Subleading Isgur-Wise form factor τ(v⋅v′) at O(1/mQ) for Λb→Λc11/2,3/2 weak transition is calculated by using the QCD sum rules in the framework of the heavy quark effective theory (HQET), where Λc11/2 and Λc13/2 are the orbitally excited charmed baryon doublet with JP=(1−/2,3−/2). We consider the subleading contributions from the weak current matching in the HQET. The interpolating currents with transverse covariant derivative are adopted for Λc11/2 and Λc13/2 in the analysis. The slope parameter ρ2 in linear approximation of τ is obtained to be ρ2=2.76 and the interception to be τ(1)=−1.27 GeV.
@article{arxiv.hep-ph/0210097,
title = {Subleading Isgur-Wise Function of $\Lambda_b\to\Lambda_{c1}$ using QCD sum rules},
author = {Jong-Phil Lee and Gye T. Park},
journal= {arXiv preprint arXiv:hep-ph/0210097},
year = {2009}
}