Nuclear dependence of light neutral meson production in p-A collisions at 400 GeV with NA60

Autor: Arnaldi, R., Banicz, K., Borer, K., Castor, J., Chaurand, B., Chen, W., Cicalò, C., Colla, A., Cortese, P., Damjanovic, S., David, A., De Falco, A., Devaux, A., Ducroux, L., En'yo, H., Fargeix, J., Ferretti, A., Floris, M., Förster, A., Force, P., Guettet, N., Guichard, A., Gulkanian, H., Heuser, J. M., Jarron, P., Keil, M., Kluberg, L., Li, Z., Lourenço, C., Lozano, J., Manso, F., Martins, P., Masoni, A., Neves, A., Ohnishi, H., Oppedisano, C., Parracho, P., Pillot, P., Poghosyan, T., Puddu, G., Radermacher, E., Ramalhete, P., Rosinsky, P., Scomparin, E., Seixas, J., Serci, S., Shahoyan, R., Sonderegger, P., Specht, H. J., Tieulent, R., Uras, A., Usai, G., Veenhof, R., Wöhri, H. K.
Rok vydání: 2020
Předmět:
Zdroj: Eur.Phys.J.C 79 (2019) 5, 443
Druh dokumentu: Working Paper
DOI: 10.1140/epjc/s10052-019-6848-7
Popis: The NA60 experiment has studied low-mass muon pair production in proton-nucleus collisions with a system of Be, Cu, In, W, Pb and U targets, using a 400 GeV proton beam at the CERN SPS. The transverse momentum spectra of the $\rho/\omega$ and $\phi$ mesons are measured in the full $p_\mathrm{T}$ range accessible, from $p_\mathrm{T} = 0$ up to 2 GeV/$c$. The nuclear dependence of the production cross sections of the $\eta$, $\omega$ and $\phi$ mesons has been found to be consistent with the power law $\sigma_\mathrm{pA} \propto \mathrm{A}^\alpha$, with the $\alpha$ parameter increasing as a function of $p_\mathrm{T}$ for all the particles, and an approximate hierarchy $\alpha_\eta \approx \alpha_\phi > \alpha_\omega$. The cross section ratios $\sigma_\eta/\sigma_\omega$, $\sigma_\rho/\sigma_\omega$ and $\sigma_\phi/\sigma_\omega$ have been studied as a function of the size A of the production target, and an increase of the $\eta$ and $\phi$ yields relative to the $\omega$ is observed from p-Be to p-U collisions.
Databáze: arXiv