Searching for odderon exchange in exclusive $pp\to pp\varphi \varphi$ reaction

Abstract

We discuss the possibility to use the $pp\to pp\varphi \varphi$ process in identifying the odderon exchange. So far there is no unambiguous experimental evidence for the odderon, the charge conjugation $C=-1$ counterpart of the $C=+1$ pomeron. Last year results of the TOTEM collaboration suggest that the odderon exchange can be responsible for a disagreement of theoretical calculations and the TOTEM data for elastic proton-proton scattering. Here we present recent studies for central exclusive production (CEP) of $\varphi \varphi$ pairs in proton-proton collisions. We consider the pomeron-pomeron fusion to $\varphi \varphi$ ($\mathbb{PP}\to \varphi \varphi$) through the continuum processes, due to the $\hat{t}$- and $\hat{u}$-channel reggeized $\varphi$-meson, photon, and odderon exchanges, as well as through the $s$-channel resonance process ($\mathbb{PP}\to f_2(2340)\to \varphi \varphi$). This $f_2$ state is a candidate for a tensor glueball. The amplitudes for the processes are formulated within the tensor-pomeron and vector-odderon approach. Some model parameters are determined from the comparison to the WA102 experimental data. The odderon exchange is not excluded by the WA102 data for high $\varphi \varphi$ invariant masses. The measurement of large $M_{\varphi \varphi }$ or ${\mathrm{Y}}_{\mathrm{diff}}$ events at the LHC would therefore suggest presence of the odderon exchange.

Comments: 6 pages, 2 figures, to appear in Proceedings of European Physical Society Conference on High Energy Physics - EPS-HEP2019, Ghent, Belgium, 10-17 July, 2019