We study the dependence on the quark mass of the compositeness of the lowest-lying odd parity hyperon states. Thus, we pay attention to Lambda-like states in the strange, charm, and beauty sectors which are dynamically generated using a unitarized meson-baryon model. In the strange sector we use a SU(6) extension of the Weinberg-Tomozawa meson-baryon interaction, and we further implement the heavy-quark spin symmetry to construct the meson-baryon interaction when charmed or beauty hadrons are involved. In the three examined flavor sectors, we obtain two J(P) = 1/2- and one J(P) = 3/2(-) Lambda states. We find that the. states which are bound states (the three Lambda(b)) or narrow resonances [one Lambda(1405) and one Lambda(c)(2595)] are well described as molecular states composed of s-wave meson-baryon pairs. The 1/2(-) wide Lambda(1405) and Lambda(c)(2595) as well as the 3/2(-) Lambda(1520) and Lambda(c)(2625) states display smaller compositeness so they would require new mechanisms, such as d-wave interactions.

We thank E. Oset for careful proofreading and comments. C. H.-D. thanks the support of the JAE-CSIC Program. This research was supported by Spanish Ministerio de Economia y Competitividad and European FEDER funds under Contracts No. FPA2010-16963, No. FIS2011-28853-C02-02, No. FPA2013-43425-P, No. FIS2014-59386-P, No. FIS2014-51948-C2-1-P and No. FIS2014-57026-REDT, and by Junta de Andalucia, Grant No. FQM-225. L. T. acknowledges support from the Ramon y Cajal Research Programme from Ministerio de Ciencia e Innovacion and from FP7-PEOPLE-2011-CIG under Contract No. PCIG09-GA-2011-291679.

14 pages.- 2 figures.- 5 tables

Peer reviewed