THE ISGUR-WISE FUNCTION TO O(αs) FROM SUM RULES IN THE HEAVY QUARK EFFECTIVE THEORY
نویسندگان
چکیده
Radiative corrections to both perturbative and non-perturbative contributions are added to existing calculations of the Isgur-Wise function ξIW . To this end, we develop a method for calculating two-loop integrals in the heavy quark effective theory involving two different scales. The inclusion of O(αs) terms causes ξIW to decrease as compared to the lowest order result and shows the importance of quantum effects. The slope parameter ρ violates the bound given by de Rafael and Taron. Submitted to Phys. Lett. B. A. v. Humboldt fellow. On leave of absence from Grup de F́ısica Teòrica, Departament de F́ısica, Universitat Autònoma de Barcelona, E-08193 Bellaterra (Barcelona), Spain, until 30th. Sep. 92 † Adress after September 1992: Physik Department, TU München, D-8046 Garching bei München, FRG
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