TY  - JOUR
AU  - Nieves, J.
AU  - Pavao, R.
AU  - Sakai, S.
PY  - 2019
DA  - 2019//
TI  - Lambda(b) decays into Lambda cl(nu)over-barl and Lambda c*pi(-) [ Lambda(c)* = Lambda(c)( 2595) and Lambda(c)(2625)] and heavy quark spin symmetry
T2  - Eur. Phys. J. C
JO  - European Physical Journal C
SP  - 417 - 20pp
VL  - 79
IS  - 5
PB  - Springer
AB  - We study the implications for bc=c(2595) and c(2625)] decays that can be deduced from heavy quark spin symmetry (HQSS). Identifying the odd parity c(2595) and c(2625) resonances as HQSS partners, with total angular momentum-parity jqP=1- for the light degrees of freedom, we find that the ratios (bc(2595)-)/(bc(2625)-) and (bc(2595)) agree, within errors, with the experimental values given in the Review of Particle Physics. We discuss how future, and more precise, measurements of the above branching fractions could be used to shed light into the inner HQSS structure of the narrow c(2595) odd-parity resonance. Namely, we show that such studies would constrain the existence of a sizable jqP</mml:msubsup>=0- component in its wave-function, and/or of a two-pole pattern, in analogy to the case of the similar (1405) resonance in the strange sector, as suggested by most of the approaches that describe the c(2595) as a hadron molecule. We also investigate the lepton flavor universality ratios R[c]=B( may be affected by a new source of potentially large systematic errors if there are two) poles.
SN  - 1434-6044
UR  - https://arxiv.org/abs/1903.11911
UR  - https://doi.org/10.1140/epjc/s10052-019-6929-7
DO  - 10.1140/epjc/s10052-019-6929-7
LA  - English
N1  - WOS:000468374700002
ID  - Nieves_etal2019
ER  -