Hadronic three-body D decays mediated by scalar resonances
Journal
PHYSICAL REVIEW D
Journal Volume
105
Journal Issue
3
Date Issued
2022-01-03
Author(s)
Abstract
We study the quasi-two-body $D\to SP$ decays and the three-body $D$ decays
proceeding through intermediate scalar resonances, where $S$ and $P$ denote
scalar and pseudoscalar mesons, respectively. Our main results are: (i) Certain
external and internal $W$-emission diagrams with the emitted meson being a
scalar meson are na{\"i}vely expected to vanish, but they actually receive
contributions from vertex and hard spectator-scattering corrections beyond the
factorization approximation. (ii) For light scalars with masses below or close
to 1~GeV, it is more sensible to study three-body decays directly and compare
with experiment as the two-body branching fractions are either unavailable or
subject to large finite-width effects of the scalar meson. (iii) We consider
the two-quark (scheme I) and four-quark (scheme II) descriptions of the light
scalar mesons, and find the latter generally in better agreement with
experiment. This is in line with recent BESIII measurements of semileptonic
charm decays that prefer the tetraquark description of light scalars produced
in charmed meson decays. (iv) The topological amplitude approach fails here as
the $D\to SP$ decay branching fractions cannot be reliably inferred from the
measurements of three-body decays, mainly because the decay rates cannot be
factorized into the topological amplitude squared and the phase space factor.
(v) The predicted rates for $D^0\to f_0 P, a_0 P$ are generally smaller than
experimental data by one order of magnitude, presumably implying the
significance of $W$-exchange amplitudes. (vi) The $W$-annihilation amplitude is
found to be very sizable in the $SP$ sector with $|A/T|_{SP}\sim 1/2$, contrary
to its suppression in the $PP$ sector with $|A/T|_{PP}\sim 0.18$.
Subjects
QCD FACTORIZATION; MULTIQUARK HADRONS; NONLEPTONIC DECAYS; RADIATIVE DECAYS; MESONS; HEAVY; STATE; PHI; High Energy Physics - Phenomenology; High Energy Physics - Phenomenology; High Energy Physics - Experiment; High Energy Physics - Lattice
Publisher
AMER PHYSICAL SOC
Description
30 pages, 2 figures, references and discussions added, version
accepted by PRD
accepted by PRD
Type
journal article