Structure and production mechanism of the enigmatic X (3872) in high-energy hadronic reactions

We calculate the total cross section and transverse momentum distributions for the production of the enigmatic chi(c1) (3872) (or X(3872)) assuming different scenarios: c (c) over bar state and D-0*D-0+D-0(D) over bar (0)* molecule. The derivative of the c (c) over bar wave function needed in the first scenario is taken from a potential model calculations. Compared to earlier calculations of molecular state we include not only single parton scattering (SPS) but also double parton scattering (DPS) contributions. The latter one seems to give smaller contribution than the SPS one. The upper limit for the DPS production of chi(c1) (3872) is much below the CMS data. We compare results of our calculations with existing experimental data of CMS, ATLAS and LHCb collaborations. Reasonable cross sections can be obtained in either c (c) over bar or molecular D (D) over bar* scenarios for X(3872), provided one takes into account both directly produced D-0, (D) over bar (0), as well as D-0, (D) over bar (0) from the decay of D*. However arguments related to the lifetime of D* suggest that the latter component is not active.

Automated summary

In this study, we investigate different scenarios for the production of the enigmatic chi(c1) (3872) particle and calculate its total cross section and momentum distribution. The results show that reasonable cross sections can be obtained in either the c (c) over bar state or the molecular D-0*D-0+D-0(D) over bar (0)* scenario, provided that both directly produced D-0, (D) over bar (0) and D-0, (D) over bar (0) from the decay of D* are taken into account.