][12][13]. What is more, some deuteron "vector" observables which were defined analogous to the spin- 1 2 case will be shown to actually receive contributions from both vector and tensor polarisations.…”