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D Mesons in Nuclear Matter: A DN Coupled-Channel Equations Approach

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 نشر من قبل Angels Ramos
 تاريخ النشر 2006
  مجال البحث
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A set of coupled two-body scattering equations is solved for the DN system embedded in an iso-symmetric nuclear matter. The in-medium behavior of charmed D mesons: (D^+,D^0), is investigated from the self-consistent solution within this scheme. The effective meson-baryon Lagrangian in charm quantum number one sector, the key ingredient in the present study, is adopted from a recent model by Hofmann and Lutz which has aimed at combining the charmed meson degree of freedom in a consistent manner with chiral unitary models. After a critical examination, the original model is modified in several important aspects, such as the method of regularization, in order to be more consistent and practical for our objective. The resultant interaction is used to reproduce the position and width of the s-wave Lambda_c(2593) resonance in the isospin zero DN channel. In the isospin one channel, it generates a rather wide resonance at ~2770 MeV. The corresponding in-medium solution is then sought by incorporating Pauli blocking and the D- and pi-meson dressing self-consistently. At normal nuclear matter density, the resultant Lambda_c (2593) is found to stay narrow and shifted at a lower energy, while the I=1 resonance is lowered in position as well and broadened considerably. The possible implication of our findings on the J/Psi suppression, etc. in relativistic heavy ion collisions is briefly discussed.

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