4 research outputs found
SU(3) Corrections to B -> D l nu Form Factors at O(1/M)
We compute the O(1/M,m_s) heavy quark and SU(3) corrections to B_s -> D_s e
nu form factors. In the limit of vanishing light quark mass, B_s -> D_s e nu
form factors are given in terms of the the B -> D e nu form factors, the
leading order chiral parameter g, and two O(1/M) chiral parameters and
. All the chiral parameters can be extracted, in principle, from other
heavy meson decays. Analytic counterterms proportional to the strange quark
mass are presented for completeness, but no predictive power remains when they
are included. Anomalously large loop corrections warn of poor convergence of
the heavy quark chiral symmetry expansion for these processes. This suggests
that naive extrapolations of B \to D form factors relying on heavy quark and
chiral symmetries, as often used in monte carlo simulations of lattice QCD, may
incur large errors.Comment: uuencoded, 24 pages, 6 eps figures, uses lanlmac/harvmac (suggest `b'
size) and epsf.tex (if you want auto-insertion of figs)
Chiral and Heavy Quark Symmetry Violation in B Decays
The most general Lagrangian consistent with chiral, heavy quark, and strong
interaction symmetries to order and to linear order in the SU(3) vector
and axial currents is presented. Two new dimensionful and five dimensionless
couplings arise at this order. The heavy to light flavor changing current is
derived to the same order, giving rise to two additional dimensionful constants
and six dimensionless ones. The dimensionless parameters are shown to be
irrelevant at \ord. The leading nonanalytic heavy quark and chiral symmetry
violating corrections to heavy meson decay constants are computed, and
implications to B decays are discussed; measurements of the experimentally
accessible form factors for and , along with
knowledge of the coupling, determine the eight decay constants
, , , , , , , and
, as well as one relation among the form factors,
to \ord~. The ratio is
expressed in terms of two dimensionful couplings.Comment: 22 pages, harvmac, 5 eps figs, resubmitted for automated postscrip
Radiative Decay Using Heavy Quark and Chiral Symmetry
The implications of chiral symmetry and heavy quark
symmetry for the radiative decays , ,
and are discussed. Particular attention is paid to
violating contributions of order . Experimental data on these
radiative decays provide constraints on the coupling.Comment: 9 pages plus 3 pages of figures in POSTSCRIPT file appended to TeX
file (uses harvmac.tex and tables.tex), UCSD/PTH 92-31, CALT-68-1816,
EFI-92-45, CERN-TH.6650/9