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Title: Forming molecular states with hadronic rescattering

A method for modelling the prompt production of molecular states using the hadronic rescattering framework of the general-purpose Pythia event generator is introduced. Production cross sections of possible exotic hadronic molecules via hadronic rescattering at the LHC are calculated for the$$\chi _{c1}(3872)$$χc1(3872)resonance, a possible tetraquark state, as well as three possible pentaquark states,$$P_c^+(4312)$$Pc+(4312),$$P_c^+(4440)$$Pc+(4440), and$$P_c^+(4457)$$Pc+(4457). For the$$P_c^+$$Pc+states, the expected cross section from$$\Lambda _b$$Λbdecays is compared to the hadronic-rescattering production. The$$\chi _{c1}(3872)$$χc1(3872)cross section is compared to the fiducial$$\chi _{c1}(3872)$$χc1(3872)cross-section measurement by LHCb and found to contribute at a level of$${\mathcal {O}({1\%})}$$O(1%). Finally, the expected yields of$$\mathrm {P_c^{+}}$$Pc+production from hadronic rescattering during Run 3 of LHCb are estimated. The prompt background is found to be significantly larger than the prompt$$\mathrm {P_c^{+}}$$Pc+signal from hadronic rescattering.

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The European Physical Journal A
Springer Science + Business Media
Sponsoring Org:
National Science Foundation
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