60 research outputs found
On the possibility of testing the two-peak structure of the LHCb hidden-charm strange pentaquark in near-threshold antikaon-induced charmonium production on protons and nuclei
Accounting for the LHCb observation that the reported hidden-charm strange
pentaquark can split into two substructures,
and , with a mass difference of 13 MeV as well as the newly
observed hidden-charm pentaquark resonance with strangeness,
we study within the double-peak scenario for the state the
near-threshold meson production from protons and nuclei by considering
incoherent direct non-resonant () and two-step
resonant (, , 2, 3;
, ,
) charmonium production processes with the main
goal of clarifying the possibility to observe within this scenario both above
two substructures contributing to the state and the
resonance in this production. We calculate the absolute
excitation functions, energy and momentum distributions for the non-resonant,
resonant and for the combined (non-resonant plus resonant) production of
mesons on protons as well as on carbon and tungsten target nuclei at
near-threshold incident antikaon beam momenta by assuming the spin-parity
assignments of the hidden-charm resonances ,
and as , and within
four different realistic choices for the branching ratios of their decays to
the mode (0.125, 0.25, 0.5 and 1\%) as well as for two
options for the branching fraction of their decays to the channel (0.01
and 0.001\%). We show that these combined observables reveal clear sensitivity
to these scenarios. Hence, they may be an important tool to provide further
evidence for the existence of the above strange hidden-charm pentaquark
resonances.Comment: 28 pages, 13 figures. arXiv admin note: text overlap with
arXiv:2211.1603
Subthreshold Production on Nuclei by Mesons
The inclusive mesons production in --nucleus reactions in the
subthreshold energy regime is analyzed with respect to the one--step
() and the two--step () incoherent production processes on the basis of an appropriate
folding model, which allows one to take into account the various forms of an
internal nucleon momentum distribution as well as on-- and off--shell
propagation of the struck target nucleon. Contrary to proton--nucleus reactions
primary reaction channel is found to be significant practically at all
considered energies. Detailed predictions for the total and invariant
differential cross sections from \piC-- and \piPb--collisions at subthreshold
energies are provided.Comment: 18 pages, LaTeX, uses ws-art.sty, gzip+uuencoded postscript. Figures
are available by request from [email protected]
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