Measurement of the $p(e,e'\pi^+)n$ reaction close to threshold and at   low $Q^2$
  The cross section of the $p(e,e'\pi^+)n$ reaction has been measured for five kinematic settings at an invariant mass of $W = 1094$ MeV and for a four-momentum transfer of $Q^2 = 0.078$ (GeV/$c$)$^2$. The measurement has been performed at MAMI using a new short-orbit spectrometer (SOS) of the A1 collaboration, intended for detection of low-energy pions. The transverse and longitudinal cross section terms were separated using the Rosenbluth method and the transverse-longitudinal interference term has been determined from the left-right asymmetry. The experimental cross section terms are compared with the calculations of three models: DMT2001, MAID2007 and $\chi$MAID. The results show that we do not yet understand the dynamics of the fundamental pion. 
A1 Collaboration: I. Fri\v{s}\v{c}i\'c, P. Achenbach, C. Ayerbe   Gayoso, D. Baumann, R. B\"ohm, D. Bosnar, L. Debenjak, A. ...
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