What are the right values of Λ and the heavy quark kinetic energy?

The values of two important parameters of the heavy quark effective theory, Λ and μπ2 (the mean value of the heavy quark three momentum squared), have been determined recently by Gremm et al. [M. Gremm, A. Kapustin, Z. Ligeti, M. Wise, CALT-68-2043, hep-ph/9603314 (original and revised versions)] from the precise CLEO data on the shape of the electron spectrum in semileptonic B meson decays. The values obtained by Gremm et al.: Λ = (0.55 ± 0.05) GeV, μπ2 = (0.35 ± 0.05) GeV2, disagree with the result obtained earlier by Chernyak [Nucl. Phys. B 457 (1995) 961] from the D meson semileptonic width. The purpose of this note is to show that the main reason for a disagreement is the secondary electron background present in the data, which influences strongly the extracted values of Λ and μπ2. We determine the amount of this background from the selfconsistency conditions, and subtract it out. As a result, the values of Λ and μπ2 become a factor two smaller and agree with Chernyak (q.v.).