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Excited scalar and pseudoscalar mesons in the extended linear sigma model.

ABSTRACT: We present an in-depth study of masses and decays of excited scalar and pseudoscalar [Formula: see text] states in the Extended Linear Sigma Model (eLSM). The model also contains ground-state scalar, pseudoscalar, vector and axial-vector mesons. The main objective is to study the consequences of the hypothesis that the [Formula: see text] resonance, observed a decade ago by the BES Collaboration and recently by LHCb, represents an excited scalar quarkonium. In addition we also analyse the possibility that the new [Formula: see text] resonance, observed recently by BABAR, may also be an excited scalar state. Both hypotheses receive justification in our approach although there appears to be some tension between the simultaneous interpretation of [Formula: see text]/[Formula: see text] and pseudoscalar mesons [Formula: see text], [Formula: see text], [Formula: see text] and K(1460) as excited [Formula: see text] states.

SUBMITTER: Parganlija D

PROVIDER: S-EPMC5512613 | biostudies-other | 2017

REPOSITORIES: biostudies-other

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