Conveners
Low energy spin physics with lepton, photon and hadron probes
- Atsushi Tamii (Research Center for Nuclear Physics)
- Hideki Kohri (RCNP, Osaka University)
The J-PARC E42 is a dedicated experiment to search for an H-dibaryon near $\Lambda\Lambda$ and $\Xi^{-}p$ threshold. The H-dibaryon is the lightest $S=−2$ system which can be decomposed into a symmetric six-quark object made from $\textit{uuddss}$ quarks and two baryon states involving $\Lambda\Lambda$, $\Xi N$, and $\Sigma\Sigma$ components. E42 detector is highlighted by a large-acceptance...
The meson photoproduction is a useful tool to study baryon resonances.Especially, an $\eta$ meson is an isoscalar meson with $s\bar{s}$ components, so it is expected to couple with $\mathrm{N}^{*}$ states with large $s\bar{s}$ components. In previous experiments, the bump structure was seen above 2 GeV in differential cross sections of $\eta$ photoproduction. But in this energy region, many...
The transverse single-spin asymmetry in inclusive electron-nucleon scattering, e + N(S_T) -> e’ + X, represents a pure two-photon exchange observable and is of fundamental interest for exploring higher-order QED effects in electron scattering. We compute this observable in the resonance region, where excitation of Delta isobars occurs in both intermediate and final states. We employ a novel...
The $\eta d$ threshold structure $\mathcal{D}_{\eta d}$ with a spin parity of $1^-$ has been experimentally studied in the $\gamma d \to \pi^0 \eta d$ reaction at $E_\gamma \lt 1.15$ GeV. The structure is connected to the isoscalar $S$-wave two-body system between the nucleon $N$ and nucleon resonance $N(1535)1/2^-$, or the chiral partner candidate of $N$. By incorporating the known isovector...