Effects of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>N</mml:mi><mml:mrow><mml:mo>(</mml:mo><mml:mn>2080</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:msup><mml:mrow><mml:mn>3</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:mrow><mml:mo>−</mml:mo></mml:msup></mml:mrow></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>N</mml:mi><mml:mrow><mml:mo>(</mml:mo><mml:mn>2270</mml:mn><mml:mo>)</mml:mo></mml:mrow><mml:msup><mml:mrow><mml:mn>3</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:mrow><mml:mo>−</mml:mo></mml:msup></mml:mrow></mml:math> molecules on <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mi>K</mml:mi><mml:mo>*</mml:mo></mml:msup><mml:mi mathvariant="normal">Σ</mml:mi></mml:mrow></mml:math> photoproduction

Abstract

In our previous work [Phys. Rev. C 98, 045209 (2018)], the available differential cross-section data for $\ensuremath{\gamma}p\ensuremath{\rightarrow}{K}^{*+}{\mathrm{\ensuremath{\Sigma}}}^{0}$ and $\ensuremath{\gamma}p\ensuremath{\rightarrow}{K}^{*0}{\mathrm{\ensuremath{\Sigma}}}^{+}$ have been analyzed within an effective Lagrangian approach. It was found that one needs to introduce the $s$-channel $\mathrm{\ensuremath{\Delta}}(1905){5/2}^{+}$ resonance exchange besides the $t$-channel $K, \ensuremath{\kappa}$, and ${K}^{*}$ exchanges, the $s$-channel $N$ and $\mathrm{\ensuremath{\Delta}}$ exchanges, the $u$-channel $\mathrm{\ensuremath{\Lambda}}, \mathrm{\ensuremath{\Sigma}}$, and ${\mathrm{\ensuremath{\Sigma}}}^{*}$ exchanges, and the generalized contact term in constructing the reaction amplitudes to describe the data. In the present work, we reanalyze the available data for $\ensuremath{\gamma}p\ensuremath{\rightarrow}{K}^{*+}{\mathrm{\ensuremath{\Sigma}}}^{0}$ and $\ensuremath{\gamma}p\ensuremath{\rightarrow}{K}^{*0}{\mathrm{\ensuremath{\Sigma}}}^{+}$ by considering the contributions from the $N(2080){3/2}^{\ensuremath{-}}$ and $N(2270)3/{2}^{\ensuremath{-}}$ molecules instead of any nucleon resonances in the $s$ channel, where the $N(2080)3/{2}^{\ensuremath{-}}$ was proposed to be a ${K}^{*}\mathrm{\ensuremath{\Sigma}}$ molecule as the strange partner of the ${P}_{c}^{+}(4457)$ hadronic molecular state, and the $N(2270)3/{2}^{\ensuremath{-}}$ was assumed to be a ${K}^{*}{\mathrm{\ensuremath{\Sigma}}}^{*}$ molecule as the strange partner of the ${\overline{D}}^{*}{\mathrm{\ensuremath{\Sigma}}}_{c}^{*}$ bound states that are predicated as members in the same heavy-quark spin symmetry multiplet as the ${P}_{c}$ states. It turns out that all the available cross-section data can be well reproduced, indicating that the molecular structures of the possible $N(2080){3/2}^{\ensuremath{-}}$ and $N(2270)3/{2}^{\ensuremath{-}}$ states are compatible with the available data for ${K}^{*}\mathrm{\ensuremath{\Sigma}}$ photoproduction reactions. Further analysis shows that for both $\ensuremath{\gamma}p\ensuremath{\rightarrow}{K}^{*+}{\mathrm{\ensuremath{\Sigma}}}^{0}$ and $\ensuremath{\gamma}p\ensuremath{\rightarrow}{K}^{*0}{\mathrm{\ensuremath{\Sigma}}}^{+}$ reactions, the $N(2080){3/2}^{\ensuremath{-}}$ exchange provides dominant contributions to the cross sections in the near-threshold energy region, and significant contributions from the $N(2270)3/{2}^{\ensuremath{-}}$ exchange to the cross sections in the higher energy region are also found. Predictions of the beam asymmetry $\mathrm{\ensuremath{\Sigma}}$, target asymmetry $T$, and recoil baryon asymmetry $P$ are presented and compared with those from our previous work. Measurements of the data on these observables are called on to further constrain the reaction mechanisms of ${K}^{*}\mathrm{\ensuremath{\Sigma}}$ photoproduction reactions and to verify the molecular scenario of the $N(2080){3/2}^{\ensuremath{-}}$ and $N(2270)3/{2}^{\ensuremath{-}}$ states.

Topics & Concepts