Investigation of the strange pentaquark candidate <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msubsup><mml:mi>P</mml:mi><mml:mrow><mml:mi>ψ</mml:mi><mml:mi>s</mml:mi></mml:mrow><mml:mi mathvariant="normal">Λ</mml:mi></mml:msubsup><mml:mo stretchy="false">(</mml:mo><mml:mn>4338</mml:mn><mml:msup><mml:mo stretchy="false">)</mml:mo><mml:mn>0</mml:mn></mml:msup></mml:math> recently observed by LHCb
K. Azizi, Y. Sarac, H. Sundu
Abstract
The recently observed strange pentaquark candidate, ${P}_{\ensuremath{\psi}s}^{\mathrm{\ensuremath{\Lambda}}}(4338{)}^{0}$, is investigated to provide information about its nature and substructure. To this end, its mass and width through the decay channels ${P}_{\ensuremath{\psi}s}^{\mathrm{\ensuremath{\Lambda}}}(4338{)}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}\mathrm{\ensuremath{\Lambda}}$ and ${P}_{\ensuremath{\psi}s}^{\mathrm{\ensuremath{\Lambda}}}(4338{)}^{0}\ensuremath{\rightarrow}{\ensuremath{\eta}}_{c}\mathrm{\ensuremath{\Lambda}}$ are calculated by applying two- and three-point QCD sum rules, respectively. The state is considered as a ${\mathrm{\ensuremath{\Xi}}}_{c}\overline{D}$ meson-baryon molecular structure with spin-parity quantum numbers ${J}^{P}={\frac{1}{2}}^{\ensuremath{-}}$. The obtained mass, ${m}_{{P}_{\ensuremath{\psi}s}^{\mathrm{\ensuremath{\Lambda}}}(4338{)}^{0}}=4338\ifmmode\pm\else\textpm\fi{}130\text{ }\text{ }\mathrm{MeV}$, and width, ${\mathrm{\ensuremath{\Gamma}}}_{{P}_{\ensuremath{\psi}s}^{\mathrm{\ensuremath{\Lambda}}}(4338{)}^{0}}=10.40\ifmmode\pm\else\textpm\fi{}\phantom{\rule{0ex}{0ex}}1.93\text{ }\text{ }\mathrm{MeV}$, are consistent with the experimental data within the presented uncertainties. This allows us to assign a ${\mathrm{\ensuremath{\Xi}}}_{c}\overline{D}$ molecular structure of ${J}^{P}={\frac{1}{2}}^{\ensuremath{-}}$ for the ${P}_{\ensuremath{\psi}s}^{\mathrm{\ensuremath{\Lambda}}}(4338{)}^{0}$ state.