Measurements of the transverse-momentum-dependent cross sections of J/ψ production at mid-rapidity in proton+proton collisions at s=510 and 500 GeV with the STAR detector

We present measurements of the differential cross sections of inclusive $J/\ensuremath{\psi}$ meson production as a function of transverse momentum (${p}_{T}^{J/\ensuremath{\psi}}$) using the ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ and ${e}^{+}{e}^{\ensuremath{-}}$ decay channels in $\mathrm{proton}+\mathrm{proton}$ collisions at center-of-mass energies of 510 and 500 GeV, respectively, recorded by the STAR detector at the Relativistic Heavy Ion Collider. The measurement from the ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ channel is for $0<{p}_{T}^{J/\ensuremath{\psi}}<9\text{ }\text{ }\mathrm{GeV}/c$ and rapidity range $|{y}^{J/\ensuremath{\psi}}|<0.4$, and that from the ${e}^{+}{e}^{\ensuremath{-}}$ channel is for $4<{p}_{T}^{J/\ensuremath{\psi}}<20\text{ }\text{ }\mathrm{GeV}/c$ and $|{y}^{J/\ensuremath{\psi}}|<1.0$. The $\ensuremath{\psi}(2S)$ to $J/\ensuremath{\psi}$ ratio is also measured for $4<{p}_{T}^{\text{meson}}<12\text{ }\text{ }\mathrm{GeV}/c$ through the ${e}^{+}{e}^{\ensuremath{-}}$ decay channel. Model calculations, which incorporate different approaches toward the $J/\ensuremath{\psi}$ production mechanism, are compared with experimental results and show reasonable agreement within uncertainties.

Hali tarjima qilinmagan