Study of a possibility of observation of hidden-bottom pentaquark resonances in bottomonium photoproduction on protons and nuclei near threshold

Understand

We study the $\Upsilon(1S)$ meson photoproduction on protons and nuclei at the near-threshold center-of-mass energies below 11.4 GeV (or at the corresponding photon laboratory energies $E_{\gamma}$ below 68.8 GeV).

• We calculate the absolute excitation functions for the non-resonant and resonant photoproduction of $\Upsilon(1S)$ mesons off protons at incident photon laboratory energies of 63--68 GeV by accounting for direct (${\gamma}p \to {\Upsilon(1S)}p$) and two-step (${\gamma}p \to P^+_b(11080,11125,11130) \to {\Upsilon(1S)}p$) $\Upsilon(1S)$ production channels within different scenarios for the non-resonant total cross section of elementary reaction ${\gamma}p \to {\Upsilon(1S)}p$ and for branching ratios of the decays $P^+_b(11080,11125,11130) \to {\Upsilon(1S)}p$.
• We also calculate an analogous functions for photoproduction of $\Upsilon(1S)$ mesons on $^{12}$C and $^{208}$Pb target nuclei in the near-threshold center-of-mass beam energy region of 9.0--11.4 GeV by considering respective incoherent direct (${\gamma}N \to {\Upsilon(1S)}N$) and two-step (${\gamma}p \to P^+_b(11080,11125,11130) \to {\Upsilon(1S)}p$, ${\gamma}n \to P^0_b(11080,11125,11130) \to {\Upsilon(1S)}n$) $\Upsilon(1S)$ production processes within a nuclear spectral function approach.
• We show that a detailed scan of the $\Upsilon(1S)$ total photoproduction cross section on a proton and nuclear targets in the near-threshold energy region in future high-precision experiments at the proposed high-luminosity electron-ion colliders EIC and EicC in the U.S.