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Sensitivity of tensor analyzing power in the process $d+p\to d+X$ to the longitudinal isoscalar form factor of the Roper resonance electroexcitation

E. Tomasi-Gustafsson·M. P. Rekalo·R. Bijker·A. Leviatan·F. Iachello
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Abstract

The tensor analyzing power of the process $d + p \to d + X$, for forward deuteron scattering in the momentum interval 3.7 to 9 GeV/c, is studied in the framework of $ω$ exchange in an algebraic collective model for the electroexcitation of nucleon resonances. We point out a special sensitivity of the tensor analyzing power to the isoscalar longitudinal form factor of the Roper resonance excitation. The main argument is that the $S_{11}(1535)$, $D_{13}(1520)$ and $S_{11}(1650)$ resonances have only isovector longitudinal form factors. It is the longitudinal form factor of the Roper excitation, which plays an important role in the $t-$dependence of the tensor analyzing power. We discuss possible evidence of swelling of hadrons with increasing excitation energy.

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E. Tomasi-Gustafsson, M. P. Rekalo, R. Bijker, A. Leviatan, F. Iachello. 1999-11-09. Sensitivity of tensor analyzing power in the process $d+p\to d+X$ to the longitudinal isoscalar form factor of the Roper resonance electroexcitation. https://doi.org/10.1103/physrevc.59.1526

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