2008/03/31 by Stefan Christlmeier, Harald W. Grießhammer, Harald W. Griesshammer
Physics and Astronomy · #Magnetic confinement fusion research #Nuclear physics research studies #Quantum Chromodynamics and Particle Interactions #nucl-th
paper · pdf · doi:10.1103/physrevc.77.064001
published as Phys.Rev.C77:064001,2008 · 30 pages LaTeX2e, including 10 figures as 34 .eps files embedded with includegraphicx. Increased figure sizes; contents identical to version approved for publication in Phys Rev C -- spelling and grammatical differences
arxiv created 2008/05/21 · openalex publication_date 2008/06/11 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In view of its relation to Big Bang nucleosynthesis and a reported discrepancy between nuclear models and data taken at S-DALINAC, electro-induced deuteron breakup 2H(e,e'p)n is studied at momentum transfer q<100 MeV and close to threshold in the low-energy nuclear effective field theory without dynamical pions, EFT(\ensuremathπ\phantom\rule-0.5em0ex/). The result at next-to-next-to-leading order (N2LO) for electric dipole currents and at next-to-leading order (NLO) for magnetic ones converges order-by-order better than quantitatively predicted and contains no free parameter. It is at this order determined by simple, well-known observables. Decomposing the triple differential cross section into the longitudinal-plus-transverse (L+T), transverse-transverse (TT), and longitudinal-transverse interference (LT) terms, we find excellent agreement with a potential-model calculation by Arenh"ovel and co-workers, based on the Bonn potential. Theory and data also agree well on \ensuremathσL+T. There is however no space on the theory side for the discrepancy of up to 30%(3\ensuremathσ) between theory and experiment in \ensuremathσLT. From universality of EFT(\ensuremathπ\phantom\rule-0.5em0ex/), we conclude that no theoretical approach with the correct deuteron asymptotic wave function can explain the data. Undetermined short-distance contributions that could affect \ensuremathσLT enter only at high orders (i.e., at the few-percent level). We notice some issues with the kinematics and normalization of the data reported.