Measurement of the cross-section ratio $\sigma_{\psi(2S )}/\sigma_{J/\psi(1S )}$ in exclusive photoproduction at HERA
| Autor: | ZEUS Collaboration, Abt, I., Adamus, M., Aggarwal, R., Aushev, V., Behnke, O., Bertolin, A., Bloch, I., Brock, I., Brook, N. H., Brugnera, R., Bruni, A., Bussey, P. J., Caldwell, A., Catterall, C. D., Chwastowski, J., Ciborowski, J., Ciesielski, R., Cooper-Sarkar, A. M., Corradi, M., Dementiev, R. K., Dusini, S., Ferrando, J., Foster, B., Gallo, E., Gangadharan, D., Garfagnini, A., Geiser, A., Grzelak, G., Gwenlan, C., Hochman, D., Jomhari, N. Z., Kadenko, I., Karshon, U., Kaur, P., Klanner, R., Klein, U., Korzhavina, I. A., Kovalchuk, N., Kuze, M., Levchenko, B. B., Levy, A., Löhr, B., Lohrmann, E., Longhin, A., Lorkowski, F., Makarenko, I., Malka, J., Masciocchi, S., Nagano, K., Nam, J. D., Onishchuk, Yu., Paul, E., Pidhurskyi, I., Polini, A., Przybycień, M., Quintero, A., Rubinsky, I., Ruspa, M., Schneekloth, U., Schörner-Sadenius, T., Selyuzhenkov, I., Shchedrolosiev, M., Shcheglova, L. M., Skillicorn, I. O., Słomiński, W., Solano, A., Stanco, L., Stefaniuk, N., Surrow, B., Tokushuku, K., Tomaszewska, J., Trofymov, A., Turkot, O., Tymieniecka, T., Verbytskyi, A., Abdullah, W. A. T. Wan, Wichmann, K., Wing, M., Yamada, S., Yamazaki, Y., Żarnecki, A. F., Zenaiev, O. |
|---|---|
| Rok vydání: | 2022 |
| Předmět: | |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1007/JHEP12(2022)164 |
| Popis: | The exclusive photoproduction reactions $\gamma p \to J/\psi(1S) p$ and $\gamma p \to \psi(2S) p$ have been measured at an $ep$ centre-of-mass energy of 318 GeV with the ZEUS detector at HERA using an integrated luminosity of 373 pb$^{-1}$. The measurement was made in the kinematic range $30 < W < 180$ GeV, $Q^2 < 1$ GeV$^2$ and $|t| < 1$ GeV$^2$, where $W$ is the photon--proton centre-of-mass energy, $Q^2$ is the photon virtuality and $t$ is the squared four-momentum transfer at the proton vertex. The decay channels used were $J/\psi(1S) \to \mu^+ \mu^-$, $\psi(2S) \to \mu^+ \mu^-$ and $\psi(2S) \to J/\psi(1S) \pi^+ \pi^-$ with subsequent decay $J/\psi(1S) \to \mu^+ \mu^-$. The ratio of the production cross sections, $R = \sigma_{\psi(2S)} / \sigma_{J/\psi(1S)}$, has been measured as a function of $W$ and $|t|$ and compared to previous data in photoproduction and deep inelastic scattering and with predictions of QCD-inspired models of exclusive vector-meson production, which are in reasonable agreement with the data. Comment: 31 pages, 9 figures. Updated according to comments from journal referee including a new table. Added full collaboration author list |
| Databáze: | arXiv |
| Externí odkaz: |
|