Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
1999-06-29
Int.J.Mod.Phys. A15 (2000) 1817-1857
Physics
High Energy Physics
High Energy Physics - Phenomenology
28 pages, Revtex, 5 figures, 3 tables, minor changes with "dressed heavy quark" being addressed, to be published in Int. J. Mo
Scientific paper
10.1142/S0217751X00000793
The heavy quark effective field theory (HQEFT) containing both effective `quark fields' and `antiquark fields' is investigated in detail. By integrating out (but not neglecting) the effective antiquark fields, we present a new formulation of effective theory which differs from the usual heavy quark effective theory (HQET) and exhibits valuable features because of the inclusion of the contributions from the antiquark fields. Matrix elements of vector and axial vector heavy quark currents between pseudoscalar and vector mesons containing a heavy quark (b or c) are then evaluated systematically up to the order of $1/m^2_Q$ and parameterized by a set of universal form factors. With a consistent normalization condition between the effective heavy hadron states, the form factors at zero recoil are related to the ground state meson masses, which enables us to estimate the values of form factors at zero recoil. In particular, the Luke's theorem comes out automatically in the new formulation of HQEFT without the need of imposing the equation of motion $iv\cdot D Q^{+}_{v} =0$. Consequently, the differential decay rates of both $B\to D^{\ast}l\nu$ and $B\to D l\nu$ do not receive $1/m_{Q}$ order corrections at zero recoil, which is not the case in the usual HQET. Thus we quote that the Cabibbo-Kobayashi-Maskawa matrix element $| V_{cb}|$ can nicely be extracted from either of these two exclusive semileptonic decays at the order of $1/m^2_Q$. Our estimates for $|V_{cb}|$ are presented.
Wang Wan-Ying
Wu Yue-Liang
Yan Y. A.
No associations
LandOfFree
Weak Matrix Elements and |V_cb| in New Formulation of Heavy Quark Effective Field Theory does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Weak Matrix Elements and |V_cb| in New Formulation of Heavy Quark Effective Field Theory, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Weak Matrix Elements and |V_cb| in New Formulation of Heavy Quark Effective Field Theory will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-422257