Jul 4 – 11, 2018
COEX, SEOUL
Asia/Seoul timezone

Measurement of the psi(2S) to J/psi cross section ratio in photoproduction with the ZEUS detector at HERA

Jul 6, 2018, 6:30 PM
2h
COEX, SEOUL

COEX, SEOUL

Poster Strong Interactions and Hadron Physics POSTER

Speaker

Aleksander Zarnecki (University of Warsaw (PL))

Description

The exclusive photoproduction reaction $\gamma p -> \psi(2S) p$ has been studied with the ZEUS detector in $ep$ collisions at HERA using an integrated luminosity of 350 pb$^{-1}$, in the kinematic range 30 $< W <$ 180 GeV, $Q^2$ < 1 GeV$^2$, $|t|$ < 5 GeV$^2$, where $W$ is the photon proton centre-of-mass energy, $Q^2$ is the photon virtuality and t is the four-momentum transfer at the proton vertex. The $\psi(2S)$ mesons were identified via the decay channels: $\psi(2S) -> \mu^+\mu^-$ and $J/\psi \pi^+\pi^-$ with $J/\psi -> \mu^+\mu^-$. The ratio of the production cross sections $R = \sigma(\psi(2S)) / \sigma(J/\psi)$ was measured as a function of $W$ and compared to predictions of the perturbative QCD.

Primary author

Aleksander Zarnecki (University of Warsaw (PL))

Presentation materials