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

TL;DR

This paper explores the potential of using the exclusive $pp o pp \, \phi \phi$ process to identify odderon exchange, which has no unambiguous experimental evidence but could explain certain discrepancies in proton-proton scattering data.

Contribution

It introduces a detailed theoretical framework for the central exclusive production of $\phi \phi$ pairs considering odderon exchange, and compares model predictions with experimental data to assess odderon's role.

Findings

Odderon exchange is not excluded by existing data.

Large $M_{\phi \phi}$ events at LHC could indicate odderon presence.

Model parameters are constrained by WA102 data.

Abstract

We discuss the possibility to use the $pp \to pp \phi \phi$ 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 $\phi \phi$ pairs in proton-proton collisions. We consider the pomeron-pomeron fusion to $\phi \phi$ ($\mathbb{P}\mathbb{P} \to \phi \phi$) through the continuum processes, due to the $\hat{t}$- and $\hat{u}$-channel reggeized $\phi$-meson, photon, and odderon exchanges, as well as through the $s$-channel resonance process ($\mathbb{P}\mathbb{P} \to f_{2}(2340) \to \phi \phi$). 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 $\phi \phi$ invariant masses. The measurement of large $M_{\phi \phi}$ or $\rm{Y_{diff}}$ events at the LHC would therefore suggest presence of the odderon exchange.