Transverse momentum spectra of cumulative particles and the quark coherent coalescence

• Vladimir Vechernin (St. Petersburg State University)

The transverse momentum dependence of the yields of particles produced from the clusters of dense cold nuclear matter in nuclei is calculated in the approach based on perturbative QCD calculations of the corresponding quark diagrams near the thresholds. It is shown that the transverse momentum dependence of the pion and proton spectra at different values of the Feynman variable x in the cumulative region, x > 1, can be described by the only parameter - the constituent quark mass, taken to be equal 300 MeV. It is found that the cumulative protons are formed predominantly via a coherent coalescence of three fast cluster quarks, whereas the production of cumulative pions is dominated by one fast cluster quark hadronization. This enabled to explain the experimentally observed more slow increase of the mean transverse momentum of cumulative protons with the cumulative variable x, compared to pions. The talk is based on the following papers: 1. M.A. Braun, V.V. Vechernin, Nucl. Phys. B 427, 614 (1994). 2. M.A. Braun, V.V. Vechernin, Physics of Atomic Nuclei 60, 432 (1997). 4. M.A. Braun, V.V. Vechernin, Physics of Atomic Nuclei 63, 1831 (2000). 5. M.A. Braun, V.V. Vechernin, Sov. J. Nucl. Phys. 36 (1982) 357. 6. M.A. Braun, V.V. Vechernin, J. Phys. G 16 (1990) 1615. 7. M. A. Braun, V.V. Vechernin, Theor. and Math. Phys. 139, 766 (2004). 8. V. Vechernin, AIP Conference Proceedings 1701, 060020 (2016).