Electromagnetic processes in few-nucleon systems with the Chiral Effective Field Theory
Dr. Dagmara Rozpedzik
Jagiellonian University, Krakow, Poland
Monday, May 18, 2015
4:00 - 5:00 pm EST
Nieuwland Science Hall, Room 124
Chiral Effective Field Theory provides a systematic and model-independent framework for studying hadronicprocesses in accordance with the spontaneously broken approximate chiral symmetry of the QCD. This approach isa powerful tool for the derivation of the nuclear forces and current operators. Chiral nucleon-nucleon potentialshave been known for a long time up to the fourth order. However, the potential regularization used within thisframework in many cases leads to a large uncertainty in the predictions.
A new approach to the regularization of the chiral nucleon-nucleon potentials derived in the chiral effective fieldtheory up to fifth order has been proposed recently. The new potentials do not require the additional spectralfunction regularization to cut off the short-range components of the two-pion exchange and make use of the low-energy constants determined from pion-nucleon scattering.
In this talk, a novel procedure for estimating the theoretical uncertainty from the truncation of the chiralexpansion that replaces previous reliance on cutoff variation will be introduced. The results for low energyelectromagnetic reactions obtained with the old and novel approaches to the regularization of the potentials willbe presented. The differential cross section and many polarization observables will be shown. The calculationswere performed for the selected chiral orders (up to fifth) and for all observables the procedure for estimating thetheoretical uncertainties was applied. The results will be compared with those based on the AV18 potential withthe corresponding meson exchange currents.