First measurement of target and double spin asymmetries for e→p→→epπ0 in the nucleon resonance region above the Δ(1232)

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The exclusive channel $\stackrel{\ensuremath{\rightarrow}}{p}(\stackrel{\ensuremath{\rightarrow}}{e},{e}^{'}p){\ensuremath{\pi}}^{0}$ was studied in the first and second nucleon resonance regions in the ${Q}^{2}$ range from $0.187$ to $0.770 {\mathrm{GeV}}^{2}$ at Jefferson Lab using the CEBAF Large Acceptance Spectrometer. Longitudinal target and beam-target asymmetries were extracted over a large range of center-of-mass angles of the ${\ensuremath{\pi}}^{0}$ and compared to the unitary isobar model MAID, the dynamic model by Sato and Lee, and the dynamic model DMT. A strong sensitivity to individual models was observed, in particular for the target asymmetry and in the higher invariant mass region. This data set, once included in the global fits of the above models, is expected to place strong constraints on the electrocoupling amplitudes ${A}_{1/2}$ and ${S}_{1/2}$ for the Roper resonance $N(1400){P}_{11}$ and the $N(1535){S}_{11}$ and $N(1520){D}_{13}$ states.