2018/11/13 by Laura Tolós, Tolos, Laura, R. Pavao +3
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Nuclear Theory (nucl-th) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.1811.05149
openalex publication_date 2018/11/13 · openalex created_date 2018/11/29 · openalex updated_date 2026/07/28
We study the C=1, S=-2, I=0 sector, where five excited Ωc states have been recently observed by the LHCb Collaboration. We start from a recently developed unitarized baryon-meson model that takes, as bare baryon-meson interaction, an extended Weinberg-Tomozawa kernel consistent with both chiral and heavy-quark spin symmetries. This \rm SU(6) × \rm HQSS scheme leads to a successful description of the observed lowest-lying odd parity charmed Λc(2595) and Λc(2625) states, and bottomed Λb(5912) and Λb(5920) resonances. Within this model, five odd-parity Ωc states are dynamically generated, but with masses below 3 GeV, not allowing for an identification with the observed LHCb resonances. We revise this model and explore two different scenarios for the renormalization scheme, that is, using a modified common energy scale to perform the subtractions or utilizing a common ultraviolet cutoff to render finite the ultraviolet divergent loop functions in all channels. In both cases, we show that some (at least three) of the dynamically generated states can be identified with the experimental Ωc, while having odd parity and J=1/2 or J=3/2. Two of these states turn out to be part of the same \rm SU(6) × \rm HQSS multiplets as the charmed and bottomed Λ baryons.