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Measurement of the R$_{LT}$ response function for $pi^0$ electroproduction at $Q^2$ = 0.070 (GeV/c)$^2$ in the $NtoDelta$ transition}

101   0   0.0 ( 0 )
 نشر من قبل Sparveris Nikolaos
 تاريخ النشر 2002
  مجال البحث
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Quadrupole amplitudes in the $gamma^{*}NtoDelta$ transition are associated with the issue of nucleon deformation. A search for these small amplitudes has been the focus of a series of measurements undertaken at Bates/MIT by the OOPS collaboration. We report on results from H$(e,e^prime p)pi^0$ data obtained at $Q^2= 0.070$ (GeV/c)$^2$ and invariant mass of W=1155 MeV using the out-of-plane detection technique with the OOPS spectrometers. The $sigma_{LT}$ and $sigma_{T}+epsiloncdot$ $sigma_{L}$ response functions were isolated. These results, along with those of previous measurements at $W$=1172 MeV and $Q^2= 0.127$ (GeV/c)$^2$, aim in elucidating the interplay between resonant and non resonant amplitudes.



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