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arXiv · 0706.4023

Role of the Delta(1232) in pion-deuteron scattering at threshold within chiral effective field theory

V. Baru·J. Haidenbauer·C. Hanhart·A. Kudryavtsev·V. Lensky·U. -G. Meißner
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Abstract

We investigate the role of the delta isobar in the reaction $πd\to πd$ at threshold in chiral effective field theory. We discuss the corresponding power counting and argue that this calculation completes the evaluation of diagrams up to the order (m_pi/M_N)^(3/2), with m_pi (M_N) for the pion (nucleon) mass. The net effect of all delta contributions at this order to the pion-deuteron scattering length is (2.4 +/- 0.4)x 10^(-3) m_pi^{-1}.

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V. Baru, J. Haidenbauer, C. Hanhart, A. Kudryavtsev, V. Lensky, U. -G. Meißner. 2007-06-27. Role of the Delta(1232) in pion-deuteron scattering at threshold within chiral effective field theory. https://doi.org/10.1016/j.physletb.2007.10.063

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